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4349 | Serge | 1 | |
2 | * |
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3 | * libpng version 1.6.5 - September 14, 2013 |
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4 | * Copyright (c) 1998-2013 Glenn Randers-Pehrson |
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5 | * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) |
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6 | * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) |
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7 | * |
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8 | * This code is released under the libpng license (See LICENSE, below) |
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9 | * |
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10 | * Authors and maintainers: |
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11 | * libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat |
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12 | * libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger |
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13 | * libpng versions 0.97, January 1998, through 1.6.5 - September 14, 2013: Glenn |
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14 | * See also "Contributing Authors", below. |
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15 | * |
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16 | * Note about libpng version numbers: |
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17 | * |
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18 | * Due to various miscommunications, unforeseen code incompatibilities |
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19 | * and occasional factors outside the authors' control, version numbering |
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20 | * on the library has not always been consistent and straightforward. |
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21 | * The following table summarizes matters since version 0.89c, which was |
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22 | * the first widely used release: |
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23 | * |
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24 | * source png.h png.h shared-lib |
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25 | * version string int version |
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26 | * ------- ------ ----- ---------- |
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27 | * 0.89c "1.0 beta 3" 0.89 89 1.0.89 |
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28 | * 0.90 "1.0 beta 4" 0.90 90 0.90 [should have been 2.0.90] |
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29 | * 0.95 "1.0 beta 5" 0.95 95 0.95 [should have been 2.0.95] |
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30 | * 0.96 "1.0 beta 6" 0.96 96 0.96 [should have been 2.0.96] |
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31 | * 0.97b "1.00.97 beta 7" 1.00.97 97 1.0.1 [should have been 2.0.97] |
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32 | * 0.97c 0.97 97 2.0.97 |
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33 | * 0.98 0.98 98 2.0.98 |
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34 | * 0.99 0.99 98 2.0.99 |
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35 | * 0.99a-m 0.99 99 2.0.99 |
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36 | * 1.00 1.00 100 2.1.0 [100 should be 10000] |
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37 | * 1.0.0 (from here on, the 100 2.1.0 [100 should be 10000] |
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38 | * 1.0.1 png.h string is 10001 2.1.0 |
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39 | * 1.0.1a-e identical to the 10002 from here on, the shared library |
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40 | * 1.0.2 source version) 10002 is 2.V where V is the source code |
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41 | * 1.0.2a-b 10003 version, except as noted. |
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42 | * 1.0.3 10003 |
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43 | * 1.0.3a-d 10004 |
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44 | * 1.0.4 10004 |
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45 | * 1.0.4a-f 10005 |
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46 | * 1.0.5 (+ 2 patches) 10005 |
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47 | * 1.0.5a-d 10006 |
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48 | * 1.0.5e-r 10100 (not source compatible) |
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49 | * 1.0.5s-v 10006 (not binary compatible) |
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50 | * 1.0.6 (+ 3 patches) 10006 (still binary incompatible) |
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51 | * 1.0.6d-f 10007 (still binary incompatible) |
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52 | * 1.0.6g 10007 |
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53 | * 1.0.6h 10007 10.6h (testing xy.z so-numbering) |
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54 | * 1.0.6i 10007 10.6i |
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55 | * 1.0.6j 10007 2.1.0.6j (incompatible with 1.0.0) |
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56 | * 1.0.7beta11-14 DLLNUM 10007 2.1.0.7beta11-14 (binary compatible) |
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57 | * 1.0.7beta15-18 1 10007 2.1.0.7beta15-18 (binary compatible) |
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58 | * 1.0.7rc1-2 1 10007 2.1.0.7rc1-2 (binary compatible) |
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59 | * 1.0.7 1 10007 (still compatible) |
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60 | * 1.0.8beta1-4 1 10008 2.1.0.8beta1-4 |
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61 | * 1.0.8rc1 1 10008 2.1.0.8rc1 |
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62 | * 1.0.8 1 10008 2.1.0.8 |
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63 | * 1.0.9beta1-6 1 10009 2.1.0.9beta1-6 |
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64 | * 1.0.9rc1 1 10009 2.1.0.9rc1 |
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65 | * 1.0.9beta7-10 1 10009 2.1.0.9beta7-10 |
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66 | * 1.0.9rc2 1 10009 2.1.0.9rc2 |
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67 | * 1.0.9 1 10009 2.1.0.9 |
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68 | * 1.0.10beta1 1 10010 2.1.0.10beta1 |
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69 | * 1.0.10rc1 1 10010 2.1.0.10rc1 |
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70 | * 1.0.10 1 10010 2.1.0.10 |
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71 | * 1.0.11beta1-3 1 10011 2.1.0.11beta1-3 |
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72 | * 1.0.11rc1 1 10011 2.1.0.11rc1 |
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73 | * 1.0.11 1 10011 2.1.0.11 |
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74 | * 1.0.12beta1-2 2 10012 2.1.0.12beta1-2 |
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75 | * 1.0.12rc1 2 10012 2.1.0.12rc1 |
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76 | * 1.0.12 2 10012 2.1.0.12 |
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77 | * 1.1.0a-f - 10100 2.1.1.0a-f (branch abandoned) |
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78 | * 1.2.0beta1-2 2 10200 2.1.2.0beta1-2 |
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79 | * 1.2.0beta3-5 3 10200 3.1.2.0beta3-5 |
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80 | * 1.2.0rc1 3 10200 3.1.2.0rc1 |
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81 | * 1.2.0 3 10200 3.1.2.0 |
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82 | * 1.2.1beta1-4 3 10201 3.1.2.1beta1-4 |
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83 | * 1.2.1rc1-2 3 10201 3.1.2.1rc1-2 |
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84 | * 1.2.1 3 10201 3.1.2.1 |
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85 | * 1.2.2beta1-6 12 10202 12.so.0.1.2.2beta1-6 |
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86 | * 1.0.13beta1 10 10013 10.so.0.1.0.13beta1 |
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87 | * 1.0.13rc1 10 10013 10.so.0.1.0.13rc1 |
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88 | * 1.2.2rc1 12 10202 12.so.0.1.2.2rc1 |
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89 | * 1.0.13 10 10013 10.so.0.1.0.13 |
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90 | * 1.2.2 12 10202 12.so.0.1.2.2 |
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91 | * 1.2.3rc1-6 12 10203 12.so.0.1.2.3rc1-6 |
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92 | * 1.2.3 12 10203 12.so.0.1.2.3 |
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93 | * 1.2.4beta1-3 13 10204 12.so.0.1.2.4beta1-3 |
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94 | * 1.0.14rc1 13 10014 10.so.0.1.0.14rc1 |
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95 | * 1.2.4rc1 13 10204 12.so.0.1.2.4rc1 |
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96 | * 1.0.14 10 10014 10.so.0.1.0.14 |
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97 | * 1.2.4 13 10204 12.so.0.1.2.4 |
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98 | * 1.2.5beta1-2 13 10205 12.so.0.1.2.5beta1-2 |
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99 | * 1.0.15rc1-3 10 10015 10.so.0.1.0.15rc1-3 |
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100 | * 1.2.5rc1-3 13 10205 12.so.0.1.2.5rc1-3 |
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101 | * 1.0.15 10 10015 10.so.0.1.0.15 |
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102 | * 1.2.5 13 10205 12.so.0.1.2.5 |
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103 | * 1.2.6beta1-4 13 10206 12.so.0.1.2.6beta1-4 |
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104 | * 1.0.16 10 10016 10.so.0.1.0.16 |
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105 | * 1.2.6 13 10206 12.so.0.1.2.6 |
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106 | * 1.2.7beta1-2 13 10207 12.so.0.1.2.7beta1-2 |
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107 | * 1.0.17rc1 10 10017 12.so.0.1.0.17rc1 |
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108 | * 1.2.7rc1 13 10207 12.so.0.1.2.7rc1 |
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109 | * 1.0.17 10 10017 12.so.0.1.0.17 |
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110 | * 1.2.7 13 10207 12.so.0.1.2.7 |
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111 | * 1.2.8beta1-5 13 10208 12.so.0.1.2.8beta1-5 |
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112 | * 1.0.18rc1-5 10 10018 12.so.0.1.0.18rc1-5 |
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113 | * 1.2.8rc1-5 13 10208 12.so.0.1.2.8rc1-5 |
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114 | * 1.0.18 10 10018 12.so.0.1.0.18 |
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115 | * 1.2.8 13 10208 12.so.0.1.2.8 |
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116 | * 1.2.9beta1-3 13 10209 12.so.0.1.2.9beta1-3 |
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117 | * 1.2.9beta4-11 13 10209 12.so.0.9[.0] |
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118 | * 1.2.9rc1 13 10209 12.so.0.9[.0] |
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119 | * 1.2.9 13 10209 12.so.0.9[.0] |
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120 | * 1.2.10beta1-7 13 10210 12.so.0.10[.0] |
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121 | * 1.2.10rc1-2 13 10210 12.so.0.10[.0] |
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122 | * 1.2.10 13 10210 12.so.0.10[.0] |
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123 | * 1.4.0beta1-5 14 10400 14.so.0.0[.0] |
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124 | * 1.2.11beta1-4 13 10211 12.so.0.11[.0] |
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125 | * 1.4.0beta7-8 14 10400 14.so.0.0[.0] |
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126 | * 1.2.11 13 10211 12.so.0.11[.0] |
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127 | * 1.2.12 13 10212 12.so.0.12[.0] |
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128 | * 1.4.0beta9-14 14 10400 14.so.0.0[.0] |
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129 | * 1.2.13 13 10213 12.so.0.13[.0] |
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130 | * 1.4.0beta15-36 14 10400 14.so.0.0[.0] |
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131 | * 1.4.0beta37-87 14 10400 14.so.14.0[.0] |
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132 | * 1.4.0rc01 14 10400 14.so.14.0[.0] |
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133 | * 1.4.0beta88-109 14 10400 14.so.14.0[.0] |
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134 | * 1.4.0rc02-08 14 10400 14.so.14.0[.0] |
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135 | * 1.4.0 14 10400 14.so.14.0[.0] |
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136 | * 1.4.1beta01-03 14 10401 14.so.14.1[.0] |
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137 | * 1.4.1rc01 14 10401 14.so.14.1[.0] |
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138 | * 1.4.1beta04-12 14 10401 14.so.14.1[.0] |
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139 | * 1.4.1 14 10401 14.so.14.1[.0] |
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140 | * 1.4.2 14 10402 14.so.14.2[.0] |
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141 | * 1.4.3 14 10403 14.so.14.3[.0] |
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142 | * 1.4.4 14 10404 14.so.14.4[.0] |
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143 | * 1.5.0beta01-58 15 10500 15.so.15.0[.0] |
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144 | * 1.5.0rc01-07 15 10500 15.so.15.0[.0] |
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145 | * 1.5.0 15 10500 15.so.15.0[.0] |
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146 | * 1.5.1beta01-11 15 10501 15.so.15.1[.0] |
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147 | * 1.5.1rc01-02 15 10501 15.so.15.1[.0] |
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148 | * 1.5.1 15 10501 15.so.15.1[.0] |
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149 | * 1.5.2beta01-03 15 10502 15.so.15.2[.0] |
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150 | * 1.5.2rc01-03 15 10502 15.so.15.2[.0] |
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151 | * 1.5.2 15 10502 15.so.15.2[.0] |
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152 | * 1.5.3beta01-10 15 10503 15.so.15.3[.0] |
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153 | * 1.5.3rc01-02 15 10503 15.so.15.3[.0] |
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154 | * 1.5.3beta11 15 10503 15.so.15.3[.0] |
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155 | * 1.5.3 [omitted] |
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156 | * 1.5.4beta01-08 15 10504 15.so.15.4[.0] |
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157 | * 1.5.4rc01 15 10504 15.so.15.4[.0] |
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158 | * 1.5.4 15 10504 15.so.15.4[.0] |
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159 | * 1.5.5beta01-08 15 10505 15.so.15.5[.0] |
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160 | * 1.5.5rc01 15 10505 15.so.15.5[.0] |
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161 | * 1.5.5 15 10505 15.so.15.5[.0] |
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162 | * 1.5.6beta01-07 15 10506 15.so.15.6[.0] |
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163 | * 1.5.6rc01-03 15 10506 15.so.15.6[.0] |
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164 | * 1.5.6 15 10506 15.so.15.6[.0] |
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165 | * 1.5.7beta01-05 15 10507 15.so.15.7[.0] |
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166 | * 1.5.7rc01-03 15 10507 15.so.15.7[.0] |
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167 | * 1.5.7 15 10507 15.so.15.7[.0] |
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168 | * 1.6.0beta01-40 16 10600 16.so.16.0[.0] |
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169 | * 1.6.0rc01-08 16 10600 16.so.16.0[.0] |
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170 | * 1.6.0 16 10600 16.so.16.0[.0] |
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171 | * 1.6.1beta01-09 16 10601 16.so.16.1[.0] |
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172 | * 1.6.1rc01 16 10601 16.so.16.1[.0] |
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173 | * 1.6.1 16 10601 16.so.16.1[.0] |
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174 | * 1.6.2beta01 16 10602 16.so.16.2[.0] |
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175 | * 1.6.2rc01-06 16 10602 16.so.16.2[.0] |
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176 | * 1.6.2 16 10602 16.so.16.2[.0] |
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177 | * 1.6.3beta01-11 16 10603 16.so.16.3[.0] |
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178 | * 1.6.3rc01 16 10603 16.so.16.3[.0] |
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179 | * 1.6.3 16 10603 16.so.16.3[.0] |
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180 | * 1.6.4beta01-02 16 10604 16.so.16.4[.0] |
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181 | * 1.6.4rc01 16 10604 16.so.16.4[.0] |
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182 | * 1.6.4 16 10604 16.so.16.4[.0] |
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183 | * 1.6.5 16 10605 16.so.16.5[.0] |
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184 | * |
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185 | * Henceforth the source version will match the shared-library major |
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186 | * and minor numbers; the shared-library major version number will be |
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187 | * used for changes in backward compatibility, as it is intended. The |
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188 | * PNG_LIBPNG_VER macro, which is not used within libpng but is available |
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189 | * for applications, is an unsigned integer of the form xyyzz corresponding |
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190 | * to the source version x.y.z (leading zeros in y and z). Beta versions |
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191 | * were given the previous public release number plus a letter, until |
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192 | * version 1.0.6j; from then on they were given the upcoming public |
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193 | * release number plus "betaNN" or "rcNN". |
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194 | * |
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195 | * Binary incompatibility exists only when applications make direct access |
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196 | * to the info_ptr or png_ptr members through png.h, and the compiled |
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197 | * application is loaded with a different version of the library. |
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198 | * |
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199 | * DLLNUM will change each time there are forward or backward changes |
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200 | * in binary compatibility (e.g., when a new feature is added). |
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201 | * |
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202 | * See libpng-manual.txt or libpng.3 for more information. The PNG |
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203 | * specification is available as a W3C Recommendation and as an ISO |
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204 | * Specification, |
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205 | */ |
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206 | |||
207 | |||
208 | * COPYRIGHT NOTICE, DISCLAIMER, and LICENSE: |
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209 | * |
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210 | * If you modify libpng you may insert additional notices immediately following |
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211 | * this sentence. |
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212 | * |
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213 | * This code is released under the libpng license. |
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214 | * |
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215 | * libpng versions 1.2.6, August 15, 2004, through 1.6.5, September 14, 2013, are |
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216 | * Copyright (c) 2004, 2006-2013 Glenn Randers-Pehrson, and are |
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217 | * distributed according to the same disclaimer and license as libpng-1.2.5 |
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218 | * with the following individual added to the list of Contributing Authors: |
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219 | * |
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220 | * Cosmin Truta |
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221 | * |
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222 | * libpng versions 1.0.7, July 1, 2000, through 1.2.5, October 3, 2002, are |
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223 | * Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are |
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224 | * distributed according to the same disclaimer and license as libpng-1.0.6 |
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225 | * with the following individuals added to the list of Contributing Authors: |
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226 | * |
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227 | * Simon-Pierre Cadieux |
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228 | * Eric S. Raymond |
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229 | * Gilles Vollant |
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230 | * |
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231 | * and with the following additions to the disclaimer: |
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232 | * |
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233 | * There is no warranty against interference with your enjoyment of the |
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234 | * library or against infringement. There is no warranty that our |
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235 | * efforts or the library will fulfill any of your particular purposes |
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236 | * or needs. This library is provided with all faults, and the entire |
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237 | * risk of satisfactory quality, performance, accuracy, and effort is with |
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238 | * the user. |
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239 | * |
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240 | * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are |
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241 | * Copyright (c) 1998, 1999, 2000 Glenn Randers-Pehrson, and are |
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242 | * distributed according to the same disclaimer and license as libpng-0.96, |
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243 | * with the following individuals added to the list of Contributing Authors: |
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244 | * |
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245 | * Tom Lane |
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246 | * Glenn Randers-Pehrson |
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247 | * Willem van Schaik |
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248 | * |
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249 | * libpng versions 0.89, June 1996, through 0.96, May 1997, are |
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250 | * Copyright (c) 1996, 1997 Andreas Dilger |
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251 | * Distributed according to the same disclaimer and license as libpng-0.88, |
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252 | * with the following individuals added to the list of Contributing Authors: |
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253 | * |
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254 | * John Bowler |
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255 | * Kevin Bracey |
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256 | * Sam Bushell |
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257 | * Magnus Holmgren |
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258 | * Greg Roelofs |
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259 | * Tom Tanner |
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260 | * |
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261 | * libpng versions 0.5, May 1995, through 0.88, January 1996, are |
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262 | * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc. |
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263 | * |
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264 | * For the purposes of this copyright and license, "Contributing Authors" |
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265 | * is defined as the following set of individuals: |
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266 | * |
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267 | * Andreas Dilger |
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268 | * Dave Martindale |
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269 | * Guy Eric Schalnat |
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270 | * Paul Schmidt |
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271 | * Tim Wegner |
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272 | * |
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273 | * The PNG Reference Library is supplied "AS IS". The Contributing Authors |
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274 | * and Group 42, Inc. disclaim all warranties, expressed or implied, |
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275 | * including, without limitation, the warranties of merchantability and of |
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276 | * fitness for any purpose. The Contributing Authors and Group 42, Inc. |
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277 | * assume no liability for direct, indirect, incidental, special, exemplary, |
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278 | * or consequential damages, which may result from the use of the PNG |
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279 | * Reference Library, even if advised of the possibility of such damage. |
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280 | * |
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281 | * Permission is hereby granted to use, copy, modify, and distribute this |
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282 | * source code, or portions hereof, for any purpose, without fee, subject |
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283 | * to the following restrictions: |
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284 | * |
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285 | * 1. The origin of this source code must not be misrepresented. |
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286 | * |
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287 | * 2. Altered versions must be plainly marked as such and must not |
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288 | * be misrepresented as being the original source. |
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289 | * |
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290 | * 3. This Copyright notice may not be removed or altered from |
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291 | * any source or altered source distribution. |
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292 | * |
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293 | * The Contributing Authors and Group 42, Inc. specifically permit, without |
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294 | * fee, and encourage the use of this source code as a component to |
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295 | * supporting the PNG file format in commercial products. If you use this |
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296 | * source code in a product, acknowledgment is not required but would be |
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297 | * appreciated. |
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298 | */ |
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299 | |||
300 | |||
301 | * A "png_get_copyright" function is available, for convenient use in "about" |
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302 | * boxes and the like: |
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303 | * |
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304 | * printf("%s", png_get_copyright(NULL)); |
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305 | * |
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306 | * Also, the PNG logo (in PNG format, of course) is supplied in the |
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307 | * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31). |
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308 | */ |
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309 | |||
310 | |||
311 | * Libpng is OSI Certified Open Source Software. OSI Certified is a |
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312 | * certification mark of the Open Source Initiative. |
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313 | */ |
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314 | |||
315 | |||
316 | * The contributing authors would like to thank all those who helped |
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317 | * with testing, bug fixes, and patience. This wouldn't have been |
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318 | * possible without all of you. |
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319 | * |
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320 | * Thanks to Frank J. T. Wojcik for helping with the documentation. |
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321 | */ |
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322 | |||
323 | |||
324 | * Y2K compliance in libpng: |
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325 | * ========================= |
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326 | * |
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327 | * September 14, 2013 |
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328 | * |
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329 | * Since the PNG Development group is an ad-hoc body, we can't make |
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330 | * an official declaration. |
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331 | * |
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332 | * This is your unofficial assurance that libpng from version 0.71 and |
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333 | * upward through 1.6.5 are Y2K compliant. It is my belief that |
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334 | * earlier versions were also Y2K compliant. |
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335 | * |
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336 | * Libpng only has two year fields. One is a 2-byte unsigned integer |
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337 | * that will hold years up to 65535. The other, which is deprecated, |
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338 | * holds the date in text format, and will hold years up to 9999. |
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339 | * |
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340 | * The integer is |
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341 | * "png_uint_16 year" in png_time_struct. |
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342 | * |
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343 | * The string is |
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344 | * "char time_buffer[29]" in png_struct. This is no longer used |
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345 | * in libpng-1.6.x and will be removed from libpng-1.7.0. |
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346 | * |
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347 | * There are seven time-related functions: |
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348 | * png.c: png_convert_to_rfc_1123_buffer() in png.c |
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349 | * (formerly png_convert_to_rfc_1123() prior to libpng-1.5.x and |
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350 | * png_convert_to_rfc_1152() in error prior to libpng-0.98) |
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351 | * png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c |
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352 | * png_convert_from_time_t() in pngwrite.c |
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353 | * png_get_tIME() in pngget.c |
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354 | * png_handle_tIME() in pngrutil.c, called in pngread.c |
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355 | * png_set_tIME() in pngset.c |
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356 | * png_write_tIME() in pngwutil.c, called in pngwrite.c |
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357 | * |
||
358 | * All handle dates properly in a Y2K environment. The |
||
359 | * png_convert_from_time_t() function calls gmtime() to convert from system |
||
360 | * clock time, which returns (year - 1900), which we properly convert to |
||
361 | * the full 4-digit year. There is a possibility that libpng applications |
||
362 | * are not passing 4-digit years into the png_convert_to_rfc_1123_buffer() |
||
363 | * function, or that they are incorrectly passing only a 2-digit year |
||
364 | * instead of "year - 1900" into the png_convert_from_struct_tm() function, |
||
365 | * but this is not under our control. The libpng documentation has always |
||
366 | * stated that it works with 4-digit years, and the APIs have been |
||
367 | * documented as such. |
||
368 | * |
||
369 | * The tIME chunk itself is also Y2K compliant. It uses a 2-byte unsigned |
||
370 | * integer to hold the year, and can hold years as large as 65535. |
||
371 | * |
||
372 | * zlib, upon which libpng depends, is also Y2K compliant. It contains |
||
373 | * no date-related code. |
||
374 | * |
||
375 | * Glenn Randers-Pehrson |
||
376 | * libpng maintainer |
||
377 | * PNG Development Group |
||
378 | */ |
||
379 | |||
380 | |||
381 | #define PNG_H |
||
382 | |||
383 | |||
384 | * describes how to use libpng, and the file example.c summarizes it |
||
385 | * with some code on which to build. This file is useful for looking |
||
386 | * at the actual function definitions and structure components. |
||
387 | * |
||
388 | * If you just need to read a PNG file and don't want to read the documentation |
||
389 | * skip to the end of this file and read the section entitled 'simplified API'. |
||
390 | */ |
||
391 | |||
392 | |||
393 | #define PNG_LIBPNG_VER_STRING "1.6.5" |
||
394 | #define PNG_HEADER_VERSION_STRING \ |
||
395 | " libpng version 1.6.5 - September 14, 2013\n" |
||
396 | |||
397 | |||
398 | #define PNG_LIBPNG_VER_DLLNUM 16 |
||
399 | |||
400 | |||
401 | #define PNG_LIBPNG_VER_MAJOR 1 |
||
402 | #define PNG_LIBPNG_VER_MINOR 6 |
||
403 | #define PNG_LIBPNG_VER_RELEASE 5 |
||
404 | |||
405 | |||
406 | * PNG_LIBPNG_VER_STRING, omitting any leading zero: |
||
407 | */ |
||
408 | |||
409 | |||
410 | |||
411 | |||
412 | #define PNG_LIBPNG_BUILD_ALPHA 1 |
||
413 | #define PNG_LIBPNG_BUILD_BETA 2 |
||
414 | #define PNG_LIBPNG_BUILD_RC 3 |
||
415 | #define PNG_LIBPNG_BUILD_STABLE 4 |
||
416 | #define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7 |
||
417 | |||
418 | |||
419 | #define PNG_LIBPNG_BUILD_PATCH 8 /* Can be OR'ed with |
||
420 | PNG_LIBPNG_BUILD_STABLE only */ |
||
421 | #define PNG_LIBPNG_BUILD_PRIVATE 16 /* Cannot be OR'ed with |
||
422 | PNG_LIBPNG_BUILD_SPECIAL */ |
||
423 | #define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with |
||
424 | PNG_LIBPNG_BUILD_PRIVATE */ |
||
425 | |||
426 | |||
427 | |||
428 | |||
429 | * We must not include leading zeros. |
||
430 | * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only |
||
431 | * version 1.0.0 was mis-numbered 100 instead of 10000). From |
||
432 | * version 1.0.1 it's xxyyzz, where x=major, y=minor, z=release |
||
433 | */ |
||
434 | #define PNG_LIBPNG_VER 10605 /* 1.6.5 */ |
||
435 | |||
436 | |||
437 | * the library has been built. |
||
438 | */ |
||
439 | #ifndef PNGLCONF_H |
||
440 | /* If pnglibconf.h is missing, you can |
||
441 | * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h |
||
442 | */ |
||
443 | # include "pnglibconf.h" |
||
444 | #endif |
||
445 | |||
446 | |||
447 | /* Machine specific configuration. */ |
||
448 | # include "pngconf.h" |
||
449 | #endif |
||
450 | |||
451 | |||
452 | * Added at libpng-1.2.8 |
||
453 | * |
||
454 | * Ref MSDN: Private as priority over Special |
||
455 | * VS_FF_PRIVATEBUILD File *was not* built using standard release |
||
456 | * procedures. If this value is given, the StringFileInfo block must |
||
457 | * contain a PrivateBuild string. |
||
458 | * |
||
459 | * VS_FF_SPECIALBUILD File *was* built by the original company using |
||
460 | * standard release procedures but is a variation of the standard |
||
461 | * file of the same version number. If this value is given, the |
||
462 | * StringFileInfo block must contain a SpecialBuild string. |
||
463 | */ |
||
464 | |||
465 | |||
466 | # define PNG_LIBPNG_BUILD_TYPE \ |
||
467 | (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_PRIVATE) |
||
468 | #else |
||
469 | # ifdef PNG_LIBPNG_SPECIALBUILD |
||
470 | # define PNG_LIBPNG_BUILD_TYPE \ |
||
471 | (PNG_LIBPNG_BUILD_BASE_TYPE | PNG_LIBPNG_BUILD_SPECIAL) |
||
472 | # else |
||
473 | # define PNG_LIBPNG_BUILD_TYPE (PNG_LIBPNG_BUILD_BASE_TYPE) |
||
474 | # endif |
||
475 | #endif |
||
476 | |||
477 | |||
478 | |||
479 | |||
480 | #ifdef __cplusplus |
||
481 | extern "C" { |
||
482 | #endif /* __cplusplus */ |
||
483 | |||
484 | |||
485 | * the version above. |
||
486 | */ |
||
487 | #define png_libpng_ver png_get_header_ver(NULL) |
||
488 | |||
489 | |||
490 | * |
||
491 | * 1. Any configuration options that can be specified by for the application |
||
492 | * code when it is built. (Build time configuration is in pnglibconf.h) |
||
493 | * 2. Type definitions (base types are defined in pngconf.h), structure |
||
494 | * definitions. |
||
495 | * 3. Exported library functions. |
||
496 | * 4. Simplified API. |
||
497 | * |
||
498 | * The library source code has additional files (principally pngpriv.h) that |
||
499 | * allow configuration of the library. |
||
500 | */ |
||
501 | /* Section 1: run time configuration |
||
502 | * See pnglibconf.h for build time configuration |
||
503 | * |
||
504 | * Run time configuration allows the application to choose between |
||
505 | * implementations of certain arithmetic APIs. The default is set |
||
506 | * at build time and recorded in pnglibconf.h, but it is safe to |
||
507 | * override these (and only these) settings. Note that this won't |
||
508 | * change what the library does, only application code, and the |
||
509 | * settings can (and probably should) be made on a per-file basis |
||
510 | * by setting the #defines before including png.h |
||
511 | * |
||
512 | * Use macros to read integers from PNG data or use the exported |
||
513 | * functions? |
||
514 | * PNG_USE_READ_MACROS: use the macros (see below) Note that |
||
515 | * the macros evaluate their argument multiple times. |
||
516 | * PNG_NO_USE_READ_MACROS: call the relevant library function. |
||
517 | * |
||
518 | * Use the alternative algorithm for compositing alpha samples that |
||
519 | * does not use division? |
||
520 | * PNG_READ_COMPOSITE_NODIV_SUPPORTED: use the 'no division' |
||
521 | * algorithm. |
||
522 | * PNG_NO_READ_COMPOSITE_NODIV: use the 'division' algorithm. |
||
523 | * |
||
524 | * How to handle benign errors if PNG_ALLOW_BENIGN_ERRORS is |
||
525 | * false? |
||
526 | * PNG_ALLOW_BENIGN_ERRORS: map calls to the benign error |
||
527 | * APIs to png_warning. |
||
528 | * Otherwise the calls are mapped to png_error. |
||
529 | */ |
||
530 | |||
531 | |||
532 | * constants. |
||
533 | * See pngconf.h for base types that vary by machine/system |
||
534 | */ |
||
535 | |||
536 | |||
537 | * do not agree upon the version number. |
||
538 | */ |
||
539 | typedef char* png_libpng_version_1_6_5; |
||
540 | |||
541 | |||
542 | * |
||
543 | * png_struct is the cache of information used while reading or writing a single |
||
544 | * PNG file. One of these is always required, although the simplified API |
||
545 | * (below) hides the creation and destruction of it. |
||
546 | */ |
||
547 | typedef struct png_struct_def png_struct; |
||
548 | typedef const png_struct * png_const_structp; |
||
549 | typedef png_struct * png_structp; |
||
550 | typedef png_struct * * png_structpp; |
||
551 | |||
552 | |||
553 | * or more of these must exist while reading or creating a PNG file. The |
||
554 | * information is not used by libpng during read but is used to control what |
||
555 | * gets written when a PNG file is created. "png_get_" function calls read |
||
556 | * information during read and "png_set_" functions calls write information |
||
557 | * when creating a PNG. |
||
558 | * been moved into a separate header file that is not accessible to |
||
559 | * applications. Read libpng-manual.txt or libpng.3 for more info. |
||
560 | */ |
||
561 | typedef struct png_info_def png_info; |
||
562 | typedef png_info * png_infop; |
||
563 | typedef const png_info * png_const_infop; |
||
564 | typedef png_info * * png_infopp; |
||
565 | |||
566 | |||
567 | * names ending 'rp' are identical pointer types except that the pointer is |
||
568 | * marked 'restrict', which means that it is the only pointer to the object |
||
569 | * passed to the function. Applications should not use the 'restrict' types; |
||
570 | * it is always valid to pass 'p' to a pointer with a function argument of the |
||
571 | * corresponding 'rp' type. Different compilers have different rules with |
||
572 | * regard to type matching in the presence of 'restrict'. For backward |
||
573 | * compatibility libpng callbacks never have 'restrict' in their parameters and, |
||
574 | * consequentially, writing portable application code is extremely difficult if |
||
575 | * an attempt is made to use 'restrict'. |
||
576 | */ |
||
577 | typedef png_struct * PNG_RESTRICT png_structrp; |
||
578 | typedef const png_struct * PNG_RESTRICT png_const_structrp; |
||
579 | typedef png_info * PNG_RESTRICT png_inforp; |
||
580 | typedef const png_info * PNG_RESTRICT png_const_inforp; |
||
581 | |||
582 | |||
583 | * exact size) is not important, although the size of the fields need to |
||
584 | * be png_byte or png_uint_16 (as defined below). |
||
585 | */ |
||
586 | typedef struct png_color_struct |
||
587 | { |
||
588 | png_byte red; |
||
589 | png_byte green; |
||
590 | png_byte blue; |
||
591 | } png_color; |
||
592 | typedef png_color * png_colorp; |
||
593 | typedef const png_color * png_const_colorp; |
||
594 | typedef png_color * * png_colorpp; |
||
595 | |||
596 | |||
597 | { |
||
598 | png_byte index; /* used for palette files */ |
||
599 | png_uint_16 red; /* for use in red green blue files */ |
||
600 | png_uint_16 green; |
||
601 | png_uint_16 blue; |
||
602 | png_uint_16 gray; /* for use in grayscale files */ |
||
603 | } png_color_16; |
||
604 | typedef png_color_16 * png_color_16p; |
||
605 | typedef const png_color_16 * png_const_color_16p; |
||
606 | typedef png_color_16 * * png_color_16pp; |
||
607 | |||
608 | |||
609 | { |
||
610 | png_byte red; /* for use in red green blue files */ |
||
611 | png_byte green; |
||
612 | png_byte blue; |
||
613 | png_byte gray; /* for use in grayscale files */ |
||
614 | png_byte alpha; /* for alpha channel files */ |
||
615 | } png_color_8; |
||
616 | typedef png_color_8 * png_color_8p; |
||
617 | typedef const png_color_8 * png_const_color_8p; |
||
618 | typedef png_color_8 * * png_color_8pp; |
||
619 | |||
620 | |||
621 | * The following two structures are used for the in-core representation |
||
622 | * of sPLT chunks. |
||
623 | */ |
||
624 | typedef struct png_sPLT_entry_struct |
||
625 | { |
||
626 | png_uint_16 red; |
||
627 | png_uint_16 green; |
||
628 | png_uint_16 blue; |
||
629 | png_uint_16 alpha; |
||
630 | png_uint_16 frequency; |
||
631 | } png_sPLT_entry; |
||
632 | typedef png_sPLT_entry * png_sPLT_entryp; |
||
633 | typedef const png_sPLT_entry * png_const_sPLT_entryp; |
||
634 | typedef png_sPLT_entry * * png_sPLT_entrypp; |
||
635 | |||
636 | |||
637 | * occupy the LSB of their respective members, and the MSB of each member |
||
638 | * is zero-filled. The frequency member always occupies the full 16 bits. |
||
639 | */ |
||
640 | |||
641 | |||
642 | { |
||
643 | png_charp name; /* palette name */ |
||
644 | png_byte depth; /* depth of palette samples */ |
||
645 | png_sPLT_entryp entries; /* palette entries */ |
||
646 | png_int_32 nentries; /* number of palette entries */ |
||
647 | } png_sPLT_t; |
||
648 | typedef png_sPLT_t * png_sPLT_tp; |
||
649 | typedef const png_sPLT_t * png_const_sPLT_tp; |
||
650 | typedef png_sPLT_t * * png_sPLT_tpp; |
||
651 | |||
652 | |||
653 | /* png_text holds the contents of a text/ztxt/itxt chunk in a PNG file, |
||
654 | * and whether that contents is compressed or not. The "key" field |
||
655 | * points to a regular zero-terminated C string. The "text" fields can be a |
||
656 | * regular C string, an empty string, or a NULL pointer. |
||
657 | * However, the structure returned by png_get_text() will always contain |
||
658 | * the "text" field as a regular zero-terminated C string (possibly |
||
659 | * empty), never a NULL pointer, so it can be safely used in printf() and |
||
660 | * other string-handling functions. Note that the "itxt_length", "lang", and |
||
661 | * "lang_key" members of the structure only exist when the library is built |
||
662 | * with iTXt chunk support. Prior to libpng-1.4.0 the library was built by |
||
663 | * default without iTXt support. Also note that when iTXt *is* supported, |
||
664 | * the "lang" and "lang_key" fields contain NULL pointers when the |
||
665 | * "compression" field contains * PNG_TEXT_COMPRESSION_NONE or |
||
666 | * PNG_TEXT_COMPRESSION_zTXt. Note that the "compression value" is not the |
||
667 | * same as what appears in the PNG tEXt/zTXt/iTXt chunk's "compression flag" |
||
668 | * which is always 0 or 1, or its "compression method" which is always 0. |
||
669 | */ |
||
670 | typedef struct png_text_struct |
||
671 | { |
||
672 | int compression; /* compression value: |
||
673 | -1: tEXt, none |
||
674 | 0: zTXt, deflate |
||
675 | 1: iTXt, none |
||
676 | 2: iTXt, deflate */ |
||
677 | png_charp key; /* keyword, 1-79 character description of "text" */ |
||
678 | png_charp text; /* comment, may be an empty string (ie "") |
||
679 | or a NULL pointer */ |
||
680 | png_size_t text_length; /* length of the text string */ |
||
681 | png_size_t itxt_length; /* length of the itxt string */ |
||
682 | png_charp lang; /* language code, 0-79 characters |
||
683 | or a NULL pointer */ |
||
684 | png_charp lang_key; /* keyword translated UTF-8 string, 0 or more |
||
685 | chars or a NULL pointer */ |
||
686 | } png_text; |
||
687 | typedef png_text * png_textp; |
||
688 | typedef const png_text * png_const_textp; |
||
689 | typedef png_text * * png_textpp; |
||
690 | #endif |
||
691 | |||
692 | |||
693 | * The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed. */ |
||
694 | #define PNG_TEXT_COMPRESSION_NONE_WR -3 |
||
695 | #define PNG_TEXT_COMPRESSION_zTXt_WR -2 |
||
696 | #define PNG_TEXT_COMPRESSION_NONE -1 |
||
697 | #define PNG_TEXT_COMPRESSION_zTXt 0 |
||
698 | #define PNG_ITXT_COMPRESSION_NONE 1 |
||
699 | #define PNG_ITXT_COMPRESSION_zTXt 2 |
||
700 | #define PNG_TEXT_COMPRESSION_LAST 3 /* Not a valid value */ |
||
701 | |||
702 | |||
703 | * Two conversions are provided, both from time_t and struct tm. There |
||
704 | * is no portable way to convert to either of these structures, as far |
||
705 | * as I know. If you know of a portable way, send it to me. As a side |
||
706 | * note - PNG has always been Year 2000 compliant! |
||
707 | */ |
||
708 | typedef struct png_time_struct |
||
709 | { |
||
710 | png_uint_16 year; /* full year, as in, 1995 */ |
||
711 | png_byte month; /* month of year, 1 - 12 */ |
||
712 | png_byte day; /* day of month, 1 - 31 */ |
||
713 | png_byte hour; /* hour of day, 0 - 23 */ |
||
714 | png_byte minute; /* minute of hour, 0 - 59 */ |
||
715 | png_byte second; /* second of minute, 0 - 60 (for leap seconds) */ |
||
716 | } png_time; |
||
717 | typedef png_time * png_timep; |
||
718 | typedef const png_time * png_const_timep; |
||
719 | typedef png_time * * png_timepp; |
||
720 | |||
721 | |||
722 | /* png_unknown_chunk is a structure to hold queued chunks for which there is |
||
723 | * no specific support. The idea is that we can use this to queue |
||
724 | * up private chunks for output even though the library doesn't actually |
||
725 | * know about their semantics. |
||
726 | * |
||
727 | * The data in the structure is set by libpng on read and used on write. |
||
728 | */ |
||
729 | typedef struct png_unknown_chunk_t |
||
730 | { |
||
731 | png_byte name[5]; /* Textual chunk name with '\0' terminator */ |
||
732 | png_byte *data; /* Data, should not be modified on read! */ |
||
733 | png_size_t size; |
||
734 | |||
735 | |||
736 | * Notice that on read it is set by libpng however the values stored have |
||
737 | * more bits set than are listed below. Always treat the value as a |
||
738 | * bitmask. On write set only one bit - setting multiple bits may cause the |
||
739 | * chunk to be written in multiple places. |
||
740 | */ |
||
741 | png_byte location; /* mode of operation at read time */ |
||
742 | } |
||
743 | png_unknown_chunk; |
||
744 | |||
745 | |||
746 | typedef const png_unknown_chunk * png_const_unknown_chunkp; |
||
747 | typedef png_unknown_chunk * * png_unknown_chunkpp; |
||
748 | #endif |
||
749 | |||
750 | |||
751 | #define PNG_HAVE_IHDR 0x01 |
||
752 | #define PNG_HAVE_PLTE 0x02 |
||
753 | #define PNG_AFTER_IDAT 0x08 |
||
754 | |||
755 | |||
756 | #define PNG_UINT_31_MAX ((png_uint_32)0x7fffffffL) |
||
757 | #define PNG_UINT_32_MAX ((png_uint_32)(-1)) |
||
758 | #define PNG_SIZE_MAX ((png_size_t)(-1)) |
||
759 | |||
760 | |||
761 | * PNG specification manner (x100000) |
||
762 | */ |
||
763 | #define PNG_FP_1 100000 |
||
764 | #define PNG_FP_HALF 50000 |
||
765 | #define PNG_FP_MAX ((png_fixed_point)0x7fffffffL) |
||
766 | #define PNG_FP_MIN (-PNG_FP_MAX) |
||
767 | |||
768 | |||
769 | /* color type masks */ |
||
770 | #define PNG_COLOR_MASK_PALETTE 1 |
||
771 | #define PNG_COLOR_MASK_COLOR 2 |
||
772 | #define PNG_COLOR_MASK_ALPHA 4 |
||
773 | |||
774 | |||
775 | #define PNG_COLOR_TYPE_GRAY 0 |
||
776 | #define PNG_COLOR_TYPE_PALETTE (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE) |
||
777 | #define PNG_COLOR_TYPE_RGB (PNG_COLOR_MASK_COLOR) |
||
778 | #define PNG_COLOR_TYPE_RGB_ALPHA (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA) |
||
779 | #define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA) |
||
780 | /* aliases */ |
||
781 | #define PNG_COLOR_TYPE_RGBA PNG_COLOR_TYPE_RGB_ALPHA |
||
782 | #define PNG_COLOR_TYPE_GA PNG_COLOR_TYPE_GRAY_ALPHA |
||
783 | |||
784 | |||
785 | #define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */ |
||
786 | #define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE |
||
787 | |||
788 | |||
789 | #define PNG_FILTER_TYPE_BASE 0 /* Single row per-byte filtering */ |
||
790 | #define PNG_INTRAPIXEL_DIFFERENCING 64 /* Used only in MNG datastreams */ |
||
791 | #define PNG_FILTER_TYPE_DEFAULT PNG_FILTER_TYPE_BASE |
||
792 | |||
793 | |||
794 | #define PNG_INTERLACE_NONE 0 /* Non-interlaced image */ |
||
795 | #define PNG_INTERLACE_ADAM7 1 /* Adam7 interlacing */ |
||
796 | #define PNG_INTERLACE_LAST 2 /* Not a valid value */ |
||
797 | |||
798 | |||
799 | #define PNG_OFFSET_PIXEL 0 /* Offset in pixels */ |
||
800 | #define PNG_OFFSET_MICROMETER 1 /* Offset in micrometers (1/10^6 meter) */ |
||
801 | #define PNG_OFFSET_LAST 2 /* Not a valid value */ |
||
802 | |||
803 | |||
804 | #define PNG_EQUATION_LINEAR 0 /* Linear transformation */ |
||
805 | #define PNG_EQUATION_BASE_E 1 /* Exponential base e transform */ |
||
806 | #define PNG_EQUATION_ARBITRARY 2 /* Arbitrary base exponential transform */ |
||
807 | #define PNG_EQUATION_HYPERBOLIC 3 /* Hyperbolic sine transformation */ |
||
808 | #define PNG_EQUATION_LAST 4 /* Not a valid value */ |
||
809 | |||
810 | |||
811 | #define PNG_SCALE_UNKNOWN 0 /* unknown unit (image scale) */ |
||
812 | #define PNG_SCALE_METER 1 /* meters per pixel */ |
||
813 | #define PNG_SCALE_RADIAN 2 /* radians per pixel */ |
||
814 | #define PNG_SCALE_LAST 3 /* Not a valid value */ |
||
815 | |||
816 | |||
817 | #define PNG_RESOLUTION_UNKNOWN 0 /* pixels/unknown unit (aspect ratio) */ |
||
818 | #define PNG_RESOLUTION_METER 1 /* pixels/meter */ |
||
819 | #define PNG_RESOLUTION_LAST 2 /* Not a valid value */ |
||
820 | |||
821 | |||
822 | #define PNG_sRGB_INTENT_PERCEPTUAL 0 |
||
823 | #define PNG_sRGB_INTENT_RELATIVE 1 |
||
824 | #define PNG_sRGB_INTENT_SATURATION 2 |
||
825 | #define PNG_sRGB_INTENT_ABSOLUTE 3 |
||
826 | #define PNG_sRGB_INTENT_LAST 4 /* Not a valid value */ |
||
827 | |||
828 | |||
829 | #define PNG_KEYWORD_MAX_LENGTH 79 |
||
830 | |||
831 | |||
832 | #define PNG_MAX_PALETTE_LENGTH 256 |
||
833 | |||
834 | |||
835 | * from the PNG header, or if the application has filled in the corresponding |
||
836 | * data in the info_struct to be written into the output file. The values |
||
837 | * of the PNG_INFO_ |
||
838 | */ |
||
839 | #define PNG_INFO_gAMA 0x0001 |
||
840 | #define PNG_INFO_sBIT 0x0002 |
||
841 | #define PNG_INFO_cHRM 0x0004 |
||
842 | #define PNG_INFO_PLTE 0x0008 |
||
843 | #define PNG_INFO_tRNS 0x0010 |
||
844 | #define PNG_INFO_bKGD 0x0020 |
||
845 | #define PNG_INFO_hIST 0x0040 |
||
846 | #define PNG_INFO_pHYs 0x0080 |
||
847 | #define PNG_INFO_oFFs 0x0100 |
||
848 | #define PNG_INFO_tIME 0x0200 |
||
849 | #define PNG_INFO_pCAL 0x0400 |
||
850 | #define PNG_INFO_sRGB 0x0800 /* GR-P, 0.96a */ |
||
851 | #define PNG_INFO_iCCP 0x1000 /* ESR, 1.0.6 */ |
||
852 | #define PNG_INFO_sPLT 0x2000 /* ESR, 1.0.6 */ |
||
853 | #define PNG_INFO_sCAL 0x4000 /* ESR, 1.0.6 */ |
||
854 | #define PNG_INFO_IDAT 0x8000 /* ESR, 1.0.6 */ |
||
855 | |||
856 | |||
857 | * change these values for the row. It also should enable using |
||
858 | * the routines for other purposes. |
||
859 | */ |
||
860 | typedef struct png_row_info_struct |
||
861 | { |
||
862 | png_uint_32 width; /* width of row */ |
||
863 | png_size_t rowbytes; /* number of bytes in row */ |
||
864 | png_byte color_type; /* color type of row */ |
||
865 | png_byte bit_depth; /* bit depth of row */ |
||
866 | png_byte channels; /* number of channels (1, 2, 3, or 4) */ |
||
867 | png_byte pixel_depth; /* bits per pixel (depth * channels) */ |
||
868 | } png_row_info; |
||
869 | |||
870 | |||
871 | typedef png_row_info * * png_row_infopp; |
||
872 | |||
873 | |||
874 | * that allow the user to override the default I/O functions with his or her |
||
875 | * own. The png_error_ptr type should match that of user-supplied warning |
||
876 | * and error functions, while the png_rw_ptr type should match that of the |
||
877 | * user read/write data functions. Note that the 'write' function must not |
||
878 | * modify the buffer it is passed. The 'read' function, on the other hand, is |
||
879 | * expected to return the read data in the buffer. |
||
880 | */ |
||
881 | typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp)); |
||
882 | typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, png_size_t)); |
||
883 | typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp)); |
||
884 | typedef PNG_CALLBACK(void, *png_read_status_ptr, (png_structp, png_uint_32, |
||
885 | int)); |
||
886 | typedef PNG_CALLBACK(void, *png_write_status_ptr, (png_structp, png_uint_32, |
||
887 | int)); |
||
888 | |||
889 | |||
890 | typedef PNG_CALLBACK(void, *png_progressive_info_ptr, (png_structp, png_infop)); |
||
891 | typedef PNG_CALLBACK(void, *png_progressive_end_ptr, (png_structp, png_infop)); |
||
892 | |||
893 | |||
894 | * png_bytep data of the row. When transforming an interlaced image the |
||
895 | * row number is the row number within the sub-image of the interlace pass, so |
||
896 | * the value will increase to the height of the sub-image (not the full image) |
||
897 | * then reset to 0 for the next pass. |
||
898 | * |
||
899 | * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to |
||
900 | * find the output pixel (x,y) given an interlaced sub-image pixel |
||
901 | * (row,col,pass). (See below for these macros.) |
||
902 | */ |
||
903 | typedef PNG_CALLBACK(void, *png_progressive_row_ptr, (png_structp, png_bytep, |
||
904 | png_uint_32, int)); |
||
905 | #endif |
||
906 | |||
907 | |||
908 | defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED) |
||
909 | typedef PNG_CALLBACK(void, *png_user_transform_ptr, (png_structp, png_row_infop, |
||
910 | png_bytep)); |
||
911 | #endif |
||
912 | |||
913 | |||
914 | typedef PNG_CALLBACK(int, *png_user_chunk_ptr, (png_structp, |
||
915 | png_unknown_chunkp)); |
||
916 | #endif |
||
917 | #ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED |
||
918 | /* not used anywhere */ |
||
919 | /* typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp)); */ |
||
920 | #endif |
||
921 | |||
922 | |||
923 | /* This must match the function definition in |
||
924 | * must include this before png.h to obtain the definition of jmp_buf. The |
||
925 | * function is required to be PNG_NORETURN, but this is not checked. If the |
||
926 | * function does return the application will crash via an abort() or similar |
||
927 | * system level call. |
||
928 | * |
||
929 | * If you get a warning here while building the library you may need to make |
||
930 | * changes to ensure that pnglibconf.h records the calling convention used by |
||
931 | * your compiler. This may be very difficult - try using a different compiler |
||
932 | * to build the library! |
||
933 | */ |
||
934 | PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef); |
||
935 | #endif |
||
936 | |||
937 | |||
938 | #define PNG_TRANSFORM_IDENTITY 0x0000 /* read and write */ |
||
939 | #define PNG_TRANSFORM_STRIP_16 0x0001 /* read only */ |
||
940 | #define PNG_TRANSFORM_STRIP_ALPHA 0x0002 /* read only */ |
||
941 | #define PNG_TRANSFORM_PACKING 0x0004 /* read and write */ |
||
942 | #define PNG_TRANSFORM_PACKSWAP 0x0008 /* read and write */ |
||
943 | #define PNG_TRANSFORM_EXPAND 0x0010 /* read only */ |
||
944 | #define PNG_TRANSFORM_INVERT_MONO 0x0020 /* read and write */ |
||
945 | #define PNG_TRANSFORM_SHIFT 0x0040 /* read and write */ |
||
946 | #define PNG_TRANSFORM_BGR 0x0080 /* read and write */ |
||
947 | #define PNG_TRANSFORM_SWAP_ALPHA 0x0100 /* read and write */ |
||
948 | #define PNG_TRANSFORM_SWAP_ENDIAN 0x0200 /* read and write */ |
||
949 | #define PNG_TRANSFORM_INVERT_ALPHA 0x0400 /* read and write */ |
||
950 | #define PNG_TRANSFORM_STRIP_FILLER 0x0800 /* write only */ |
||
951 | /* Added to libpng-1.2.34 */ |
||
952 | #define PNG_TRANSFORM_STRIP_FILLER_BEFORE PNG_TRANSFORM_STRIP_FILLER |
||
953 | #define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */ |
||
954 | /* Added to libpng-1.4.0 */ |
||
955 | #define PNG_TRANSFORM_GRAY_TO_RGB 0x2000 /* read only */ |
||
956 | /* Added to libpng-1.5.4 */ |
||
957 | #define PNG_TRANSFORM_EXPAND_16 0x4000 /* read only */ |
||
958 | #define PNG_TRANSFORM_SCALE_16 0x8000 /* read only */ |
||
959 | |||
960 | |||
961 | #define PNG_FLAG_MNG_EMPTY_PLTE 0x01 |
||
962 | #define PNG_FLAG_MNG_FILTER_64 0x04 |
||
963 | #define PNG_ALL_MNG_FEATURES 0x05 |
||
964 | |||
965 | |||
966 | * this allowed the zlib default functions to be used on Windows |
||
967 | * platforms. In 1.5 the zlib default malloc (which just calls malloc and |
||
968 | * ignores the first argument) should be completely compatible with the |
||
969 | * following. |
||
970 | */ |
||
971 | typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp, |
||
972 | png_alloc_size_t)); |
||
973 | typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp)); |
||
974 | |||
975 | |||
976 | * Here are the function definitions most commonly used. This is not |
||
977 | * the place to find out how to use libpng. See libpng-manual.txt for the |
||
978 | * full explanation, see example.c for the summary. This just provides |
||
979 | * a simple one line description of the use of each function. |
||
980 | * |
||
981 | * The PNG_EXPORT() and PNG_EXPORTA() macros used below are defined in |
||
982 | * pngconf.h and in the *.dfn files in the scripts directory. |
||
983 | * |
||
984 | * PNG_EXPORT(ordinal, type, name, (args)); |
||
985 | * |
||
986 | * ordinal: ordinal that is used while building |
||
987 | * *.def files. The ordinal value is only |
||
988 | * relevant when preprocessing png.h with |
||
989 | * the *.dfn files for building symbol table |
||
990 | * entries, and are removed by pngconf.h. |
||
991 | * type: return type of the function |
||
992 | * name: function name |
||
993 | * args: function arguments, with types |
||
994 | * |
||
995 | * When we wish to append attributes to a function prototype we use |
||
996 | * the PNG_EXPORTA() macro instead. |
||
997 | * |
||
998 | * PNG_EXPORTA(ordinal, type, name, (args), attributes); |
||
999 | * |
||
1000 | * ordinal, type, name, and args: same as in PNG_EXPORT(). |
||
1001 | * attributes: function attributes |
||
1002 | */ |
||
1003 | |||
1004 | |||
1005 | PNG_EXPORT(1, png_uint_32, png_access_version_number, (void)); |
||
1006 | |||
1007 | |||
1008 | * Handling more than 8 bytes from the beginning of the file is an error. |
||
1009 | */ |
||
1010 | PNG_EXPORT(2, void, png_set_sig_bytes, (png_structrp png_ptr, int num_bytes)); |
||
1011 | |||
1012 | |||
1013 | * PNG file. Returns zero if the supplied bytes match the 8-byte PNG |
||
1014 | * signature, and non-zero otherwise. Having num_to_check == 0 or |
||
1015 | * start > 7 will always fail (ie return non-zero). |
||
1016 | */ |
||
1017 | PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, png_size_t start, |
||
1018 | png_size_t num_to_check)); |
||
1019 | |||
1020 | |||
1021 | * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n). |
||
1022 | */ |
||
1023 | #define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n)) |
||
1024 | |||
1025 | |||
1026 | PNG_EXPORTA(4, png_structp, png_create_read_struct, |
||
1027 | (png_const_charp user_png_ver, png_voidp error_ptr, |
||
1028 | png_error_ptr error_fn, png_error_ptr warn_fn), |
||
1029 | PNG_ALLOCATED); |
||
1030 | |||
1031 | |||
1032 | PNG_EXPORTA(5, png_structp, png_create_write_struct, |
||
1033 | (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
||
1034 | png_error_ptr warn_fn), |
||
1035 | PNG_ALLOCATED); |
||
1036 | |||
1037 | |||
1038 | (png_const_structrp png_ptr)); |
||
1039 | |||
1040 | |||
1041 | png_size_t size)); |
||
1042 | |||
1043 | |||
1044 | * match up. |
||
1045 | */ |
||
1046 | #ifdef PNG_SETJMP_SUPPORTED |
||
1047 | /* This function returns the jmp_buf built in to *png_ptr. It must be |
||
1048 | * supplied with an appropriate 'longjmp' function to use on that jmp_buf |
||
1049 | * unless the default error function is overridden in which case NULL is |
||
1050 | * acceptable. The size of the jmp_buf is checked against the actual size |
||
1051 | * allocated by the library - the call will return NULL on a mismatch |
||
1052 | * indicating an ABI mismatch. |
||
1053 | */ |
||
1054 | PNG_EXPORT(8, jmp_buf*, png_set_longjmp_fn, (png_structrp png_ptr, |
||
1055 | png_longjmp_ptr longjmp_fn, size_t jmp_buf_size)); |
||
1056 | # define png_jmpbuf(png_ptr) \ |
||
1057 | (*png_set_longjmp_fn((png_ptr), longjmp, (sizeof (jmp_buf)))) |
||
1058 | #else |
||
1059 | # define png_jmpbuf(png_ptr) \ |
||
1060 | (LIBPNG_WAS_COMPILED_WITH__PNG_NO_SETJMP) |
||
1061 | #endif |
||
1062 | /* This function should be used by libpng applications in place of |
||
1063 | * longjmp(png_ptr->jmpbuf, val). If longjmp_fn() has been set, it |
||
1064 | * will use it; otherwise it will call PNG_ABORT(). This function was |
||
1065 | * added in libpng-1.5.0. |
||
1066 | */ |
||
1067 | PNG_EXPORTA(9, void, png_longjmp, (png_const_structrp png_ptr, int val), |
||
1068 | PNG_NORETURN); |
||
1069 | |||
1070 | |||
1071 | /* Reset the compression stream */ |
||
1072 | PNG_EXPORTA(10, int, png_reset_zstream, (png_structrp png_ptr), PNG_DEPRECATED); |
||
1073 | #endif |
||
1074 | |||
1075 | |||
1076 | #ifdef PNG_USER_MEM_SUPPORTED |
||
1077 | PNG_EXPORTA(11, png_structp, png_create_read_struct_2, |
||
1078 | (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
||
1079 | png_error_ptr warn_fn, |
||
1080 | png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), |
||
1081 | PNG_ALLOCATED); |
||
1082 | PNG_EXPORTA(12, png_structp, png_create_write_struct_2, |
||
1083 | (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, |
||
1084 | png_error_ptr warn_fn, |
||
1085 | png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn), |
||
1086 | PNG_ALLOCATED); |
||
1087 | #endif |
||
1088 | |||
1089 | |||
1090 | PNG_EXPORT(13, void, png_write_sig, (png_structrp png_ptr)); |
||
1091 | |||
1092 | |||
1093 | PNG_EXPORT(14, void, png_write_chunk, (png_structrp png_ptr, png_const_bytep |
||
1094 | chunk_name, png_const_bytep data, png_size_t length)); |
||
1095 | |||
1096 | |||
1097 | PNG_EXPORT(15, void, png_write_chunk_start, (png_structrp png_ptr, |
||
1098 | png_const_bytep chunk_name, png_uint_32 length)); |
||
1099 | |||
1100 | |||
1101 | PNG_EXPORT(16, void, png_write_chunk_data, (png_structrp png_ptr, |
||
1102 | png_const_bytep data, png_size_t length)); |
||
1103 | |||
1104 | |||
1105 | PNG_EXPORT(17, void, png_write_chunk_end, (png_structrp png_ptr)); |
||
1106 | |||
1107 | |||
1108 | PNG_EXPORTA(18, png_infop, png_create_info_struct, (png_const_structrp png_ptr), |
||
1109 | PNG_ALLOCATED); |
||
1110 | |||
1111 | |||
1112 | * default allocation method (typically malloc). Use is deprecated in 1.6.0 and |
||
1113 | * the API will be removed in the future. |
||
1114 | */ |
||
1115 | PNG_EXPORTA(19, void, png_info_init_3, (png_infopp info_ptr, |
||
1116 | png_size_t png_info_struct_size), PNG_DEPRECATED); |
||
1117 | |||
1118 | |||
1119 | PNG_EXPORT(20, void, png_write_info_before_PLTE, |
||
1120 | (png_structrp png_ptr, png_const_inforp info_ptr)); |
||
1121 | PNG_EXPORT(21, void, png_write_info, |
||
1122 | (png_structrp png_ptr, png_const_inforp info_ptr)); |
||
1123 | |||
1124 | |||
1125 | /* Read the information before the actual image data. */ |
||
1126 | PNG_EXPORT(22, void, png_read_info, |
||
1127 | (png_structrp png_ptr, png_inforp info_ptr)); |
||
1128 | #endif |
||
1129 | |||
1130 | |||
1131 | /* Convert to a US string format: there is no localization support in this |
||
1132 | * routine. The original implementation used a 29 character buffer in |
||
1133 | * png_struct, this will be removed in future versions. |
||
1134 | */ |
||
1135 | #if PNG_LIBPNG_VER < 10700 |
||
1136 | /* To do: remove this from libpng17 (and from libpng17/png.c and pngstruct.h) */ |
||
1137 | PNG_EXPORTA(23, png_const_charp, png_convert_to_rfc1123, (png_structrp png_ptr, |
||
1138 | png_const_timep ptime),PNG_DEPRECATED); |
||
1139 | #endif |
||
1140 | PNG_EXPORT(241, int, png_convert_to_rfc1123_buffer, (char out[29], |
||
1141 | png_const_timep ptime)); |
||
1142 | #endif |
||
1143 | |||
1144 | |||
1145 | /* Convert from a struct tm to png_time */ |
||
1146 | PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime, |
||
1147 | const struct tm * ttime)); |
||
1148 | |||
1149 | |||
1150 | PNG_EXPORT(25, void, png_convert_from_time_t, (png_timep ptime, time_t ttime)); |
||
1151 | #endif /* PNG_CONVERT_tIME_SUPPORTED */ |
||
1152 | |||
1153 | |||
1154 | /* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */ |
||
1155 | PNG_EXPORT(26, void, png_set_expand, (png_structrp png_ptr)); |
||
1156 | PNG_EXPORT(27, void, png_set_expand_gray_1_2_4_to_8, (png_structrp png_ptr)); |
||
1157 | PNG_EXPORT(28, void, png_set_palette_to_rgb, (png_structrp png_ptr)); |
||
1158 | PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structrp png_ptr)); |
||
1159 | #endif |
||
1160 | |||
1161 | |||
1162 | /* Expand to 16-bit channels, forces conversion of palette to RGB and expansion |
||
1163 | * of a tRNS chunk if present. |
||
1164 | */ |
||
1165 | PNG_EXPORT(221, void, png_set_expand_16, (png_structrp png_ptr)); |
||
1166 | #endif |
||
1167 | |||
1168 | |||
1169 | /* Use blue, green, red order for pixels. */ |
||
1170 | PNG_EXPORT(30, void, png_set_bgr, (png_structrp png_ptr)); |
||
1171 | #endif |
||
1172 | |||
1173 | |||
1174 | /* Expand the grayscale to 24-bit RGB if necessary. */ |
||
1175 | PNG_EXPORT(31, void, png_set_gray_to_rgb, (png_structrp png_ptr)); |
||
1176 | #endif |
||
1177 | |||
1178 | |||
1179 | /* Reduce RGB to grayscale. */ |
||
1180 | #define PNG_ERROR_ACTION_NONE 1 |
||
1181 | #define PNG_ERROR_ACTION_WARN 2 |
||
1182 | #define PNG_ERROR_ACTION_ERROR 3 |
||
1183 | #define PNG_RGB_TO_GRAY_DEFAULT (-1)/*for red/green coefficients*/ |
||
1184 | |||
1185 | |||
1186 | int error_action, double red, double green)) |
||
1187 | PNG_FIXED_EXPORT(33, void, png_set_rgb_to_gray_fixed, (png_structrp png_ptr, |
||
1188 | int error_action, png_fixed_point red, png_fixed_point green)) |
||
1189 | |||
1190 | |||
1191 | png_ptr)); |
||
1192 | #endif |
||
1193 | |||
1194 | |||
1195 | PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth, |
||
1196 | png_colorp palette)); |
||
1197 | #endif |
||
1198 | |||
1199 | |||
1200 | /* How the alpha channel is interpreted - this affects how the color channels of |
||
1201 | * a PNG file are returned when an alpha channel, or tRNS chunk in a palette |
||
1202 | * file, is present. |
||
1203 | * |
||
1204 | * This has no effect on the way pixels are written into a PNG output |
||
1205 | * datastream. The color samples in a PNG datastream are never premultiplied |
||
1206 | * with the alpha samples. |
||
1207 | * |
||
1208 | * The default is to return data according to the PNG specification: the alpha |
||
1209 | * channel is a linear measure of the contribution of the pixel to the |
||
1210 | * corresponding composited pixel. The gamma encoded color channels must be |
||
1211 | * scaled according to the contribution and to do this it is necessary to undo |
||
1212 | * the encoding, scale the color values, perform the composition and reencode |
||
1213 | * the values. This is the 'PNG' mode. |
||
1214 | * |
||
1215 | * The alternative is to 'associate' the alpha with the color information by |
||
1216 | * storing color channel values that have been scaled by the alpha. The |
||
1217 | * advantage is that the color channels can be resampled (the image can be |
||
1218 | * scaled) in this form. The disadvantage is that normal practice is to store |
||
1219 | * linear, not (gamma) encoded, values and this requires 16-bit channels for |
||
1220 | * still images rather than the 8-bit channels that are just about sufficient if |
||
1221 | * gamma encoding is used. In addition all non-transparent pixel values, |
||
1222 | * including completely opaque ones, must be gamma encoded to produce the final |
||
1223 | * image. This is the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' mode (the |
||
1224 | * latter being the two common names for associated alpha color channels.) |
||
1225 | * |
||
1226 | * Since it is not necessary to perform arithmetic on opaque color values so |
||
1227 | * long as they are not to be resampled and are in the final color space it is |
||
1228 | * possible to optimize the handling of alpha by storing the opaque pixels in |
||
1229 | * the PNG format (adjusted for the output color space) while storing partially |
||
1230 | * opaque pixels in the standard, linear, format. The accuracy required for |
||
1231 | * standard alpha composition is relatively low, because the pixels are |
||
1232 | * isolated, therefore typically the accuracy loss in storing 8-bit linear |
||
1233 | * values is acceptable. (This is not true if the alpha channel is used to |
||
1234 | * simulate transparency over large areas - use 16 bits or the PNG mode in |
||
1235 | * this case!) This is the 'OPTIMIZED' mode. For this mode a pixel is |
||
1236 | * treated as opaque only if the alpha value is equal to the maximum value. |
||
1237 | * |
||
1238 | * The final choice is to gamma encode the alpha channel as well. This is |
||
1239 | * broken because, in practice, no implementation that uses this choice |
||
1240 | * correctly undoes the encoding before handling alpha composition. Use this |
||
1241 | * choice only if other serious errors in the software or hardware you use |
||
1242 | * mandate it; the typical serious error is for dark halos to appear around |
||
1243 | * opaque areas of the composited PNG image because of arithmetic overflow. |
||
1244 | * |
||
1245 | * The API function png_set_alpha_mode specifies which of these choices to use |
||
1246 | * with an enumerated 'mode' value and the gamma of the required output: |
||
1247 | */ |
||
1248 | #define PNG_ALPHA_PNG 0 /* according to the PNG standard */ |
||
1249 | #define PNG_ALPHA_STANDARD 1 /* according to Porter/Duff */ |
||
1250 | #define PNG_ALPHA_ASSOCIATED 1 /* as above; this is the normal practice */ |
||
1251 | #define PNG_ALPHA_PREMULTIPLIED 1 /* as above */ |
||
1252 | #define PNG_ALPHA_OPTIMIZED 2 /* 'PNG' for opaque pixels, else 'STANDARD' */ |
||
1253 | #define PNG_ALPHA_BROKEN 3 /* the alpha channel is gamma encoded */ |
||
1254 | |||
1255 | |||
1256 | double output_gamma)) |
||
1257 | PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structrp png_ptr, |
||
1258 | int mode, png_fixed_point output_gamma)) |
||
1259 | #endif |
||
1260 | |||
1261 | |||
1262 | /* The output_gamma value is a screen gamma in libpng terminology: it expresses |
||
1263 | * how to decode the output values, not how they are encoded. The values used |
||
1264 | * correspond to the normal numbers used to describe the overall gamma of a |
||
1265 | * computer display system; for example 2.2 for an sRGB conformant system. The |
||
1266 | * values are scaled by 100000 in the _fixed version of the API (so 220000 for |
||
1267 | * sRGB.) |
||
1268 | * |
||
1269 | * The inverse of the value is always used to provide a default for the PNG file |
||
1270 | * encoding if it has no gAMA chunk and if png_set_gamma() has not been called |
||
1271 | * to override the PNG gamma information. |
||
1272 | * |
||
1273 | * When the ALPHA_OPTIMIZED mode is selected the output gamma is used to encode |
||
1274 | * opaque pixels however pixels with lower alpha values are not encoded, |
||
1275 | * regardless of the output gamma setting. |
||
1276 | * |
||
1277 | * When the standard Porter Duff handling is requested with mode 1 the output |
||
1278 | * encoding is set to be linear and the output_gamma value is only relevant |
||
1279 | * as a default for input data that has no gamma information. The linear output |
||
1280 | * encoding will be overridden if png_set_gamma() is called - the results may be |
||
1281 | * highly unexpected! |
||
1282 | * |
||
1283 | * The following numbers are derived from the sRGB standard and the research |
||
1284 | * behind it. sRGB is defined to be approximated by a PNG gAMA chunk value of |
||
1285 | * 0.45455 (1/2.2) for PNG. The value implicitly includes any viewing |
||
1286 | * correction required to take account of any differences in the color |
||
1287 | * environment of the original scene and the intended display environment; the |
||
1288 | * value expresses how to *decode* the image for display, not how the original |
||
1289 | * data was *encoded*. |
||
1290 | * |
||
1291 | * sRGB provides a peg for the PNG standard by defining a viewing environment. |
||
1292 | * sRGB itself, and earlier TV standards, actually use a more complex transform |
||
1293 | * (a linear portion then a gamma 2.4 power law) than PNG can express. (PNG is |
||
1294 | * limited to simple power laws.) By saying that an image for direct display on |
||
1295 | * an sRGB conformant system should be stored with a gAMA chunk value of 45455 |
||
1296 | * (11.3.3.2 and 11.3.3.5 of the ISO PNG specification) the PNG specification |
||
1297 | * makes it possible to derive values for other display systems and |
||
1298 | * environments. |
||
1299 | * |
||
1300 | * The Mac value is deduced from the sRGB based on an assumption that the actual |
||
1301 | * extra viewing correction used in early Mac display systems was implemented as |
||
1302 | * a power 1.45 lookup table. |
||
1303 | * |
||
1304 | * Any system where a programmable lookup table is used or where the behavior of |
||
1305 | * the final display device characteristics can be changed requires system |
||
1306 | * specific code to obtain the current characteristic. However this can be |
||
1307 | * difficult and most PNG gamma correction only requires an approximate value. |
||
1308 | * |
||
1309 | * By default, if png_set_alpha_mode() is not called, libpng assumes that all |
||
1310 | * values are unencoded, linear, values and that the output device also has a |
||
1311 | * linear characteristic. This is only very rarely correct - it is invariably |
||
1312 | * better to call png_set_alpha_mode() with PNG_DEFAULT_sRGB than rely on the |
||
1313 | * default if you don't know what the right answer is! |
||
1314 | * |
||
1315 | * The special value PNG_GAMMA_MAC_18 indicates an older Mac system (pre Mac OS |
||
1316 | * 10.6) which used a correction table to implement a somewhat lower gamma on an |
||
1317 | * otherwise sRGB system. |
||
1318 | * |
||
1319 | * Both these values are reserved (not simple gamma values) in order to allow |
||
1320 | * more precise correction internally in the future. |
||
1321 | * |
||
1322 | * NOTE: the following values can be passed to either the fixed or floating |
||
1323 | * point APIs, but the floating point API will also accept floating point |
||
1324 | * values. |
||
1325 | */ |
||
1326 | #define PNG_DEFAULT_sRGB -1 /* sRGB gamma and color space */ |
||
1327 | #define PNG_GAMMA_MAC_18 -2 /* Old Mac '1.8' gamma and color space */ |
||
1328 | #define PNG_GAMMA_sRGB 220000 /* Television standards--matches sRGB gamma */ |
||
1329 | #define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */ |
||
1330 | #endif |
||
1331 | |||
1332 | |||
1333 | * required overall gamma correction and, where necessary, alpha |
||
1334 | * premultiplication. |
||
1335 | * |
||
1336 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); |
||
1337 | * This is the default libpng handling of the alpha channel - it is not |
||
1338 | * pre-multiplied into the color components. In addition the call states |
||
1339 | * that the output is for a sRGB system and causes all PNG files without gAMA |
||
1340 | * chunks to be assumed to be encoded using sRGB. |
||
1341 | * |
||
1342 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); |
||
1343 | * In this case the output is assumed to be something like an sRGB conformant |
||
1344 | * display preceeded by a power-law lookup table of power 1.45. This is how |
||
1345 | * early Mac systems behaved. |
||
1346 | * |
||
1347 | * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR); |
||
1348 | * This is the classic Jim Blinn approach and will work in academic |
||
1349 | * environments where everything is done by the book. It has the shortcoming |
||
1350 | * of assuming that input PNG data with no gamma information is linear - this |
||
1351 | * is unlikely to be correct unless the PNG files where generated locally. |
||
1352 | * Most of the time the output precision will be so low as to show |
||
1353 | * significant banding in dark areas of the image. |
||
1354 | * |
||
1355 | * png_set_expand_16(pp); |
||
1356 | * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB); |
||
1357 | * This is a somewhat more realistic Jim Blinn inspired approach. PNG files |
||
1358 | * are assumed to have the sRGB encoding if not marked with a gamma value and |
||
1359 | * the output is always 16 bits per component. This permits accurate scaling |
||
1360 | * and processing of the data. If you know that your input PNG files were |
||
1361 | * generated locally you might need to replace PNG_DEFAULT_sRGB with the |
||
1362 | * correct value for your system. |
||
1363 | * |
||
1364 | * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB); |
||
1365 | * If you just need to composite the PNG image onto an existing background |
||
1366 | * and if you control the code that does this you can use the optimization |
||
1367 | * setting. In this case you just copy completely opaque pixels to the |
||
1368 | * output. For pixels that are not completely transparent (you just skip |
||
1369 | * those) you do the composition math using png_composite or png_composite_16 |
||
1370 | * below then encode the resultant 8-bit or 16-bit values to match the output |
||
1371 | * encoding. |
||
1372 | * |
||
1373 | * Other cases |
||
1374 | * If neither the PNG nor the standard linear encoding work for you because |
||
1375 | * of the software or hardware you use then you have a big problem. The PNG |
||
1376 | * case will probably result in halos around the image. The linear encoding |
||
1377 | * will probably result in a washed out, too bright, image (it's actually too |
||
1378 | * contrasty.) Try the ALPHA_OPTIMIZED mode above - this will probably |
||
1379 | * substantially reduce the halos. Alternatively try: |
||
1380 | * |
||
1381 | * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB); |
||
1382 | * This option will also reduce the halos, but there will be slight dark |
||
1383 | * halos round the opaque parts of the image where the background is light. |
||
1384 | * In the OPTIMIZED mode the halos will be light halos where the background |
||
1385 | * is dark. Take your pick - the halos are unavoidable unless you can get |
||
1386 | * your hardware/software fixed! (The OPTIMIZED approach is slightly |
||
1387 | * faster.) |
||
1388 | * |
||
1389 | * When the default gamma of PNG files doesn't match the output gamma. |
||
1390 | * If you have PNG files with no gamma information png_set_alpha_mode allows |
||
1391 | * you to provide a default gamma, but it also sets the ouput gamma to the |
||
1392 | * matching value. If you know your PNG files have a gamma that doesn't |
||
1393 | * match the output you can take advantage of the fact that |
||
1394 | * png_set_alpha_mode always sets the output gamma but only sets the PNG |
||
1395 | * default if it is not already set: |
||
1396 | * |
||
1397 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB); |
||
1398 | * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC); |
||
1399 | * The first call sets both the default and the output gamma values, the |
||
1400 | * second call overrides the output gamma without changing the default. This |
||
1401 | * is easier than achieving the same effect with png_set_gamma. You must use |
||
1402 | * PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will |
||
1403 | * fire if more than one call to png_set_alpha_mode and png_set_background is |
||
1404 | * made in the same read operation, however multiple calls with PNG_ALPHA_PNG |
||
1405 | * are ignored. |
||
1406 | */ |
||
1407 | |||
1408 | |||
1409 | PNG_EXPORT(36, void, png_set_strip_alpha, (png_structrp png_ptr)); |
||
1410 | #endif |
||
1411 | |||
1412 | |||
1413 | defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED) |
||
1414 | PNG_EXPORT(37, void, png_set_swap_alpha, (png_structrp png_ptr)); |
||
1415 | #endif |
||
1416 | |||
1417 | |||
1418 | defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) |
||
1419 | PNG_EXPORT(38, void, png_set_invert_alpha, (png_structrp png_ptr)); |
||
1420 | #endif |
||
1421 | |||
1422 | |||
1423 | /* Add a filler byte to 8-bit Gray or 24-bit RGB images. */ |
||
1424 | PNG_EXPORT(39, void, png_set_filler, (png_structrp png_ptr, png_uint_32 filler, |
||
1425 | int flags)); |
||
1426 | /* The values of the PNG_FILLER_ defines should NOT be changed */ |
||
1427 | # define PNG_FILLER_BEFORE 0 |
||
1428 | # define PNG_FILLER_AFTER 1 |
||
1429 | /* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */ |
||
1430 | PNG_EXPORT(40, void, png_set_add_alpha, (png_structrp png_ptr, |
||
1431 | png_uint_32 filler, int flags)); |
||
1432 | #endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */ |
||
1433 | |||
1434 | |||
1435 | /* Swap bytes in 16-bit depth files. */ |
||
1436 | PNG_EXPORT(41, void, png_set_swap, (png_structrp png_ptr)); |
||
1437 | #endif |
||
1438 | |||
1439 | |||
1440 | /* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */ |
||
1441 | PNG_EXPORT(42, void, png_set_packing, (png_structrp png_ptr)); |
||
1442 | #endif |
||
1443 | |||
1444 | |||
1445 | defined(PNG_WRITE_PACKSWAP_SUPPORTED) |
||
1446 | /* Swap packing order of pixels in bytes. */ |
||
1447 | PNG_EXPORT(43, void, png_set_packswap, (png_structrp png_ptr)); |
||
1448 | #endif |
||
1449 | |||
1450 | |||
1451 | /* Converts files to legal bit depths. */ |
||
1452 | PNG_EXPORT(44, void, png_set_shift, (png_structrp png_ptr, png_const_color_8p |
||
1453 | true_bits)); |
||
1454 | #endif |
||
1455 | |||
1456 | |||
1457 | defined(PNG_WRITE_INTERLACING_SUPPORTED) |
||
1458 | /* Have the code handle the interlacing. Returns the number of passes. |
||
1459 | * MUST be called before png_read_update_info or png_start_read_image, |
||
1460 | * otherwise it will not have the desired effect. Note that it is still |
||
1461 | * necessary to call png_read_row or png_read_rows png_get_image_height |
||
1462 | * times for each pass. |
||
1463 | */ |
||
1464 | PNG_EXPORT(45, int, png_set_interlace_handling, (png_structrp png_ptr)); |
||
1465 | #endif |
||
1466 | |||
1467 | |||
1468 | /* Invert monochrome files */ |
||
1469 | PNG_EXPORT(46, void, png_set_invert_mono, (png_structrp png_ptr)); |
||
1470 | #endif |
||
1471 | |||
1472 | |||
1473 | /* Handle alpha and tRNS by replacing with a background color. Prior to |
||
1474 | * libpng-1.5.4 this API must not be called before the PNG file header has been |
||
1475 | * read. Doing so will result in unexpected behavior and possible warnings or |
||
1476 | * errors if the PNG file contains a bKGD chunk. |
||
1477 | */ |
||
1478 | PNG_FP_EXPORT(47, void, png_set_background, (png_structrp png_ptr, |
||
1479 | png_const_color_16p background_color, int background_gamma_code, |
||
1480 | int need_expand, double background_gamma)) |
||
1481 | PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structrp png_ptr, |
||
1482 | png_const_color_16p background_color, int background_gamma_code, |
||
1483 | int need_expand, png_fixed_point background_gamma)) |
||
1484 | #endif |
||
1485 | #ifdef PNG_READ_BACKGROUND_SUPPORTED |
||
1486 | # define PNG_BACKGROUND_GAMMA_UNKNOWN 0 |
||
1487 | # define PNG_BACKGROUND_GAMMA_SCREEN 1 |
||
1488 | # define PNG_BACKGROUND_GAMMA_FILE 2 |
||
1489 | # define PNG_BACKGROUND_GAMMA_UNIQUE 3 |
||
1490 | #endif |
||
1491 | |||
1492 | |||
1493 | /* Scale a 16-bit depth file down to 8-bit, accurately. */ |
||
1494 | PNG_EXPORT(229, void, png_set_scale_16, (png_structrp png_ptr)); |
||
1495 | #endif |
||
1496 | |||
1497 | |||
1498 | #define PNG_READ_16_TO_8 SUPPORTED /* Name prior to 1.5.4 */ |
||
1499 | /* Strip the second byte of information from a 16-bit depth file. */ |
||
1500 | PNG_EXPORT(48, void, png_set_strip_16, (png_structrp png_ptr)); |
||
1501 | #endif |
||
1502 | |||
1503 | |||
1504 | /* Turn on quantizing, and reduce the palette to the number of colors |
||
1505 | * available. |
||
1506 | */ |
||
1507 | PNG_EXPORT(49, void, png_set_quantize, (png_structrp png_ptr, |
||
1508 | png_colorp palette, int num_palette, int maximum_colors, |
||
1509 | png_const_uint_16p histogram, int full_quantize)); |
||
1510 | #endif |
||
1511 | |||
1512 | |||
1513 | /* The threshold on gamma processing is configurable but hard-wired into the |
||
1514 | * library. The following is the floating point variant. |
||
1515 | */ |
||
1516 | #define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001) |
||
1517 | |||
1518 | |||
1519 | * NOTE: this API simply sets the screen and file gamma values. It will |
||
1520 | * therefore override the value for gamma in a PNG file if it is called after |
||
1521 | * the file header has been read - use with care - call before reading the PNG |
||
1522 | * file for best results! |
||
1523 | * |
||
1524 | * These routines accept the same gamma values as png_set_alpha_mode (described |
||
1525 | * above). The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either |
||
1526 | * API (floating point or fixed.) Notice, however, that the 'file_gamma' value |
||
1527 | * is the inverse of a 'screen gamma' value. |
||
1528 | */ |
||
1529 | PNG_FP_EXPORT(50, void, png_set_gamma, (png_structrp png_ptr, |
||
1530 | double screen_gamma, double override_file_gamma)) |
||
1531 | PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structrp png_ptr, |
||
1532 | png_fixed_point screen_gamma, png_fixed_point override_file_gamma)) |
||
1533 | #endif |
||
1534 | |||
1535 | |||
1536 | /* Set how many lines between output flushes - 0 for no flushing */ |
||
1537 | PNG_EXPORT(51, void, png_set_flush, (png_structrp png_ptr, int nrows)); |
||
1538 | /* Flush the current PNG output buffer */ |
||
1539 | PNG_EXPORT(52, void, png_write_flush, (png_structrp png_ptr)); |
||
1540 | #endif |
||
1541 | |||
1542 | |||
1543 | PNG_EXPORT(53, void, png_start_read_image, (png_structrp png_ptr)); |
||
1544 | |||
1545 | |||
1546 | PNG_EXPORT(54, void, png_read_update_info, (png_structrp png_ptr, |
||
1547 | png_inforp info_ptr)); |
||
1548 | |||
1549 | |||
1550 | /* Read one or more rows of image data. */ |
||
1551 | PNG_EXPORT(55, void, png_read_rows, (png_structrp png_ptr, png_bytepp row, |
||
1552 | png_bytepp display_row, png_uint_32 num_rows)); |
||
1553 | #endif |
||
1554 | |||
1555 | |||
1556 | /* Read a row of data. */ |
||
1557 | PNG_EXPORT(56, void, png_read_row, (png_structrp png_ptr, png_bytep row, |
||
1558 | png_bytep display_row)); |
||
1559 | #endif |
||
1560 | |||
1561 | |||
1562 | /* Read the whole image into memory at once. */ |
||
1563 | PNG_EXPORT(57, void, png_read_image, (png_structrp png_ptr, png_bytepp image)); |
||
1564 | #endif |
||
1565 | |||
1566 | |||
1567 | PNG_EXPORT(58, void, png_write_row, (png_structrp png_ptr, |
||
1568 | png_const_bytep row)); |
||
1569 | |||
1570 | |||
1571 | * is declared as writeable to maintain compatibility with previous versions |
||
1572 | * of libpng and to allow the 'display_row' array from read_rows to be passed |
||
1573 | * unchanged to write_rows. |
||
1574 | */ |
||
1575 | PNG_EXPORT(59, void, png_write_rows, (png_structrp png_ptr, png_bytepp row, |
||
1576 | png_uint_32 num_rows)); |
||
1577 | |||
1578 | |||
1579 | PNG_EXPORT(60, void, png_write_image, (png_structrp png_ptr, png_bytepp image)); |
||
1580 | |||
1581 | |||
1582 | PNG_EXPORT(61, void, png_write_end, (png_structrp png_ptr, |
||
1583 | png_inforp info_ptr)); |
||
1584 | |||
1585 | |||
1586 | /* Read the end of the PNG file. */ |
||
1587 | PNG_EXPORT(62, void, png_read_end, (png_structrp png_ptr, png_inforp info_ptr)); |
||
1588 | #endif |
||
1589 | |||
1590 | |||
1591 | PNG_EXPORT(63, void, png_destroy_info_struct, (png_const_structrp png_ptr, |
||
1592 | png_infopp info_ptr_ptr)); |
||
1593 | |||
1594 | |||
1595 | PNG_EXPORT(64, void, png_destroy_read_struct, (png_structpp png_ptr_ptr, |
||
1596 | png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr)); |
||
1597 | |||
1598 | |||
1599 | PNG_EXPORT(65, void, png_destroy_write_struct, (png_structpp png_ptr_ptr, |
||
1600 | png_infopp info_ptr_ptr)); |
||
1601 | |||
1602 | |||
1603 | PNG_EXPORT(66, void, png_set_crc_action, (png_structrp png_ptr, int crit_action, |
||
1604 | int ancil_action)); |
||
1605 | |||
1606 | |||
1607 | * ancillary and critical chunks, and whether to use the data contained |
||
1608 | * therein. Note that it is impossible to "discard" data in a critical |
||
1609 | * chunk. For versions prior to 0.90, the action was always error/quit, |
||
1610 | * whereas in version 0.90 and later, the action for CRC errors in ancillary |
||
1611 | * chunks is warn/discard. These values should NOT be changed. |
||
1612 | * |
||
1613 | * value action:critical action:ancillary |
||
1614 | */ |
||
1615 | #define PNG_CRC_DEFAULT 0 /* error/quit warn/discard data */ |
||
1616 | #define PNG_CRC_ERROR_QUIT 1 /* error/quit error/quit */ |
||
1617 | #define PNG_CRC_WARN_DISCARD 2 /* (INVALID) warn/discard data */ |
||
1618 | #define PNG_CRC_WARN_USE 3 /* warn/use data warn/use data */ |
||
1619 | #define PNG_CRC_QUIET_USE 4 /* quiet/use data quiet/use data */ |
||
1620 | #define PNG_CRC_NO_CHANGE 5 /* use current value use current value */ |
||
1621 | |||
1622 | |||
1623 | * libpng and the compression methods used by zlib. These functions are |
||
1624 | * mainly useful for testing, as the defaults should work with most users. |
||
1625 | * Those users who are tight on memory or want faster performance at the |
||
1626 | * expense of compression can modify them. See the compression library |
||
1627 | * header file (zlib.h) for an explination of the compression functions. |
||
1628 | */ |
||
1629 | |||
1630 | |||
1631 | * value for "method" is 0. |
||
1632 | */ |
||
1633 | PNG_EXPORT(67, void, png_set_filter, (png_structrp png_ptr, int method, |
||
1634 | int filters)); |
||
1635 | |||
1636 | |||
1637 | * are chosen so that they don't conflict with real filter types |
||
1638 | * below, in case they are supplied instead of the #defined constants. |
||
1639 | * These values should NOT be changed. |
||
1640 | */ |
||
1641 | #define PNG_NO_FILTERS 0x00 |
||
1642 | #define PNG_FILTER_NONE 0x08 |
||
1643 | #define PNG_FILTER_SUB 0x10 |
||
1644 | #define PNG_FILTER_UP 0x20 |
||
1645 | #define PNG_FILTER_AVG 0x40 |
||
1646 | #define PNG_FILTER_PAETH 0x80 |
||
1647 | #define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \ |
||
1648 | PNG_FILTER_AVG | PNG_FILTER_PAETH) |
||
1649 | |||
1650 | |||
1651 | * These defines should NOT be changed. |
||
1652 | */ |
||
1653 | #define PNG_FILTER_VALUE_NONE 0 |
||
1654 | #define PNG_FILTER_VALUE_SUB 1 |
||
1655 | #define PNG_FILTER_VALUE_UP 2 |
||
1656 | #define PNG_FILTER_VALUE_AVG 3 |
||
1657 | #define PNG_FILTER_VALUE_PAETH 4 |
||
1658 | #define PNG_FILTER_VALUE_LAST 5 |
||
1659 | |||
1660 | |||
1661 | /* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_ |
||
1662 | * defines, either the default (minimum-sum-of-absolute-differences), or |
||
1663 | * the experimental method (weighted-minimum-sum-of-absolute-differences). |
||
1664 | * |
||
1665 | * Weights are factors >= 1.0, indicating how important it is to keep the |
||
1666 | * filter type consistent between rows. Larger numbers mean the current |
||
1667 | * filter is that many times as likely to be the same as the "num_weights" |
||
1668 | * previous filters. This is cumulative for each previous row with a weight. |
||
1669 | * There needs to be "num_weights" values in "filter_weights", or it can be |
||
1670 | * NULL if the weights aren't being specified. Weights have no influence on |
||
1671 | * the selection of the first row filter. Well chosen weights can (in theory) |
||
1672 | * improve the compression for a given image. |
||
1673 | * |
||
1674 | * Costs are factors >= 1.0 indicating the relative decoding costs of a |
||
1675 | * filter type. Higher costs indicate more decoding expense, and are |
||
1676 | * therefore less likely to be selected over a filter with lower computational |
||
1677 | * costs. There needs to be a value in "filter_costs" for each valid filter |
||
1678 | * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't |
||
1679 | * setting the costs. Costs try to improve the speed of decompression without |
||
1680 | * unduly increasing the compressed image size. |
||
1681 | * |
||
1682 | * A negative weight or cost indicates the default value is to be used, and |
||
1683 | * values in the range [0.0, 1.0) indicate the value is to remain unchanged. |
||
1684 | * The default values for both weights and costs are currently 1.0, but may |
||
1685 | * change if good general weighting/cost heuristics can be found. If both |
||
1686 | * the weights and costs are set to 1.0, this degenerates the WEIGHTED method |
||
1687 | * to the UNWEIGHTED method, but with added encoding time/computation. |
||
1688 | */ |
||
1689 | PNG_FP_EXPORT(68, void, png_set_filter_heuristics, (png_structrp png_ptr, |
||
1690 | int heuristic_method, int num_weights, png_const_doublep filter_weights, |
||
1691 | png_const_doublep filter_costs)) |
||
1692 | PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed, |
||
1693 | (png_structrp png_ptr, int heuristic_method, int num_weights, |
||
1694 | png_const_fixed_point_p filter_weights, |
||
1695 | png_const_fixed_point_p filter_costs)) |
||
1696 | #endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */ |
||
1697 | |||
1698 | |||
1699 | * changed. |
||
1700 | */ |
||
1701 | #define PNG_FILTER_HEURISTIC_DEFAULT 0 /* Currently "UNWEIGHTED" */ |
||
1702 | #define PNG_FILTER_HEURISTIC_UNWEIGHTED 1 /* Used by libpng < 0.95 */ |
||
1703 | #define PNG_FILTER_HEURISTIC_WEIGHTED 2 /* Experimental feature */ |
||
1704 | #define PNG_FILTER_HEURISTIC_LAST 3 /* Not a valid value */ |
||
1705 | |||
1706 | |||
1707 | /* Set the library compression level. Currently, valid values range from |
||
1708 | * 0 - 9, corresponding directly to the zlib compression levels 0 - 9 |
||
1709 | * (0 - no compression, 9 - "maximal" compression). Note that tests have |
||
1710 | * shown that zlib compression levels 3-6 usually perform as well as level 9 |
||
1711 | * for PNG images, and do considerably fewer caclulations. In the future, |
||
1712 | * these values may not correspond directly to the zlib compression levels. |
||
1713 | */ |
||
1714 | PNG_EXPORT(69, void, png_set_compression_level, (png_structrp png_ptr, |
||
1715 | int level)); |
||
1716 | |||
1717 | |||
1718 | int mem_level)); |
||
1719 | |||
1720 | |||
1721 | int strategy)); |
||
1722 | |||
1723 | |||
1724 | * smaller value of window_bits if it can do so safely. |
||
1725 | */ |
||
1726 | PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structrp png_ptr, |
||
1727 | int window_bits)); |
||
1728 | |||
1729 | |||
1730 | int method)); |
||
1731 | #endif |
||
1732 | |||
1733 | |||
1734 | /* Also set zlib parameters for compressing non-IDAT chunks */ |
||
1735 | PNG_EXPORT(222, void, png_set_text_compression_level, (png_structrp png_ptr, |
||
1736 | int level)); |
||
1737 | |||
1738 | |||
1739 | int mem_level)); |
||
1740 | |||
1741 | |||
1742 | int strategy)); |
||
1743 | |||
1744 | |||
1745 | * smaller value of window_bits if it can do so safely. |
||
1746 | */ |
||
1747 | PNG_EXPORT(225, void, png_set_text_compression_window_bits, |
||
1748 | (png_structrp png_ptr, int window_bits)); |
||
1749 | |||
1750 | |||
1751 | int method)); |
||
1752 | #endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */ |
||
1753 | |||
1754 | |||
1755 | * handling. They are in the file pngrio.c, pngwio.c, and pngerror.c, |
||
1756 | * and call standard C I/O routines such as fread(), fwrite(), and |
||
1757 | * fprintf(). These functions can be made to use other I/O routines |
||
1758 | * at run time for those applications that need to handle I/O in a |
||
1759 | * different manner by calling png_set_???_fn(). See libpng-manual.txt for |
||
1760 | * more information. |
||
1761 | */ |
||
1762 | |||
1763 | |||
1764 | /* Initialize the input/output for the PNG file to the default functions. */ |
||
1765 | PNG_EXPORT(74, void, png_init_io, (png_structrp png_ptr, png_FILE_p fp)); |
||
1766 | #endif |
||
1767 | |||
1768 | |||
1769 | * supplied functions. If no messages are to be printed you must still |
||
1770 | * write and use replacement functions. The replacement error_fn should |
||
1771 | * still do a longjmp to the last setjmp location if you are using this |
||
1772 | * method of error handling. If error_fn or warning_fn is NULL, the |
||
1773 | * default function will be used. |
||
1774 | */ |
||
1775 | |||
1776 | |||
1777 | png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warning_fn)); |
||
1778 | |||
1779 | |||
1780 | PNG_EXPORT(76, png_voidp, png_get_error_ptr, (png_const_structrp png_ptr)); |
||
1781 | |||
1782 | |||
1783 | * If buffered output is not used, then output_flush_fn can be set to NULL. |
||
1784 | * If PNG_WRITE_FLUSH_SUPPORTED is not defined at libpng compile time |
||
1785 | * output_flush_fn will be ignored (and thus can be NULL). |
||
1786 | * It is probably a mistake to use NULL for output_flush_fn if |
||
1787 | * write_data_fn is not also NULL unless you have built libpng with |
||
1788 | * PNG_WRITE_FLUSH_SUPPORTED undefined, because in this case libpng's |
||
1789 | * default flush function, which uses the standard *FILE structure, will |
||
1790 | * be used. |
||
1791 | */ |
||
1792 | PNG_EXPORT(77, void, png_set_write_fn, (png_structrp png_ptr, png_voidp io_ptr, |
||
1793 | png_rw_ptr write_data_fn, png_flush_ptr output_flush_fn)); |
||
1794 | |||
1795 | |||
1796 | PNG_EXPORT(78, void, png_set_read_fn, (png_structrp png_ptr, png_voidp io_ptr, |
||
1797 | png_rw_ptr read_data_fn)); |
||
1798 | |||
1799 | |||
1800 | PNG_EXPORT(79, png_voidp, png_get_io_ptr, (png_const_structrp png_ptr)); |
||
1801 | |||
1802 | |||
1803 | png_read_status_ptr read_row_fn)); |
||
1804 | |||
1805 | |||
1806 | png_write_status_ptr write_row_fn)); |
||
1807 | |||
1808 | |||
1809 | /* Replace the default memory allocation functions with user supplied one(s). */ |
||
1810 | PNG_EXPORT(82, void, png_set_mem_fn, (png_structrp png_ptr, png_voidp mem_ptr, |
||
1811 | png_malloc_ptr malloc_fn, png_free_ptr free_fn)); |
||
1812 | /* Return the user pointer associated with the memory functions */ |
||
1813 | PNG_EXPORT(83, png_voidp, png_get_mem_ptr, (png_const_structrp png_ptr)); |
||
1814 | #endif |
||
1815 | |||
1816 | |||
1817 | PNG_EXPORT(84, void, png_set_read_user_transform_fn, (png_structrp png_ptr, |
||
1818 | png_user_transform_ptr read_user_transform_fn)); |
||
1819 | #endif |
||
1820 | |||
1821 | |||
1822 | PNG_EXPORT(85, void, png_set_write_user_transform_fn, (png_structrp png_ptr, |
||
1823 | png_user_transform_ptr write_user_transform_fn)); |
||
1824 | #endif |
||
1825 | |||
1826 | |||
1827 | PNG_EXPORT(86, void, png_set_user_transform_info, (png_structrp png_ptr, |
||
1828 | png_voidp user_transform_ptr, int user_transform_depth, |
||
1829 | int user_transform_channels)); |
||
1830 | /* Return the user pointer associated with the user transform functions */ |
||
1831 | PNG_EXPORT(87, png_voidp, png_get_user_transform_ptr, |
||
1832 | (png_const_structrp png_ptr)); |
||
1833 | #endif |
||
1834 | |||
1835 | |||
1836 | /* Return information about the row currently being processed. Note that these |
||
1837 | * APIs do not fail but will return unexpected results if called outside a user |
||
1838 | * transform callback. Also note that when transforming an interlaced image the |
||
1839 | * row number is the row number within the sub-image of the interlace pass, so |
||
1840 | * the value will increase to the height of the sub-image (not the full image) |
||
1841 | * then reset to 0 for the next pass. |
||
1842 | * |
||
1843 | * Use PNG_ROW_FROM_PASS_ROW(row, pass) and PNG_COL_FROM_PASS_COL(col, pass) to |
||
1844 | * find the output pixel (x,y) given an interlaced sub-image pixel |
||
1845 | * (row,col,pass). (See below for these macros.) |
||
1846 | */ |
||
1847 | PNG_EXPORT(217, png_uint_32, png_get_current_row_number, (png_const_structrp)); |
||
1848 | PNG_EXPORT(218, png_byte, png_get_current_pass_number, (png_const_structrp)); |
||
1849 | #endif |
||
1850 | |||
1851 | |||
1852 | /* This callback is called only for *unknown* chunks. If |
||
1853 | * PNG_HANDLE_AS_UNKNOWN_SUPPORTED is set then it is possible to set known |
||
1854 | * chunks to be treated as unknown, however in this case the callback must do |
||
1855 | * any processing required by the chunk (e.g. by calling the appropriate |
||
1856 | * png_set_ APIs.) |
||
1857 | * |
||
1858 | * There is no write support - on write, by default, all the chunks in the |
||
1859 | * 'unknown' list are written in the specified position. |
||
1860 | * |
||
1861 | * The integer return from the callback function is interpreted thus: |
||
1862 | * |
||
1863 | * negative: An error occured, png_chunk_error will be called. |
||
1864 | * zero: The chunk was not handled, the chunk will be saved. A critical |
||
1865 | * chunk will cause an error at this point unless it is to be saved. |
||
1866 | * positive: The chunk was handled, libpng will ignore/discard it. |
||
1867 | * |
||
1868 | * See "INTERACTION WTIH USER CHUNK CALLBACKS" below for important notes about |
||
1869 | * how this behavior will change in libpng 1.7 |
||
1870 | */ |
||
1871 | PNG_EXPORT(88, void, png_set_read_user_chunk_fn, (png_structrp png_ptr, |
||
1872 | png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn)); |
||
1873 | #endif |
||
1874 | |||
1875 | |||
1876 | PNG_EXPORT(89, png_voidp, png_get_user_chunk_ptr, (png_const_structrp png_ptr)); |
||
1877 | #endif |
||
1878 | |||
1879 | |||
1880 | /* Sets the function callbacks for the push reader, and a pointer to a |
||
1881 | * user-defined structure available to the callback functions. |
||
1882 | */ |
||
1883 | PNG_EXPORT(90, void, png_set_progressive_read_fn, (png_structrp png_ptr, |
||
1884 | png_voidp progressive_ptr, png_progressive_info_ptr info_fn, |
||
1885 | png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn)); |
||
1886 | |||
1887 | |||
1888 | PNG_EXPORT(91, png_voidp, png_get_progressive_ptr, |
||
1889 | (png_const_structrp png_ptr)); |
||
1890 | |||
1891 | |||
1892 | PNG_EXPORT(92, void, png_process_data, (png_structrp png_ptr, |
||
1893 | png_inforp info_ptr, png_bytep buffer, png_size_t buffer_size)); |
||
1894 | |||
1895 | |||
1896 | * processing of any more data. The function returns the number of bytes |
||
1897 | * remaining, excluding any that libpng has cached internally. A subsequent |
||
1898 | * call to png_process_data must supply these bytes again. If the argument |
||
1899 | * 'save' is set to true the routine will first save all the pending data and |
||
1900 | * will always return 0. |
||
1901 | */ |
||
1902 | PNG_EXPORT(219, png_size_t, png_process_data_pause, (png_structrp, int save)); |
||
1903 | |||
1904 | |||
1905 | * png_process_data. It returns the number of bytes of data to skip in the |
||
1906 | * input. Normally it will return 0, but if it returns a non-zero value the |
||
1907 | * application must skip than number of bytes of input data and pass the |
||
1908 | * following data to the next call to png_process_data. |
||
1909 | */ |
||
1910 | PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structrp)); |
||
1911 | |||
1912 | |||
1913 | /* Function that combines rows. 'new_row' is a flag that should come from |
||
1914 | * the callback and be non-NULL if anything needs to be done; the library |
||
1915 | * stores its own version of the new data internally and ignores the passed |
||
1916 | * in value. |
||
1917 | */ |
||
1918 | PNG_EXPORT(93, void, png_progressive_combine_row, (png_const_structrp png_ptr, |
||
1919 | png_bytep old_row, png_const_bytep new_row)); |
||
1920 | #endif /* PNG_READ_INTERLACING_SUPPORTED */ |
||
1921 | #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ |
||
1922 | |||
1923 | |||
1924 | png_alloc_size_t size), PNG_ALLOCATED); |
||
1925 | /* Added at libpng version 1.4.0 */ |
||
1926 | PNG_EXPORTA(95, png_voidp, png_calloc, (png_const_structrp png_ptr, |
||
1927 | png_alloc_size_t size), PNG_ALLOCATED); |
||
1928 | |||
1929 | |||
1930 | PNG_EXPORTA(96, png_voidp, png_malloc_warn, (png_const_structrp png_ptr, |
||
1931 | png_alloc_size_t size), PNG_ALLOCATED); |
||
1932 | |||
1933 | |||
1934 | PNG_EXPORT(97, void, png_free, (png_const_structrp png_ptr, png_voidp ptr)); |
||
1935 | |||
1936 | |||
1937 | PNG_EXPORT(98, void, png_free_data, (png_const_structrp png_ptr, |
||
1938 | png_inforp info_ptr, png_uint_32 free_me, int num)); |
||
1939 | |||
1940 | |||
1941 | * by libpng or by the application; this works on the png_info structure passed |
||
1942 | * in, it does not change the state for other png_info structures. |
||
1943 | * |
||
1944 | * It is unlikely that this function works correctly as of 1.6.0 and using it |
||
1945 | * may result either in memory leaks or double free of allocated data. |
||
1946 | */ |
||
1947 | PNG_EXPORTA(99, void, png_data_freer, (png_const_structrp png_ptr, |
||
1948 | png_inforp info_ptr, int freer, png_uint_32 mask), PNG_DEPRECATED); |
||
1949 | |||
1950 | |||
1951 | #define PNG_DESTROY_WILL_FREE_DATA 1 |
||
1952 | #define PNG_SET_WILL_FREE_DATA 1 |
||
1953 | #define PNG_USER_WILL_FREE_DATA 2 |
||
1954 | /* Flags for png_ptr->free_me and info_ptr->free_me */ |
||
1955 | #define PNG_FREE_HIST 0x0008 |
||
1956 | #define PNG_FREE_ICCP 0x0010 |
||
1957 | #define PNG_FREE_SPLT 0x0020 |
||
1958 | #define PNG_FREE_ROWS 0x0040 |
||
1959 | #define PNG_FREE_PCAL 0x0080 |
||
1960 | #define PNG_FREE_SCAL 0x0100 |
||
1961 | #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED |
||
1962 | # define PNG_FREE_UNKN 0x0200 |
||
1963 | #endif |
||
1964 | /* PNG_FREE_LIST 0x0400 removed in 1.6.0 because it is ignored */ |
||
1965 | #define PNG_FREE_PLTE 0x1000 |
||
1966 | #define PNG_FREE_TRNS 0x2000 |
||
1967 | #define PNG_FREE_TEXT 0x4000 |
||
1968 | #define PNG_FREE_ALL 0x7fff |
||
1969 | #define PNG_FREE_MUL 0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */ |
||
1970 | |||
1971 | |||
1972 | PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_const_structrp png_ptr, |
||
1973 | png_alloc_size_t size), PNG_ALLOCATED PNG_DEPRECATED); |
||
1974 | PNG_EXPORTA(101, void, png_free_default, (png_const_structrp png_ptr, |
||
1975 | png_voidp ptr), PNG_DEPRECATED); |
||
1976 | #endif |
||
1977 | |||
1978 | |||
1979 | /* Fatal error in PNG image of libpng - can't continue */ |
||
1980 | PNG_EXPORTA(102, void, png_error, (png_const_structrp png_ptr, |
||
1981 | png_const_charp error_message), PNG_NORETURN); |
||
1982 | |||
1983 | |||
1984 | PNG_EXPORTA(103, void, png_chunk_error, (png_const_structrp png_ptr, |
||
1985 | png_const_charp error_message), PNG_NORETURN); |
||
1986 | |||
1987 | |||
1988 | /* Fatal error in PNG image of libpng - can't continue */ |
||
1989 | PNG_EXPORTA(104, void, png_err, (png_const_structrp png_ptr), PNG_NORETURN); |
||
1990 | #endif |
||
1991 | |||
1992 | |||
1993 | /* Non-fatal error in libpng. Can continue, but may have a problem. */ |
||
1994 | PNG_EXPORT(105, void, png_warning, (png_const_structrp png_ptr, |
||
1995 | png_const_charp warning_message)); |
||
1996 | |||
1997 | |||
1998 | PNG_EXPORT(106, void, png_chunk_warning, (png_const_structrp png_ptr, |
||
1999 | png_const_charp warning_message)); |
||
2000 | #endif |
||
2001 | |||
2002 | |||
2003 | /* Benign error in libpng. Can continue, but may have a problem. |
||
2004 | * User can choose whether to handle as a fatal error or as a warning. */ |
||
2005 | PNG_EXPORT(107, void, png_benign_error, (png_const_structrp png_ptr, |
||
2006 | png_const_charp warning_message)); |
||
2007 | |||
2008 | |||
2009 | /* Same, chunk name is prepended to message (only during read) */ |
||
2010 | PNG_EXPORT(108, void, png_chunk_benign_error, (png_const_structrp png_ptr, |
||
2011 | png_const_charp warning_message)); |
||
2012 | #endif |
||
2013 | |||
2014 | |||
2015 | (png_structrp png_ptr, int allowed)); |
||
2016 | #else |
||
2017 | # ifdef PNG_ALLOW_BENIGN_ERRORS |
||
2018 | # define png_benign_error png_warning |
||
2019 | # define png_chunk_benign_error png_chunk_warning |
||
2020 | # else |
||
2021 | # define png_benign_error png_error |
||
2022 | # define png_chunk_benign_error png_chunk_error |
||
2023 | # endif |
||
2024 | #endif |
||
2025 | |||
2026 | |||
2027 | * Similarly, the png_get_ |
||
2028 | * png_info_struct, either storing the parameters in the passed variables, or |
||
2029 | * setting pointers into the png_info_struct where the data is stored. The |
||
2030 | * png_get_ |
||
2031 | * in info_ptr, or return zero and do not change any of the parameters if the |
||
2032 | * data was not available. |
||
2033 | * |
||
2034 | * These functions should be used instead of directly accessing png_info |
||
2035 | * to avoid problems with future changes in the size and internal layout of |
||
2036 | * png_info_struct. |
||
2037 | */ |
||
2038 | /* Returns "flag" if chunk data is valid in info_ptr. */ |
||
2039 | PNG_EXPORT(110, png_uint_32, png_get_valid, (png_const_structrp png_ptr, |
||
2040 | png_const_inforp info_ptr, png_uint_32 flag)); |
||
2041 | |||
2042 | |||
2043 | PNG_EXPORT(111, png_size_t, png_get_rowbytes, (png_const_structrp png_ptr, |
||
2044 | png_const_inforp info_ptr)); |
||
2045 | |||
2046 | |||
2047 | /* Returns row_pointers, which is an array of pointers to scanlines that was |
||
2048 | * returned from png_read_png(). |
||
2049 | */ |
||
2050 | PNG_EXPORT(112, png_bytepp, png_get_rows, (png_const_structrp png_ptr, |
||
2051 | png_const_inforp info_ptr)); |
||
2052 | |||
2053 | |||
2054 | * by png_write_png(). |
||
2055 | */ |
||
2056 | PNG_EXPORT(113, void, png_set_rows, (png_const_structrp png_ptr, |
||
2057 | png_inforp info_ptr, png_bytepp row_pointers)); |
||
2058 | #endif |
||
2059 | |||
2060 | |||
2061 | PNG_EXPORT(114, png_byte, png_get_channels, (png_const_structrp png_ptr, |
||
2062 | png_const_inforp info_ptr)); |
||
2063 | |||
2064 | |||
2065 | /* Returns image width in pixels. */ |
||
2066 | PNG_EXPORT(115, png_uint_32, png_get_image_width, (png_const_structrp png_ptr, |
||
2067 | png_const_inforp info_ptr)); |
||
2068 | |||
2069 | |||
2070 | PNG_EXPORT(116, png_uint_32, png_get_image_height, (png_const_structrp png_ptr, |
||
2071 | png_const_inforp info_ptr)); |
||
2072 | |||
2073 | |||
2074 | PNG_EXPORT(117, png_byte, png_get_bit_depth, (png_const_structrp png_ptr, |
||
2075 | png_const_inforp info_ptr)); |
||
2076 | |||
2077 | |||
2078 | PNG_EXPORT(118, png_byte, png_get_color_type, (png_const_structrp png_ptr, |
||
2079 | png_const_inforp info_ptr)); |
||
2080 | |||
2081 | |||
2082 | PNG_EXPORT(119, png_byte, png_get_filter_type, (png_const_structrp png_ptr, |
||
2083 | png_const_inforp info_ptr)); |
||
2084 | |||
2085 | |||
2086 | PNG_EXPORT(120, png_byte, png_get_interlace_type, (png_const_structrp png_ptr, |
||
2087 | png_const_inforp info_ptr)); |
||
2088 | |||
2089 | |||
2090 | PNG_EXPORT(121, png_byte, png_get_compression_type, (png_const_structrp png_ptr, |
||
2091 | png_const_inforp info_ptr)); |
||
2092 | |||
2093 | |||
2094 | PNG_EXPORT(122, png_uint_32, png_get_pixels_per_meter, |
||
2095 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
||
2096 | PNG_EXPORT(123, png_uint_32, png_get_x_pixels_per_meter, |
||
2097 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
||
2098 | PNG_EXPORT(124, png_uint_32, png_get_y_pixels_per_meter, |
||
2099 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
||
2100 | |||
2101 | |||
2102 | PNG_FP_EXPORT(125, float, png_get_pixel_aspect_ratio, |
||
2103 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
||
2104 | PNG_FIXED_EXPORT(210, png_fixed_point, png_get_pixel_aspect_ratio_fixed, |
||
2105 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
||
2106 | |||
2107 | |||
2108 | PNG_EXPORT(126, png_int_32, png_get_x_offset_pixels, |
||
2109 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
||
2110 | PNG_EXPORT(127, png_int_32, png_get_y_offset_pixels, |
||
2111 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
||
2112 | PNG_EXPORT(128, png_int_32, png_get_x_offset_microns, |
||
2113 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
||
2114 | PNG_EXPORT(129, png_int_32, png_get_y_offset_microns, |
||
2115 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
||
2116 | |||
2117 | |||
2118 | |||
2119 | |||
2120 | /* Returns pointer to signature string read from PNG header */ |
||
2121 | PNG_EXPORT(130, png_const_bytep, png_get_signature, (png_const_structrp png_ptr, |
||
2122 | png_const_inforp info_ptr)); |
||
2123 | #endif |
||
2124 | |||
2125 | |||
2126 | PNG_EXPORT(131, png_uint_32, png_get_bKGD, (png_const_structrp png_ptr, |
||
2127 | png_inforp info_ptr, png_color_16p *background)); |
||
2128 | #endif |
||
2129 | |||
2130 | |||
2131 | PNG_EXPORT(132, void, png_set_bKGD, (png_const_structrp png_ptr, |
||
2132 | png_inforp info_ptr, png_const_color_16p background)); |
||
2133 | #endif |
||
2134 | |||
2135 | |||
2136 | PNG_FP_EXPORT(133, png_uint_32, png_get_cHRM, (png_const_structrp png_ptr, |
||
2137 | png_const_inforp info_ptr, double *white_x, double *white_y, double *red_x, |
||
2138 | double *red_y, double *green_x, double *green_y, double *blue_x, |
||
2139 | double *blue_y)) |
||
2140 | PNG_FP_EXPORT(230, png_uint_32, png_get_cHRM_XYZ, (png_const_structrp png_ptr, |
||
2141 | png_const_inforp info_ptr, double *red_X, double *red_Y, double *red_Z, |
||
2142 | double *green_X, double *green_Y, double *green_Z, double *blue_X, |
||
2143 | double *blue_Y, double *blue_Z)) |
||
2144 | PNG_FIXED_EXPORT(134, png_uint_32, png_get_cHRM_fixed, |
||
2145 | (png_const_structrp png_ptr, png_const_inforp info_ptr, |
||
2146 | png_fixed_point *int_white_x, png_fixed_point *int_white_y, |
||
2147 | png_fixed_point *int_red_x, png_fixed_point *int_red_y, |
||
2148 | png_fixed_point *int_green_x, png_fixed_point *int_green_y, |
||
2149 | png_fixed_point *int_blue_x, png_fixed_point *int_blue_y)) |
||
2150 | PNG_FIXED_EXPORT(231, png_uint_32, png_get_cHRM_XYZ_fixed, |
||
2151 | (png_const_structrp png_ptr, png_const_inforp info_ptr, |
||
2152 | png_fixed_point *int_red_X, png_fixed_point *int_red_Y, |
||
2153 | png_fixed_point *int_red_Z, png_fixed_point *int_green_X, |
||
2154 | png_fixed_point *int_green_Y, png_fixed_point *int_green_Z, |
||
2155 | png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y, |
||
2156 | png_fixed_point *int_blue_Z)) |
||
2157 | #endif |
||
2158 | |||
2159 | |||
2160 | PNG_FP_EXPORT(135, void, png_set_cHRM, (png_const_structrp png_ptr, |
||
2161 | png_inforp info_ptr, |
||
2162 | double white_x, double white_y, double red_x, double red_y, double green_x, |
||
2163 | double green_y, double blue_x, double blue_y)) |
||
2164 | PNG_FP_EXPORT(232, void, png_set_cHRM_XYZ, (png_const_structrp png_ptr, |
||
2165 | png_inforp info_ptr, double red_X, double red_Y, double red_Z, |
||
2166 | double green_X, double green_Y, double green_Z, double blue_X, |
||
2167 | double blue_Y, double blue_Z)) |
||
2168 | PNG_FIXED_EXPORT(136, void, png_set_cHRM_fixed, (png_const_structrp png_ptr, |
||
2169 | png_inforp info_ptr, png_fixed_point int_white_x, |
||
2170 | png_fixed_point int_white_y, png_fixed_point int_red_x, |
||
2171 | png_fixed_point int_red_y, png_fixed_point int_green_x, |
||
2172 | png_fixed_point int_green_y, png_fixed_point int_blue_x, |
||
2173 | png_fixed_point int_blue_y)) |
||
2174 | PNG_FIXED_EXPORT(233, void, png_set_cHRM_XYZ_fixed, (png_const_structrp png_ptr, |
||
2175 | png_inforp info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y, |
||
2176 | png_fixed_point int_red_Z, png_fixed_point int_green_X, |
||
2177 | png_fixed_point int_green_Y, png_fixed_point int_green_Z, |
||
2178 | png_fixed_point int_blue_X, png_fixed_point int_blue_Y, |
||
2179 | png_fixed_point int_blue_Z)) |
||
2180 | #endif |
||
2181 | |||
2182 | |||
2183 | PNG_FP_EXPORT(137, png_uint_32, png_get_gAMA, (png_const_structrp png_ptr, |
||
2184 | png_const_inforp info_ptr, double *file_gamma)) |
||
2185 | PNG_FIXED_EXPORT(138, png_uint_32, png_get_gAMA_fixed, |
||
2186 | (png_const_structrp png_ptr, png_const_inforp info_ptr, |
||
2187 | png_fixed_point *int_file_gamma)) |
||
2188 | #endif |
||
2189 | |||
2190 | |||
2191 | PNG_FP_EXPORT(139, void, png_set_gAMA, (png_const_structrp png_ptr, |
||
2192 | png_inforp info_ptr, double file_gamma)) |
||
2193 | PNG_FIXED_EXPORT(140, void, png_set_gAMA_fixed, (png_const_structrp png_ptr, |
||
2194 | png_inforp info_ptr, png_fixed_point int_file_gamma)) |
||
2195 | #endif |
||
2196 | |||
2197 | |||
2198 | PNG_EXPORT(141, png_uint_32, png_get_hIST, (png_const_structrp png_ptr, |
||
2199 | png_inforp info_ptr, png_uint_16p *hist)); |
||
2200 | #endif |
||
2201 | |||
2202 | |||
2203 | PNG_EXPORT(142, void, png_set_hIST, (png_const_structrp png_ptr, |
||
2204 | png_inforp info_ptr, png_const_uint_16p hist)); |
||
2205 | #endif |
||
2206 | |||
2207 | |||
2208 | png_const_inforp info_ptr, png_uint_32 *width, png_uint_32 *height, |
||
2209 | int *bit_depth, int *color_type, int *interlace_method, |
||
2210 | int *compression_method, int *filter_method)); |
||
2211 | |||
2212 | |||
2213 | png_inforp info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth, |
||
2214 | int color_type, int interlace_method, int compression_method, |
||
2215 | int filter_method)); |
||
2216 | |||
2217 | |||
2218 | PNG_EXPORT(145, png_uint_32, png_get_oFFs, (png_const_structrp png_ptr, |
||
2219 | png_const_inforp info_ptr, png_int_32 *offset_x, png_int_32 *offset_y, |
||
2220 | int *unit_type)); |
||
2221 | #endif |
||
2222 | |||
2223 | |||
2224 | PNG_EXPORT(146, void, png_set_oFFs, (png_const_structrp png_ptr, |
||
2225 | png_inforp info_ptr, png_int_32 offset_x, png_int_32 offset_y, |
||
2226 | int unit_type)); |
||
2227 | #endif |
||
2228 | |||
2229 | |||
2230 | PNG_EXPORT(147, png_uint_32, png_get_pCAL, (png_const_structrp png_ptr, |
||
2231 | png_inforp info_ptr, png_charp *purpose, png_int_32 *X0, |
||
2232 | png_int_32 *X1, int *type, int *nparams, png_charp *units, |
||
2233 | png_charpp *params)); |
||
2234 | #endif |
||
2235 | |||
2236 | |||
2237 | PNG_EXPORT(148, void, png_set_pCAL, (png_const_structrp png_ptr, |
||
2238 | png_inforp info_ptr, png_const_charp purpose, png_int_32 X0, png_int_32 X1, |
||
2239 | int type, int nparams, png_const_charp units, png_charpp params)); |
||
2240 | #endif |
||
2241 | |||
2242 | |||
2243 | PNG_EXPORT(149, png_uint_32, png_get_pHYs, (png_const_structrp png_ptr, |
||
2244 | png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, |
||
2245 | int *unit_type)); |
||
2246 | #endif |
||
2247 | |||
2248 | |||
2249 | PNG_EXPORT(150, void, png_set_pHYs, (png_const_structrp png_ptr, |
||
2250 | png_inforp info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type)); |
||
2251 | #endif |
||
2252 | |||
2253 | |||
2254 | png_inforp info_ptr, png_colorp *palette, int *num_palette)); |
||
2255 | |||
2256 | |||
2257 | png_inforp info_ptr, png_const_colorp palette, int num_palette)); |
||
2258 | |||
2259 | |||
2260 | PNG_EXPORT(153, png_uint_32, png_get_sBIT, (png_const_structrp png_ptr, |
||
2261 | png_inforp info_ptr, png_color_8p *sig_bit)); |
||
2262 | #endif |
||
2263 | |||
2264 | |||
2265 | PNG_EXPORT(154, void, png_set_sBIT, (png_const_structrp png_ptr, |
||
2266 | png_inforp info_ptr, png_const_color_8p sig_bit)); |
||
2267 | #endif |
||
2268 | |||
2269 | |||
2270 | PNG_EXPORT(155, png_uint_32, png_get_sRGB, (png_const_structrp png_ptr, |
||
2271 | png_const_inforp info_ptr, int *file_srgb_intent)); |
||
2272 | #endif |
||
2273 | |||
2274 | |||
2275 | PNG_EXPORT(156, void, png_set_sRGB, (png_const_structrp png_ptr, |
||
2276 | png_inforp info_ptr, int srgb_intent)); |
||
2277 | PNG_EXPORT(157, void, png_set_sRGB_gAMA_and_cHRM, (png_const_structrp png_ptr, |
||
2278 | png_inforp info_ptr, int srgb_intent)); |
||
2279 | #endif |
||
2280 | |||
2281 | |||
2282 | PNG_EXPORT(158, png_uint_32, png_get_iCCP, (png_const_structrp png_ptr, |
||
2283 | png_inforp info_ptr, png_charpp name, int *compression_type, |
||
2284 | png_bytepp profile, png_uint_32 *proflen)); |
||
2285 | #endif |
||
2286 | |||
2287 | |||
2288 | PNG_EXPORT(159, void, png_set_iCCP, (png_const_structrp png_ptr, |
||
2289 | png_inforp info_ptr, png_const_charp name, int compression_type, |
||
2290 | png_const_bytep profile, png_uint_32 proflen)); |
||
2291 | #endif |
||
2292 | |||
2293 | |||
2294 | PNG_EXPORT(160, int, png_get_sPLT, (png_const_structrp png_ptr, |
||
2295 | png_inforp info_ptr, png_sPLT_tpp entries)); |
||
2296 | #endif |
||
2297 | |||
2298 | |||
2299 | PNG_EXPORT(161, void, png_set_sPLT, (png_const_structrp png_ptr, |
||
2300 | png_inforp info_ptr, png_const_sPLT_tp entries, int nentries)); |
||
2301 | #endif |
||
2302 | |||
2303 | |||
2304 | /* png_get_text also returns the number of text chunks in *num_text */ |
||
2305 | PNG_EXPORT(162, int, png_get_text, (png_const_structrp png_ptr, |
||
2306 | png_inforp info_ptr, png_textp *text_ptr, int *num_text)); |
||
2307 | #endif |
||
2308 | |||
2309 | |||
2310 | * language, and translated keywords are NULL pointers, the structure |
||
2311 | * returned by png_get_text will always contain regular |
||
2312 | * zero-terminated C strings. They might be empty strings but |
||
2313 | * they will never be NULL pointers. |
||
2314 | */ |
||
2315 | |||
2316 | |||
2317 | PNG_EXPORT(163, void, png_set_text, (png_const_structrp png_ptr, |
||
2318 | png_inforp info_ptr, png_const_textp text_ptr, int num_text)); |
||
2319 | #endif |
||
2320 | |||
2321 | |||
2322 | PNG_EXPORT(164, png_uint_32, png_get_tIME, (png_const_structrp png_ptr, |
||
2323 | png_inforp info_ptr, png_timep *mod_time)); |
||
2324 | #endif |
||
2325 | |||
2326 | |||
2327 | PNG_EXPORT(165, void, png_set_tIME, (png_const_structrp png_ptr, |
||
2328 | png_inforp info_ptr, png_const_timep mod_time)); |
||
2329 | #endif |
||
2330 | |||
2331 | |||
2332 | PNG_EXPORT(166, png_uint_32, png_get_tRNS, (png_const_structrp png_ptr, |
||
2333 | png_inforp info_ptr, png_bytep *trans_alpha, int *num_trans, |
||
2334 | png_color_16p *trans_color)); |
||
2335 | #endif |
||
2336 | |||
2337 | |||
2338 | PNG_EXPORT(167, void, png_set_tRNS, (png_structrp png_ptr, |
||
2339 | png_inforp info_ptr, png_const_bytep trans_alpha, int num_trans, |
||
2340 | png_const_color_16p trans_color)); |
||
2341 | #endif |
||
2342 | |||
2343 | |||
2344 | PNG_FP_EXPORT(168, png_uint_32, png_get_sCAL, (png_const_structrp png_ptr, |
||
2345 | png_const_inforp info_ptr, int *unit, double *width, double *height)) |
||
2346 | #if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) || \ |
||
2347 | defined(PNG_FLOATING_POINT_SUPPORTED) |
||
2348 | /* NOTE: this API is currently implemented using floating point arithmetic, |
||
2349 | * consequently it can only be used on systems with floating point support. |
||
2350 | * In any case the range of values supported by png_fixed_point is small and it |
||
2351 | * is highly recommended that png_get_sCAL_s be used instead. |
||
2352 | */ |
||
2353 | PNG_FIXED_EXPORT(214, png_uint_32, png_get_sCAL_fixed, |
||
2354 | (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit, |
||
2355 | png_fixed_point *width, png_fixed_point *height)) |
||
2356 | #endif |
||
2357 | PNG_EXPORT(169, png_uint_32, png_get_sCAL_s, |
||
2358 | (png_const_structrp png_ptr, png_const_inforp info_ptr, int *unit, |
||
2359 | png_charpp swidth, png_charpp sheight)); |
||
2360 | |||
2361 | |||
2362 | png_inforp info_ptr, int unit, double width, double height)) |
||
2363 | PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_const_structrp png_ptr, |
||
2364 | png_inforp info_ptr, int unit, png_fixed_point width, |
||
2365 | png_fixed_point height)) |
||
2366 | PNG_EXPORT(171, void, png_set_sCAL_s, (png_const_structrp png_ptr, |
||
2367 | png_inforp info_ptr, int unit, |
||
2368 | png_const_charp swidth, png_const_charp sheight)); |
||
2369 | #endif /* PNG_sCAL_SUPPORTED */ |
||
2370 | |||
2371 | |||
2372 | /* Provide the default handling for all unknown chunks or, optionally, for |
||
2373 | * specific unknown chunks. |
||
2374 | * |
||
2375 | * NOTE: prior to 1.6.0 the handling specified for particular chunks on read was |
||
2376 | * ignored and the default was used, the per-chunk setting only had an effect on |
||
2377 | * write. If you wish to have chunk-specific handling on read in code that must |
||
2378 | * work on earlier versions you must use a user chunk callback to specify the |
||
2379 | * desired handling (keep or discard.) |
||
2380 | * |
||
2381 | * The 'keep' parameter is a PNG_HANDLE_CHUNK_ value as listed below. The |
||
2382 | * parameter is interpreted as follows: |
||
2383 | * |
||
2384 | * READ: |
||
2385 | * PNG_HANDLE_CHUNK_AS_DEFAULT: |
||
2386 | * Known chunks: do normal libpng processing, do not keep the chunk (but |
||
2387 | * see the comments below about PNG_HANDLE_AS_UNKNOWN_SUPPORTED) |
||
2388 | * Unknown chunks: for a specific chunk use the global default, when used |
||
2389 | * as the default discard the chunk data. |
||
2390 | * PNG_HANDLE_CHUNK_NEVER: |
||
2391 | * Discard the chunk data. |
||
2392 | * PNG_HANDLE_CHUNK_IF_SAFE: |
||
2393 | * Keep the chunk data if the chunk is not critical else raise a chunk |
||
2394 | * error. |
||
2395 | * PNG_HANDLE_CHUNK_ALWAYS: |
||
2396 | * Keep the chunk data. |
||
2397 | * |
||
2398 | * If the chunk data is saved it can be retrieved using png_get_unknown_chunks, |
||
2399 | * below. Notice that specifying "AS_DEFAULT" as a global default is equivalent |
||
2400 | * to specifying "NEVER", however when "AS_DEFAULT" is used for specific chunks |
||
2401 | * it simply resets the behavior to the libpng default. |
||
2402 | * |
||
2403 | * INTERACTION WTIH USER CHUNK CALLBACKS: |
||
2404 | * The per-chunk handling is always used when there is a png_user_chunk_ptr |
||
2405 | * callback and the callback returns 0; the chunk is then always stored *unless* |
||
2406 | * it is critical and the per-chunk setting is other than ALWAYS. Notice that |
||
2407 | * the global default is *not* used in this case. (In effect the per-chunk |
||
2408 | * value is incremented to at least IF_SAFE.) |
||
2409 | * |
||
2410 | * IMPORTANT NOTE: this behavior will change in libpng 1.7 - the global and |
||
2411 | * per-chunk defaults will be honored. If you want to preserve the current |
||
2412 | * behavior when your callback returns 0 you must set PNG_HANDLE_CHUNK_IF_SAFE |
||
2413 | * as the default - if you don't do this libpng 1.6 will issue a warning. |
||
2414 | * |
||
2415 | * If you want unhandled unknown chunks to be discarded in libpng 1.6 and |
||
2416 | * earlier simply return '1' (handled). |
||
2417 | * |
||
2418 | * PNG_HANDLE_AS_UNKNOWN_SUPPORTED: |
||
2419 | * If this is *not* set known chunks will always be handled by libpng and |
||
2420 | * will never be stored in the unknown chunk list. Known chunks listed to |
||
2421 | * png_set_keep_unknown_chunks will have no effect. If it is set then known |
||
2422 | * chunks listed with a keep other than AS_DEFAULT will *never* be processed |
||
2423 | * by libpng, in addition critical chunks must either be processed by the |
||
2424 | * callback or saved. |
||
2425 | * |
||
2426 | * The IHDR and IEND chunks must not be listed. Because this turns off the |
||
2427 | * default handling for chunks that would otherwise be recognized the |
||
2428 | * behavior of libpng transformations may well become incorrect! |
||
2429 | * |
||
2430 | * WRITE: |
||
2431 | * When writing chunks the options only apply to the chunks specified by |
||
2432 | * png_set_unknown_chunks (below), libpng will *always* write known chunks |
||
2433 | * required by png_set_ calls and will always write the core critical chunks |
||
2434 | * (as required for PLTE). |
||
2435 | * |
||
2436 | * Each chunk in the png_set_unknown_chunks list is looked up in the |
||
2437 | * png_set_keep_unknown_chunks list to find the keep setting, this is then |
||
2438 | * interpreted as follows: |
||
2439 | * |
||
2440 | * PNG_HANDLE_CHUNK_AS_DEFAULT: |
||
2441 | * Write safe-to-copy chunks and write other chunks if the global |
||
2442 | * default is set to _ALWAYS, otherwise don't write this chunk. |
||
2443 | * PNG_HANDLE_CHUNK_NEVER: |
||
2444 | * Do not write the chunk. |
||
2445 | * PNG_HANDLE_CHUNK_IF_SAFE: |
||
2446 | * Write the chunk if it is safe-to-copy, otherwise do not write it. |
||
2447 | * PNG_HANDLE_CHUNK_ALWAYS: |
||
2448 | * Write the chunk. |
||
2449 | * |
||
2450 | * Note that the default behavior is effectively the opposite of the read case - |
||
2451 | * in read unknown chunks are not stored by default, in write they are written |
||
2452 | * by default. Also the behavior of PNG_HANDLE_CHUNK_IF_SAFE is very different |
||
2453 | * - on write the safe-to-copy bit is checked, on read the critical bit is |
||
2454 | * checked and on read if the chunk is critical an error will be raised. |
||
2455 | * |
||
2456 | * num_chunks: |
||
2457 | * =========== |
||
2458 | * If num_chunks is positive, then the "keep" parameter specifies the manner |
||
2459 | * for handling only those chunks appearing in the chunk_list array, |
||
2460 | * otherwise the chunk list array is ignored. |
||
2461 | * |
||
2462 | * If num_chunks is 0 the "keep" parameter specifies the default behavior for |
||
2463 | * unknown chunks, as described above. |
||
2464 | * |
||
2465 | * If num_chunks is negative, then the "keep" parameter specifies the manner |
||
2466 | * for handling all unknown chunks plus all chunks recognized by libpng |
||
2467 | * except for the IHDR, PLTE, tRNS, IDAT, and IEND chunks (which continue to |
||
2468 | * be processed by libpng. |
||
2469 | */ |
||
2470 | PNG_EXPORT(172, void, png_set_keep_unknown_chunks, (png_structrp png_ptr, |
||
2471 | int keep, png_const_bytep chunk_list, int num_chunks)); |
||
2472 | |||
2473 | |||
2474 | * the result is therefore true (non-zero) if special handling is required, |
||
2475 | * false for the default handling. |
||
2476 | */ |
||
2477 | PNG_EXPORT(173, int, png_handle_as_unknown, (png_const_structrp png_ptr, |
||
2478 | png_const_bytep chunk_name)); |
||
2479 | #endif |
||
2480 | |||
2481 | |||
2482 | PNG_EXPORT(174, void, png_set_unknown_chunks, (png_const_structrp png_ptr, |
||
2483 | png_inforp info_ptr, png_const_unknown_chunkp unknowns, |
||
2484 | int num_unknowns)); |
||
2485 | /* NOTE: prior to 1.6.0 this routine set the 'location' field of the added |
||
2486 | * unknowns to the location currently stored in the png_struct. This is |
||
2487 | * invariably the wrong value on write. To fix this call the following API |
||
2488 | * for each chunk in the list with the correct location. If you know your |
||
2489 | * code won't be compiled on earlier versions you can rely on |
||
2490 | * png_set_unknown_chunks(write-ptr, png_get_unknown_chunks(read-ptr)) doing |
||
2491 | * the correct thing. |
||
2492 | */ |
||
2493 | |||
2494 | |||
2495 | (png_const_structrp png_ptr, png_inforp info_ptr, int chunk, int location)); |
||
2496 | |||
2497 | |||
2498 | png_inforp info_ptr, png_unknown_chunkpp entries)); |
||
2499 | #endif |
||
2500 | |||
2501 | |||
2502 | * If you need to turn it off for a chunk that your application has freed, |
||
2503 | * you can use png_set_invalid(png_ptr, info_ptr, PNG_INFO_CHNK); |
||
2504 | */ |
||
2505 | PNG_EXPORT(177, void, png_set_invalid, (png_const_structrp png_ptr, |
||
2506 | png_inforp info_ptr, int mask)); |
||
2507 | |||
2508 | |||
2509 | /* The "params" pointer is currently not used and is for future expansion. */ |
||
2510 | PNG_EXPORT(178, void, png_read_png, (png_structrp png_ptr, png_inforp info_ptr, |
||
2511 | int transforms, png_voidp params)); |
||
2512 | PNG_EXPORT(179, void, png_write_png, (png_structrp png_ptr, png_inforp info_ptr, |
||
2513 | int transforms, png_voidp params)); |
||
2514 | #endif |
||
2515 | |||
2516 | |||
2517 | (png_const_structrp png_ptr)); |
||
2518 | PNG_EXPORT(181, png_const_charp, png_get_header_ver, |
||
2519 | (png_const_structrp png_ptr)); |
||
2520 | PNG_EXPORT(182, png_const_charp, png_get_header_version, |
||
2521 | (png_const_structrp png_ptr)); |
||
2522 | PNG_EXPORT(183, png_const_charp, png_get_libpng_ver, |
||
2523 | (png_const_structrp png_ptr)); |
||
2524 | |||
2525 | |||
2526 | PNG_EXPORT(184, png_uint_32, png_permit_mng_features, (png_structrp png_ptr, |
||
2527 | png_uint_32 mng_features_permitted)); |
||
2528 | #endif |
||
2529 | |||
2530 | |||
2531 | #define PNG_HANDLE_CHUNK_AS_DEFAULT 0 |
||
2532 | #define PNG_HANDLE_CHUNK_NEVER 1 |
||
2533 | #define PNG_HANDLE_CHUNK_IF_SAFE 2 |
||
2534 | #define PNG_HANDLE_CHUNK_ALWAYS 3 |
||
2535 | #define PNG_HANDLE_CHUNK_LAST 4 |
||
2536 | |||
2537 | |||
2538 | * messages before passing them to the error or warning handler. |
||
2539 | */ |
||
2540 | #ifdef PNG_ERROR_NUMBERS_SUPPORTED |
||
2541 | PNG_EXPORT(185, void, png_set_strip_error_numbers, (png_structrp png_ptr, |
||
2542 | png_uint_32 strip_mode)); |
||
2543 | #endif |
||
2544 | |||
2545 | |||
2546 | #ifdef PNG_SET_USER_LIMITS_SUPPORTED |
||
2547 | PNG_EXPORT(186, void, png_set_user_limits, (png_structrp png_ptr, |
||
2548 | png_uint_32 user_width_max, png_uint_32 user_height_max)); |
||
2549 | PNG_EXPORT(187, png_uint_32, png_get_user_width_max, |
||
2550 | (png_const_structrp png_ptr)); |
||
2551 | PNG_EXPORT(188, png_uint_32, png_get_user_height_max, |
||
2552 | (png_const_structrp png_ptr)); |
||
2553 | /* Added in libpng-1.4.0 */ |
||
2554 | PNG_EXPORT(189, void, png_set_chunk_cache_max, (png_structrp png_ptr, |
||
2555 | png_uint_32 user_chunk_cache_max)); |
||
2556 | PNG_EXPORT(190, png_uint_32, png_get_chunk_cache_max, |
||
2557 | (png_const_structrp png_ptr)); |
||
2558 | /* Added in libpng-1.4.1 */ |
||
2559 | PNG_EXPORT(191, void, png_set_chunk_malloc_max, (png_structrp png_ptr, |
||
2560 | png_alloc_size_t user_chunk_cache_max)); |
||
2561 | PNG_EXPORT(192, png_alloc_size_t, png_get_chunk_malloc_max, |
||
2562 | (png_const_structrp png_ptr)); |
||
2563 | #endif |
||
2564 | |||
2565 | |||
2566 | PNG_EXPORT(193, png_uint_32, png_get_pixels_per_inch, |
||
2567 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
||
2568 | |||
2569 | |||
2570 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
||
2571 | |||
2572 | |||
2573 | (png_const_structrp png_ptr, png_const_inforp info_ptr)); |
||
2574 | |||
2575 | |||
2576 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
||
2577 | #ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ |
||
2578 | PNG_FIXED_EXPORT(211, png_fixed_point, png_get_x_offset_inches_fixed, |
||
2579 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
||
2580 | #endif |
||
2581 | |||
2582 | |||
2583 | png_const_inforp info_ptr)) |
||
2584 | #ifdef PNG_FIXED_POINT_SUPPORTED /* otherwise not implemented. */ |
||
2585 | PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed, |
||
2586 | (png_const_structrp png_ptr, png_const_inforp info_ptr)) |
||
2587 | #endif |
||
2588 | |||
2589 | |||
2590 | PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structrp png_ptr, |
||
2591 | png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y, |
||
2592 | int *unit_type)); |
||
2593 | # endif /* PNG_pHYs_SUPPORTED */ |
||
2594 | #endif /* PNG_INCH_CONVERSIONS_SUPPORTED */ |
||
2595 | |||
2596 | |||
2597 | #ifdef PNG_IO_STATE_SUPPORTED |
||
2598 | PNG_EXPORT(199, png_uint_32, png_get_io_state, (png_const_structrp png_ptr)); |
||
2599 | |||
2600 | |||
2601 | PNG_REMOVED(200, png_const_bytep, png_get_io_chunk_name, (png_structrp png_ptr), |
||
2602 | PNG_DEPRECATED) |
||
2603 | |||
2604 | |||
2605 | (png_const_structrp png_ptr)); |
||
2606 | |||
2607 | |||
2608 | # define PNG_IO_NONE 0x0000 /* no I/O at this moment */ |
||
2609 | # define PNG_IO_READING 0x0001 /* currently reading */ |
||
2610 | # define PNG_IO_WRITING 0x0002 /* currently writing */ |
||
2611 | # define PNG_IO_SIGNATURE 0x0010 /* currently at the file signature */ |
||
2612 | # define PNG_IO_CHUNK_HDR 0x0020 /* currently at the chunk header */ |
||
2613 | # define PNG_IO_CHUNK_DATA 0x0040 /* currently at the chunk data */ |
||
2614 | # define PNG_IO_CHUNK_CRC 0x0080 /* currently at the chunk crc */ |
||
2615 | # define PNG_IO_MASK_OP 0x000f /* current operation: reading/writing */ |
||
2616 | # define PNG_IO_MASK_LOC 0x00f0 /* current location: sig/hdr/data/crc */ |
||
2617 | #endif /* ?PNG_IO_STATE_SUPPORTED */ |
||
2618 | |||
2619 | |||
2620 | * libpng interlace handling is turned off the macros may be used to handle |
||
2621 | * interlaced images within the application. |
||
2622 | */ |
||
2623 | #define PNG_INTERLACE_ADAM7_PASSES 7 |
||
2624 | |||
2625 | |||
2626 | * full, image which appears in a given pass. 'pass' is in the range 0 |
||
2627 | * to 6 and the result is in the range 0 to 7. |
||
2628 | */ |
||
2629 | #define PNG_PASS_START_ROW(pass) (((1&~(pass))<<(3-((pass)>>1)))&7) |
||
2630 | #define PNG_PASS_START_COL(pass) (((1& (pass))<<(3-(((pass)+1)>>1)))&7) |
||
2631 | |||
2632 | |||
2633 | * pixels in the input - effectively the inverse of the 'COL_SHIFT' macro that |
||
2634 | * follows. Note that ROW_OFFSET is the offset from one row to the next whereas |
||
2635 | * COL_OFFSET is from one column to the next, within a row. |
||
2636 | */ |
||
2637 | #define PNG_PASS_ROW_OFFSET(pass) ((pass)>2?(8>>(((pass)-1)>>1)):8) |
||
2638 | #define PNG_PASS_COL_OFFSET(pass) (1<<((7-(pass))>>1)) |
||
2639 | |||
2640 | |||
2641 | * pass. This is expressed as a shift - effectively log2 of the number or |
||
2642 | * rows or columns in each 8x8 tile of the original image. |
||
2643 | */ |
||
2644 | #define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3) |
||
2645 | #define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3) |
||
2646 | |||
2647 | |||
2648 | * pass of an image given its height or width. In fact these macros may |
||
2649 | * return non-zero even though the sub-image is empty, because the other |
||
2650 | * dimension may be empty for a small image. |
||
2651 | */ |
||
2652 | #define PNG_PASS_ROWS(height, pass) (((height)+(((1< |
||
2653 | -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass)) |
||
2654 | #define PNG_PASS_COLS(width, pass) (((width)+(((1< |
||
2655 | -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass)) |
||
2656 | |||
2657 | |||
2658 | * necessary to find the row in the output image given a row in an interlaced |
||
2659 | * image, so two more macros: |
||
2660 | */ |
||
2661 | #define PNG_ROW_FROM_PASS_ROW(y_in, pass) \ |
||
2662 | (((y_in)< |
||
2663 | #define PNG_COL_FROM_PASS_COL(x_in, pass) \ |
||
2664 | (((x_in)< |
||
2665 | |||
2666 | |||
2667 | * or column is in a particular pass. These use a common utility macro that |
||
2668 | * returns a mask for a given pass - the offset 'off' selects the row or |
||
2669 | * column version. The mask has the appropriate bit set for each column in |
||
2670 | * the tile. |
||
2671 | */ |
||
2672 | #define PNG_PASS_MASK(pass,off) ( \ |
||
2673 | ((0x110145AF>>(((7-(off))-(pass))<<2)) & 0xF) | \ |
||
2674 | ((0x01145AF0>>(((7-(off))-(pass))<<2)) & 0xF0)) |
||
2675 | |||
2676 | |||
2677 | ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1) |
||
2678 | #define PNG_COL_IN_INTERLACE_PASS(x, pass) \ |
||
2679 | ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1) |
||
2680 | |||
2681 | |||
2682 | /* With these routines we avoid an integer divide, which will be slower on |
||
2683 | * most machines. However, it does take more operations than the corresponding |
||
2684 | * divide method, so it may be slower on a few RISC systems. There are two |
||
2685 | * shifts (by 8 or 16 bits) and an addition, versus a single integer divide. |
||
2686 | * |
||
2687 | * Note that the rounding factors are NOT supposed to be the same! 128 and |
||
2688 | * 32768 are correct for the NODIV code; 127 and 32767 are correct for the |
||
2689 | * standard method. |
||
2690 | * |
||
2691 | * [Optimized code by Greg Roelofs and Mark Adler...blame us for bugs. :-) ] |
||
2692 | */ |
||
2693 | |||
2694 | |||
2695 | |||
2696 | |||
2697 | { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \ |
||
2698 | * (png_uint_16)(alpha) \ |
||
2699 | + (png_uint_16)(bg)*(png_uint_16)(255 \ |
||
2700 | - (png_uint_16)(alpha)) + 128); \ |
||
2701 | (composite) = (png_byte)((temp + (temp >> 8)) >> 8); } |
||
2702 | |||
2703 | |||
2704 | { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) \ |
||
2705 | * (png_uint_32)(alpha) \ |
||
2706 | + (png_uint_32)(bg)*(65535 \ |
||
2707 | - (png_uint_32)(alpha)) + 32768); \ |
||
2708 | (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); } |
||
2709 | |||
2710 | |||
2711 | |||
2712 | |||
2713 | (composite) = (png_byte)(((png_uint_16)(fg) * (png_uint_16)(alpha) + \ |
||
2714 | (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \ |
||
2715 | 127) / 255) |
||
2716 | |||
2717 | |||
2718 | (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \ |
||
2719 | (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) + \ |
||
2720 | 32767) / 65535) |
||
2721 | #endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */ |
||
2722 | |||
2723 | |||
2724 | PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf)); |
||
2725 | PNG_EXPORT(202, png_uint_16, png_get_uint_16, (png_const_bytep buf)); |
||
2726 | PNG_EXPORT(203, png_int_32, png_get_int_32, (png_const_bytep buf)); |
||
2727 | #endif |
||
2728 | |||
2729 | |||
2730 | png_const_bytep buf)); |
||
2731 | /* No png_get_int_16 -- may be added if there's a real need for it. */ |
||
2732 | |||
2733 | |||
2734 | #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED |
||
2735 | PNG_EXPORT(205, void, png_save_uint_32, (png_bytep buf, png_uint_32 i)); |
||
2736 | #endif |
||
2737 | #ifdef PNG_SAVE_INT_32_SUPPORTED |
||
2738 | PNG_EXPORT(206, void, png_save_int_32, (png_bytep buf, png_int_32 i)); |
||
2739 | #endif |
||
2740 | |||
2741 | |||
2742 | * The parameter is declared unsigned int, not png_uint_16, |
||
2743 | * just to avoid potential problems on pre-ANSI C compilers. |
||
2744 | */ |
||
2745 | #ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED |
||
2746 | PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i)); |
||
2747 | /* No png_save_int_16 -- may be added if there's a real need for it. */ |
||
2748 | #endif |
||
2749 | |||
2750 | |||
2751 | /* Inline macros to do direct reads of bytes from the input buffer. |
||
2752 | * The png_get_int_32() routine assumes we are using two's complement |
||
2753 | * format for negative values, which is almost certainly true. |
||
2754 | */ |
||
2755 | # define PNG_get_uint_32(buf) \ |
||
2756 | (((png_uint_32)(*(buf)) << 24) + \ |
||
2757 | ((png_uint_32)(*((buf) + 1)) << 16) + \ |
||
2758 | ((png_uint_32)(*((buf) + 2)) << 8) + \ |
||
2759 | ((png_uint_32)(*((buf) + 3)))) |
||
2760 | |||
2761 | |||
2762 | * function) incorrectly returned a value of type png_uint_32. |
||
2763 | */ |
||
2764 | # define PNG_get_uint_16(buf) \ |
||
2765 | ((png_uint_16) \ |
||
2766 | (((unsigned int)(*(buf)) << 8) + \ |
||
2767 | ((unsigned int)(*((buf) + 1))))) |
||
2768 | |||
2769 | |||
2770 | ((png_int_32)((*(buf) & 0x80) \ |
||
2771 | ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffffL) + 1)) \ |
||
2772 | : (png_int_32)png_get_uint_32(buf))) |
||
2773 | |||
2774 | |||
2775 | * but defining a macro name prefixed with PNG_PREFIX. |
||
2776 | */ |
||
2777 | # ifndef PNG_PREFIX |
||
2778 | # define png_get_uint_32(buf) PNG_get_uint_32(buf) |
||
2779 | # define png_get_uint_16(buf) PNG_get_uint_16(buf) |
||
2780 | # define png_get_int_32(buf) PNG_get_int_32(buf) |
||
2781 | # endif |
||
2782 | #else |
||
2783 | # ifdef PNG_PREFIX |
||
2784 | /* No macros; revert to the (redefined) function */ |
||
2785 | # define PNG_get_uint_32 (png_get_uint_32) |
||
2786 | # define PNG_get_uint_16 (png_get_uint_16) |
||
2787 | # define PNG_get_int_32 (png_get_int_32) |
||
2788 | # endif |
||
2789 | #endif |
||
2790 | |||
2791 | |||
2792 | * SIMPLIFIED API |
||
2793 | ******************************************************************************* |
||
2794 | * |
||
2795 | * Please read the documentation in libpng-manual.txt (TODO: write said |
||
2796 | * documentation) if you don't understand what follows. |
||
2797 | * |
||
2798 | * The simplified API hides the details of both libpng and the PNG file format |
||
2799 | * itself. It allows PNG files to be read into a very limited number of |
||
2800 | * in-memory bitmap formats or to be written from the same formats. If these |
||
2801 | * formats do not accomodate your needs then you can, and should, use the more |
||
2802 | * sophisticated APIs above - these support a wide variety of in-memory formats |
||
2803 | * and a wide variety of sophisticated transformations to those formats as well |
||
2804 | * as a wide variety of APIs to manipulate ancillary information. |
||
2805 | * |
||
2806 | * To read a PNG file using the simplified API: |
||
2807 | * |
||
2808 | * 1) Declare a 'png_image' structure (see below) on the stack and set the |
||
2809 | * version field to PNG_IMAGE_VERSION. |
||
2810 | * 2) Call the appropriate png_image_begin_read... function. |
||
2811 | * 3) Set the png_image 'format' member to the required sample format. |
||
2812 | * 4) Allocate a buffer for the image and, if required, the color-map. |
||
2813 | * 5) Call png_image_finish_read to read the image and, if required, the |
||
2814 | * color-map into your buffers. |
||
2815 | * |
||
2816 | * There are no restrictions on the format of the PNG input itself; all valid |
||
2817 | * color types, bit depths, and interlace methods are acceptable, and the |
||
2818 | * input image is transformed as necessary to the requested in-memory format |
||
2819 | * during the png_image_finish_read() step. The only caveat is that if you |
||
2820 | * request a color-mapped image from a PNG that is full-color or makes |
||
2821 | * complex use of an alpha channel the transformation is extremely lossy and the |
||
2822 | * result may look terrible. |
||
2823 | * |
||
2824 | * To write a PNG file using the simplified API: |
||
2825 | * |
||
2826 | * 1) Declare a 'png_image' structure on the stack and memset() it to all zero. |
||
2827 | * 2) Initialize the members of the structure that describe the image, setting |
||
2828 | * the 'format' member to the format of the image samples. |
||
2829 | * 3) Call the appropriate png_image_write... function with a pointer to the |
||
2830 | * image and, if necessary, the color-map to write the PNG data. |
||
2831 | * |
||
2832 | * png_image is a structure that describes the in-memory format of an image |
||
2833 | * when it is being read or defines the in-memory format of an image that you |
||
2834 | * need to write: |
||
2835 | */ |
||
2836 | #define PNG_IMAGE_VERSION 1 |
||
2837 | |||
2838 | |||
2839 | typedef struct |
||
2840 | { |
||
2841 | png_controlp opaque; /* Initialize to NULL, free with png_image_free */ |
||
2842 | png_uint_32 version; /* Set to PNG_IMAGE_VERSION */ |
||
2843 | png_uint_32 width; /* Image width in pixels (columns) */ |
||
2844 | png_uint_32 height; /* Image height in pixels (rows) */ |
||
2845 | png_uint_32 format; /* Image format as defined below */ |
||
2846 | png_uint_32 flags; /* A bit mask containing informational flags */ |
||
2847 | png_uint_32 colormap_entries; |
||
2848 | /* Number of entries in the color-map */ |
||
2849 | |||
2850 | |||
2851 | * non-zero value and the 'message' field will contain a '\0' terminated |
||
2852 | * string with the libpng error or warning message. If both warnings and |
||
2853 | * an error were encountered, only the error is recorded. If there |
||
2854 | * are multiple warnings, only the first one is recorded. |
||
2855 | * |
||
2856 | * The upper 30 bits of this value are reserved, the low two bits contain |
||
2857 | * a value as follows: |
||
2858 | */ |
||
2859 | # define PNG_IMAGE_WARNING 1 |
||
2860 | # define PNG_IMAGE_ERROR 2 |
||
2861 | /* |
||
2862 | * The result is a two bit code such that a value more than 1 indicates |
||
2863 | * a failure in the API just called: |
||
2864 | * |
||
2865 | * 0 - no warning or error |
||
2866 | * 1 - warning |
||
2867 | * 2 - error |
||
2868 | * 3 - error preceded by warning |
||
2869 | */ |
||
2870 | # define PNG_IMAGE_FAILED(png_cntrl) ((((png_cntrl).warning_or_error)&0x03)>1) |
||
2871 | |||
2872 | |||
2873 | |||
2874 | |||
2875 | } png_image, *png_imagep; |
||
2876 | |||
2877 | |||
2878 | * original values in the range 0 to 1.0: |
||
2879 | * |
||
2880 | * 1: A single gray or luminance channel (G). |
||
2881 | * 2: A gray/luminance channel and an alpha channel (GA). |
||
2882 | * 3: Three red, green, blue color channels (RGB). |
||
2883 | * 4: Three color channels and an alpha channel (RGBA). |
||
2884 | * |
||
2885 | * The components are encoded in one of two ways: |
||
2886 | * |
||
2887 | * a) As a small integer, value 0..255, contained in a single byte. For the |
||
2888 | * alpha channel the original value is simply value/255. For the color or |
||
2889 | * luminance channels the value is encoded according to the sRGB specification |
||
2890 | * and matches the 8-bit format expected by typical display devices. |
||
2891 | * |
||
2892 | * The color/gray channels are not scaled (pre-multiplied) by the alpha |
||
2893 | * channel and are suitable for passing to color management software. |
||
2894 | * |
||
2895 | * b) As a value in the range 0..65535, contained in a 2-byte integer. All |
||
2896 | * channels can be converted to the original value by dividing by 65535; all |
||
2897 | * channels are linear. Color channels use the RGB encoding (RGB end-points) of |
||
2898 | * the sRGB specification. This encoding is identified by the |
||
2899 | * PNG_FORMAT_FLAG_LINEAR flag below. |
||
2900 | * |
||
2901 | * When the simplified API needs to convert between sRGB and linear colorspaces, |
||
2902 | * the actual sRGB transfer curve defined in the sRGB specification (see the |
||
2903 | * article at http://en.wikipedia.org/wiki/SRGB) is used, not the gamma=1/2.2 |
||
2904 | * approximation used elsewhere in libpng. |
||
2905 | * |
||
2906 | * When an alpha channel is present it is expected to denote pixel coverage |
||
2907 | * of the color or luminance channels and is returned as an associated alpha |
||
2908 | * channel: the color/gray channels are scaled (pre-multiplied) by the alpha |
||
2909 | * value. |
||
2910 | * |
||
2911 | * The samples are either contained directly in the image data, between 1 and 8 |
||
2912 | * bytes per pixel according to the encoding, or are held in a color-map indexed |
||
2913 | * by bytes in the image data. In the case of a color-map the color-map entries |
||
2914 | * are individual samples, encoded as above, and the image data has one byte per |
||
2915 | * pixel to select the relevant sample from the color-map. |
||
2916 | */ |
||
2917 | |||
2918 | |||
2919 | * |
||
2920 | * #defines to be used in png_image::format. Each #define identifies a |
||
2921 | * particular layout of sample data and, if present, alpha values. There are |
||
2922 | * separate defines for each of the two component encodings. |
||
2923 | * |
||
2924 | * A format is built up using single bit flag values. All combinations are |
||
2925 | * valid. Formats can be built up from the flag values or you can use one of |
||
2926 | * the predefined values below. When testing formats always use the FORMAT_FLAG |
||
2927 | * macros to test for individual features - future versions of the library may |
||
2928 | * add new flags. |
||
2929 | * |
||
2930 | * When reading or writing color-mapped images the format should be set to the |
||
2931 | * format of the entries in the color-map then png_image_{read,write}_colormap |
||
2932 | * called to read or write the color-map and set the format correctly for the |
||
2933 | * image data. Do not set the PNG_FORMAT_FLAG_COLORMAP bit directly! |
||
2934 | * |
||
2935 | * NOTE: libpng can be built with particular features disabled, if you see |
||
2936 | * compiler errors because the definition of one of the following flags has been |
||
2937 | * compiled out it is because libpng does not have the required support. It is |
||
2938 | * possible, however, for the libpng configuration to enable the format on just |
||
2939 | * read or just write; in that case you may see an error at run time. You can |
||
2940 | * guard against this by checking for the definition of the appropriate |
||
2941 | * "_SUPPORTED" macro, one of: |
||
2942 | * |
||
2943 | * PNG_SIMPLIFIED_{READ,WRITE}_{BGR,AFIRST}_SUPPORTED |
||
2944 | */ |
||
2945 | #define PNG_FORMAT_FLAG_ALPHA 0x01U /* format with an alpha channel */ |
||
2946 | #define PNG_FORMAT_FLAG_COLOR 0x02U /* color format: otherwise grayscale */ |
||
2947 | #define PNG_FORMAT_FLAG_LINEAR 0x04U /* 2 byte channels else 1 byte */ |
||
2948 | #define PNG_FORMAT_FLAG_COLORMAP 0x08U /* image data is color-mapped */ |
||
2949 | |||
2950 | |||
2951 | # define PNG_FORMAT_FLAG_BGR 0x10U /* BGR colors, else order is RGB */ |
||
2952 | #endif |
||
2953 | |||
2954 | |||
2955 | # define PNG_FORMAT_FLAG_AFIRST 0x20U /* alpha channel comes first */ |
||
2956 | #endif |
||
2957 | |||
2958 | |||
2959 | * |
||
2960 | * First the single byte (sRGB) formats: |
||
2961 | */ |
||
2962 | #define PNG_FORMAT_GRAY 0 |
||
2963 | #define PNG_FORMAT_GA PNG_FORMAT_FLAG_ALPHA |
||
2964 | #define PNG_FORMAT_AG (PNG_FORMAT_GA|PNG_FORMAT_FLAG_AFIRST) |
||
2965 | #define PNG_FORMAT_RGB PNG_FORMAT_FLAG_COLOR |
||
2966 | #define PNG_FORMAT_BGR (PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_BGR) |
||
2967 | #define PNG_FORMAT_RGBA (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_ALPHA) |
||
2968 | #define PNG_FORMAT_ARGB (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_AFIRST) |
||
2969 | #define PNG_FORMAT_BGRA (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_ALPHA) |
||
2970 | #define PNG_FORMAT_ABGR (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_AFIRST) |
||
2971 | |||
2972 | |||
2973 | * indicate a luminance (gray) channel. |
||
2974 | */ |
||
2975 | #define PNG_FORMAT_LINEAR_Y PNG_FORMAT_FLAG_LINEAR |
||
2976 | #define PNG_FORMAT_LINEAR_Y_ALPHA (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_ALPHA) |
||
2977 | #define PNG_FORMAT_LINEAR_RGB (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR) |
||
2978 | #define PNG_FORMAT_LINEAR_RGB_ALPHA \ |
||
2979 | (PNG_FORMAT_FLAG_LINEAR|PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA) |
||
2980 | |||
2981 | |||
2982 | * is an index into the color-map which is formatted as above. To obtain a |
||
2983 | * color-mapped format it is sufficient just to add the PNG_FOMAT_FLAG_COLORMAP |
||
2984 | * to one of the above definitions, or you can use one of the definitions below. |
||
2985 | */ |
||
2986 | #define PNG_FORMAT_RGB_COLORMAP (PNG_FORMAT_RGB|PNG_FORMAT_FLAG_COLORMAP) |
||
2987 | #define PNG_FORMAT_BGR_COLORMAP (PNG_FORMAT_BGR|PNG_FORMAT_FLAG_COLORMAP) |
||
2988 | #define PNG_FORMAT_RGBA_COLORMAP (PNG_FORMAT_RGBA|PNG_FORMAT_FLAG_COLORMAP) |
||
2989 | #define PNG_FORMAT_ARGB_COLORMAP (PNG_FORMAT_ARGB|PNG_FORMAT_FLAG_COLORMAP) |
||
2990 | #define PNG_FORMAT_BGRA_COLORMAP (PNG_FORMAT_BGRA|PNG_FORMAT_FLAG_COLORMAP) |
||
2991 | #define PNG_FORMAT_ABGR_COLORMAP (PNG_FORMAT_ABGR|PNG_FORMAT_FLAG_COLORMAP) |
||
2992 | |||
2993 | |||
2994 | * |
||
2995 | * These are convenience macros to derive information from a png_image |
||
2996 | * structure. The PNG_IMAGE_SAMPLE_ macros return values appropriate to the |
||
2997 | * actual image sample values - either the entries in the color-map or the |
||
2998 | * pixels in the image. The PNG_IMAGE_PIXEL_ macros return corresponding values |
||
2999 | * for the pixels and will always return 1 for color-mapped formats. The |
||
3000 | * remaining macros return information about the rows in the image and the |
||
3001 | * complete image. |
||
3002 | * |
||
3003 | * NOTE: All the macros that take a png_image::format parameter are compile time |
||
3004 | * constants if the format parameter is, itself, a constant. Therefore these |
||
3005 | * macros can be used in array declarations and case labels where required. |
||
3006 | * Similarly the macros are also pre-processor constants (sizeof is not used) so |
||
3007 | * they can be used in #if tests. |
||
3008 | * |
||
3009 | * First the information about the samples. |
||
3010 | */ |
||
3011 | #define PNG_IMAGE_SAMPLE_CHANNELS(fmt)\ |
||
3012 | (((fmt)&(PNG_FORMAT_FLAG_COLOR|PNG_FORMAT_FLAG_ALPHA))+1) |
||
3013 | /* Return the total number of channels in a given format: 1..4 */ |
||
3014 | |||
3015 | |||
3016 | ((((fmt) & PNG_FORMAT_FLAG_LINEAR) >> 2)+1) |
||
3017 | /* Return the size in bytes of a single component of a pixel or color-map |
||
3018 | * entry (as appropriate) in the image: 1 or 2. |
||
3019 | */ |
||
3020 | |||
3021 | |||
3022 | (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * PNG_IMAGE_SAMPLE_COMPONENT_SIZE(fmt)) |
||
3023 | /* This is the size of the sample data for one sample. If the image is |
||
3024 | * color-mapped it is the size of one color-map entry (and image pixels are |
||
3025 | * one byte in size), otherwise it is the size of one image pixel. |
||
3026 | */ |
||
3027 | |||
3028 | |||
3029 | (PNG_IMAGE_SAMPLE_CHANNELS(fmt) * 256) |
||
3030 | /* The maximum size of the color-map required by the format expressed in a |
||
3031 | * count of components. This can be used to compile-time allocate a |
||
3032 | * color-map: |
||
3033 | * |
||
3034 | * png_uint_16 colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(linear_fmt)]; |
||
3035 | * |
||
3036 | * png_byte colormap[PNG_IMAGE_MAXIMUM_COLORMAP_COMPONENTS(sRGB_fmt)]; |
||
3037 | * |
||
3038 | * Alternatively use the PNG_IMAGE_COLORMAP_SIZE macro below to use the |
||
3039 | * information from one of the png_image_begin_read_ APIs and dynamically |
||
3040 | * allocate the required memory. |
||
3041 | */ |
||
3042 | |||
3043 | |||
3044 | #define PNG_IMAGE_PIXEL_(test,fmt)\ |
||
3045 | (((fmt)&PNG_FORMAT_FLAG_COLORMAP)?1:test(fmt)) |
||
3046 | |||
3047 | |||
3048 | PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_CHANNELS,fmt) |
||
3049 | /* The number of separate channels (components) in a pixel; 1 for a |
||
3050 | * color-mapped image. |
||
3051 | */ |
||
3052 | |||
3053 | |||
3054 | PNG_IMAGE_PIXEL_(PNG_IMAGE_SAMPLE_COMPONENT_SIZE,fmt) |
||
3055 | /* The size, in bytes, of each component in a pixel; 1 for a color-mapped |
||
3056 | * image. |
||
3057 | */ |
||
3058 | |||
3059 | |||
3060 | /* The size, in bytes, of a complete pixel; 1 for a color-mapped image. */ |
||
3061 | |||
3062 | |||
3063 | #define PNG_IMAGE_ROW_STRIDE(image)\ |
||
3064 | (PNG_IMAGE_PIXEL_CHANNELS((image).format) * (image).width) |
||
3065 | /* Return the total number of components in a single row of the image; this |
||
3066 | * is the minimum 'row stride', the minimum count of components between each |
||
3067 | * row. For a color-mapped image this is the minimum number of bytes in a |
||
3068 | * row. |
||
3069 | */ |
||
3070 | |||
3071 | |||
3072 | (PNG_IMAGE_PIXEL_COMPONENT_SIZE((image).format)*(image).height*(row_stride)) |
||
3073 | /* Return the size, in bytes, of an image buffer given a png_image and a row |
||
3074 | * stride - the number of components to leave space for in each row. |
||
3075 | */ |
||
3076 | |||
3077 | |||
3078 | PNG_IMAGE_BUFFER_SIZE(image, PNG_IMAGE_ROW_STRIDE(image)) |
||
3079 | /* Return the size, in bytes, of the image in memory given just a png_image; |
||
3080 | * the row stride is the minimum stride required for the image. |
||
3081 | */ |
||
3082 | |||
3083 | |||
3084 | (PNG_IMAGE_SAMPLE_SIZE((image).format) * (image).colormap_entries) |
||
3085 | /* Return the size, in bytes, of the color-map of this image. If the image |
||
3086 | * format is not a color-map format this will return a size sufficient for |
||
3087 | * 256 entries in the given format; check PNG_FORMAT_FLAG_COLORMAP if |
||
3088 | * you don't want to allocate a color-map in this case. |
||
3089 | */ |
||
3090 | |||
3091 | |||
3092 | * |
||
3093 | * Flags containing additional information about the image are held in the |
||
3094 | * 'flags' field of png_image. |
||
3095 | */ |
||
3096 | #define PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB 0x01 |
||
3097 | /* This indicates the the RGB values of the in-memory bitmap do not |
||
3098 | * correspond to the red, green and blue end-points defined by sRGB. |
||
3099 | */ |
||
3100 | |||
3101 | |||
3102 | /* On write emphasise speed over compression; the resultant PNG file will be |
||
3103 | * larger but will be produced significantly faster, particular for large |
||
3104 | * images. Do not use this option for images which will be distributed, only |
||
3105 | * used it when producing intermediate files that will be read back in |
||
3106 | * repeatedly. For a typical 24-bit image the option will double the read |
||
3107 | * speed at the cost of increasing the image size by 25%, however for many |
||
3108 | * more compressible images the PNG file can be 10 times larger with only a |
||
3109 | * slight speed gain. |
||
3110 | */ |
||
3111 | |||
3112 | |||
3113 | /* On read if the image is a 16-bit per component image and there is no gAMA |
||
3114 | * or sRGB chunk assume that the components are sRGB encoded. Notice that |
||
3115 | * images output by the simplified API always have gamma information; setting |
||
3116 | * this flag only affects the interpretation of 16-bit images from an |
||
3117 | * external source. It is recommended that the application expose this flag |
||
3118 | * to the user; the user can normally easily recognize the difference between |
||
3119 | * linear and sRGB encoding. This flag has no effect on write - the data |
||
3120 | * passed to the write APIs must have the correct encoding (as defined |
||
3121 | * above.) |
||
3122 | * |
||
3123 | * If the flag is not set (the default) input 16-bit per component data is |
||
3124 | * assumed to be linear. |
||
3125 | * |
||
3126 | * NOTE: the flag can only be set after the png_image_begin_read_ call, |
||
3127 | * because that call initializes the 'flags' field. |
||
3128 | */ |
||
3129 | |||
3130 | |||
3131 | /* READ APIs |
||
3132 | * --------- |
||
3133 | * |
||
3134 | * The png_image passed to the read APIs must have been initialized by setting |
||
3135 | * the png_controlp field 'opaque' to NULL (or, safer, memset the whole thing.) |
||
3136 | */ |
||
3137 | #ifdef PNG_STDIO_SUPPORTED |
||
3138 | PNG_EXPORT(234, int, png_image_begin_read_from_file, (png_imagep image, |
||
3139 | const char *file_name)); |
||
3140 | /* The named file is opened for read and the image header is filled in |
||
3141 | * from the PNG header in the file. |
||
3142 | */ |
||
3143 | |||
3144 | |||
3145 | FILE* file)); |
||
3146 | /* The PNG header is read from the stdio FILE object. */ |
||
3147 | #endif /* PNG_STDIO_SUPPORTED */ |
||
3148 | |||
3149 | |||
3150 | png_const_voidp memory, png_size_t size)); |
||
3151 | /* The PNG header is read from the given memory buffer. */ |
||
3152 | |||
3153 | |||
3154 | png_const_colorp background, void *buffer, png_int_32 row_stride, |
||
3155 | void *colormap)); |
||
3156 | /* Finish reading the image into the supplied buffer and clean up the |
||
3157 | * png_image structure. |
||
3158 | * |
||
3159 | * row_stride is the step, in byte or 2-byte units as appropriate, |
||
3160 | * between adjacent rows. A positive stride indicates that the top-most row |
||
3161 | * is first in the buffer - the normal top-down arrangement. A negative |
||
3162 | * stride indicates that the bottom-most row is first in the buffer. |
||
3163 | * |
||
3164 | * background need only be supplied if an alpha channel must be removed from |
||
3165 | * a png_byte format and the removal is to be done by compositing on a solid |
||
3166 | * color; otherwise it may be NULL and any composition will be done directly |
||
3167 | * onto the buffer. The value is an sRGB color to use for the background, |
||
3168 | * for grayscale output the green channel is used. |
||
3169 | * |
||
3170 | * background must be supplied when an alpha channel must be removed from a |
||
3171 | * single byte color-mapped output format, in other words if: |
||
3172 | * |
||
3173 | * 1) The original format from png_image_begin_read_from_* had |
||
3174 | * PNG_FORMAT_FLAG_ALPHA set. |
||
3175 | * 2) The format set by the application does not. |
||
3176 | * 3) The format set by the application has PNG_FORMAT_FLAG_COLORMAP set and |
||
3177 | * PNG_FORMAT_FLAG_LINEAR *not* set. |
||
3178 | * |
||
3179 | * For linear output removing the alpha channel is always done by compositing |
||
3180 | * on black and background is ignored. |
||
3181 | * |
||
3182 | * colormap must be supplied when PNG_FORMAT_FLAG_COLORMAP is set. It must |
||
3183 | * be at least the size (in bytes) returned by PNG_IMAGE_COLORMAP_SIZE. |
||
3184 | * image->colormap_entries will be updated to the actual number of entries |
||
3185 | * written to the colormap; this may be less than the original value. |
||
3186 | */ |
||
3187 | |||
3188 | |||
3189 | /* Free any data allocated by libpng in image->opaque, setting the pointer to |
||
3190 | * NULL. May be called at any time after the structure is initialized. |
||
3191 | */ |
||
3192 | #endif /* PNG_SIMPLIFIED_READ_SUPPORTED */ |
||
3193 | |||
3194 | |||
3195 | #ifdef PNG_STDIO_SUPPORTED |
||
3196 | /* WRITE APIS |
||
3197 | * ---------- |
||
3198 | * For write you must initialize a png_image structure to describe the image to |
||
3199 | * be written. To do this use memset to set the whole structure to 0 then |
||
3200 | * initialize fields describing your image. |
||
3201 | * |
||
3202 | * version: must be set to PNG_IMAGE_VERSION |
||
3203 | * opaque: must be initialized to NULL |
||
3204 | * width: image width in pixels |
||
3205 | * height: image height in rows |
||
3206 | * format: the format of the data (image and color-map) you wish to write |
||
3207 | * flags: set to 0 unless one of the defined flags applies; set |
||
3208 | * PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB for color format images where the RGB |
||
3209 | * values do not correspond to the colors in sRGB. |
||
3210 | * colormap_entries: set to the number of entries in the color-map (0 to 256) |
||
3211 | */ |
||
3212 | PNG_EXPORT(239, int, png_image_write_to_file, (png_imagep image, |
||
3213 | const char *file, int convert_to_8bit, const void *buffer, |
||
3214 | png_int_32 row_stride, const void *colormap)); |
||
3215 | /* Write the image to the named file. */ |
||
3216 | |||
3217 | |||
3218 | int convert_to_8_bit, const void *buffer, png_int_32 row_stride, |
||
3219 | const void *colormap)); |
||
3220 | /* Write the image to the given (FILE*). */ |
||
3221 | |||
3222 | |||
3223 | * data then setting convert_to_8_bit will cause the output to be an 8-bit PNG |
||
3224 | * gamma encoded according to the sRGB specification, otherwise a 16-bit linear |
||
3225 | * encoded PNG file is written. |
||
3226 | * |
||
3227 | * With color-mapped data formats the colormap parameter point to a color-map |
||
3228 | * with at least image->colormap_entries encoded in the specified format. If |
||
3229 | * the format is linear the written PNG color-map will be converted to sRGB |
||
3230 | * regardless of the convert_to_8_bit flag. |
||
3231 | * |
||
3232 | * With all APIs row_stride is handled as in the read APIs - it is the spacing |
||
3233 | * from one row to the next in component sized units (1 or 2 bytes) and if |
||
3234 | * negative indicates a bottom-up row layout in the buffer. |
||
3235 | * |
||
3236 | * Note that the write API does not support interlacing or sub-8-bit pixels. |
||
3237 | */ |
||
3238 | #endif /* PNG_STDIO_SUPPORTED */ |
||
3239 | #endif /* PNG_SIMPLIFIED_WRITE_SUPPORTED */ |
||
3240 | /******************************************************************************* |
||
3241 | * END OF SIMPLIFIED API |
||
3242 | ******************************************************************************/ |
||
3243 | |||
3244 | |||
3245 | PNG_EXPORT(242, void, png_set_check_for_invalid_index, |
||
3246 | (png_structrp png_ptr, int allowed)); |
||
3247 | # ifdef PNG_GET_PALETTE_MAX_SUPPORTED |
||
3248 | PNG_EXPORT(243, int, png_get_palette_max, (png_const_structp png_ptr, |
||
3249 | png_const_infop info_ptr)); |
||
3250 | # endif |
||
3251 | #endif /* CHECK_FOR_INVALID_INDEX */ |
||
3252 | |||
3253 | |||
3254 | * IMPLEMENTATION OPTIONS |
||
3255 | ******************************************************************************* |
||
3256 | * |
||
3257 | * Support for arbitrary implementation-specific optimizations. The API allows |
||
3258 | * particular options to be turned on or off. 'Option' is the number of the |
||
3259 | * option and 'onoff' is 0 (off) or non-0 (on). The value returned is given |
||
3260 | * by the PNG_OPTION_ defines below. |
||
3261 | * |
||
3262 | * HARDWARE: normally hardware capabilites, such as the Intel SSE instructions, |
||
3263 | * are detected at run time, however sometimes it may be impossible |
||
3264 | * to do this in user mode, in which case it is necessary to discover |
||
3265 | * the capabilities in an OS specific way. Such capabilities are |
||
3266 | * listed here when libpng has support for them and must be turned |
||
3267 | * ON by the application if present. |
||
3268 | * |
||
3269 | * SOFTWARE: sometimes software optimizations actually result in performance |
||
3270 | * decrease on some architectures or systems, or with some sets of |
||
3271 | * PNG images. 'Software' options allow such optimizations to be |
||
3272 | * selected at run time. |
||
3273 | */ |
||
3274 | #ifdef PNG_SET_OPTION_SUPPORTED |
||
3275 | #ifdef PNG_ARM_NEON_API_SUPPORTED |
||
3276 | # define PNG_ARM_NEON 0 /* HARDWARE: ARM Neon SIMD instructions supported */ |
||
3277 | #endif |
||
3278 | #define PNG_MAXIMUM_INFLATE_WINDOW 2 /* SOFTWARE: force maximum window */ |
||
3279 | #define PNG_OPTION_NEXT 4 /* Next option - numbers must be even */ |
||
3280 | |||
3281 | |||
3282 | #define PNG_OPTION_UNSET 0 /* Unset - defaults to off */ |
||
3283 | #define PNG_OPTION_INVALID 1 /* Option number out of range */ |
||
3284 | #define PNG_OPTION_OFF 2 |
||
3285 | #define PNG_OPTION_ON 3 |
||
3286 | |||
3287 | |||
3288 | int onoff)); |
||
3289 | #endif |
||
3290 | |||
3291 | |||
3292 | * END OF HARDWARE OPTIONS |
||
3293 | ******************************************************************************/ |
||
3294 | |||
3295 | |||
3296 | * defs, scripts/pnglibconf.h, and scripts/pnglibconf.h.prebuilt |
||
3297 | */ |
||
3298 | |||
3299 | |||
3300 | * one to use is one more than this.) Maintainer, remember to add an entry to |
||
3301 | * scripts/symbols.def as well. |
||
3302 | */ |
||
3303 | #ifdef PNG_EXPORT_LAST_ORDINAL |
||
3304 | PNG_EXPORT_LAST_ORDINAL(244); |
||
3305 | #endif |
||
3306 | |||
3307 | |||
3308 | } |
||
3309 | #endif |
||
3310 | |||
3311 | |||
3312 | /* Do not put anything past this line */ |
||
3313 | #endif /* PNG_H */><>><>><>><>2))><2))>2))><2))> |
||
3314 |