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Rev | Author | Line No. | Line |
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4349 | Serge | 1 | /* |
2 | * American Laser Games MM Video Decoder |
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3 | * Copyright (c) 2006,2008 Peter Ross |
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4 | * |
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5 | * This file is part of FFmpeg. |
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6 | * |
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7 | * FFmpeg is free software; you can redistribute it and/or |
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8 | * modify it under the terms of the GNU Lesser General Public |
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9 | * License as published by the Free Software Foundation; either |
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10 | * version 2.1 of the License, or (at your option) any later version. |
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11 | * |
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12 | * FFmpeg is distributed in the hope that it will be useful, |
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13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
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14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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15 | * Lesser General Public License for more details. |
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16 | * |
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17 | * You should have received a copy of the GNU Lesser General Public |
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18 | * License along with FFmpeg; if not, write to the Free Software |
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19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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20 | */ |
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21 | |||
22 | /** |
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23 | * @file |
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24 | * American Laser Games MM Video Decoder |
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25 | * by Peter Ross (pross@xvid.org) |
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26 | * |
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27 | * The MM format was used by IBM-PC ports of ALG's "arcade shooter" games, |
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28 | * including Mad Dog McCree and Crime Patrol. |
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29 | * |
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30 | * Technical details here: |
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31 | * http://wiki.multimedia.cx/index.php?title=American_Laser_Games_MM |
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32 | */ |
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33 | |||
34 | #include "libavutil/intreadwrite.h" |
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35 | #include "avcodec.h" |
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36 | #include "bytestream.h" |
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37 | #include "internal.h" |
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38 | |||
39 | #define MM_PREAMBLE_SIZE 6 |
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40 | |||
41 | #define MM_TYPE_INTER 0x5 |
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42 | #define MM_TYPE_INTRA 0x8 |
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43 | #define MM_TYPE_INTRA_HH 0xc |
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44 | #define MM_TYPE_INTER_HH 0xd |
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45 | #define MM_TYPE_INTRA_HHV 0xe |
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46 | #define MM_TYPE_INTER_HHV 0xf |
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47 | #define MM_TYPE_PALETTE 0x31 |
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48 | |||
49 | typedef struct MmContext { |
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50 | AVCodecContext *avctx; |
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51 | AVFrame frame; |
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52 | int palette[AVPALETTE_COUNT]; |
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53 | GetByteContext gb; |
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54 | } MmContext; |
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55 | |||
56 | static av_cold int mm_decode_init(AVCodecContext *avctx) |
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57 | { |
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58 | MmContext *s = avctx->priv_data; |
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59 | |||
60 | s->avctx = avctx; |
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61 | |||
62 | avctx->pix_fmt = AV_PIX_FMT_PAL8; |
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63 | |||
64 | avcodec_get_frame_defaults(&s->frame); |
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65 | |||
66 | return 0; |
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67 | } |
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68 | |||
69 | static int mm_decode_pal(MmContext *s) |
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70 | { |
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71 | int i; |
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72 | |||
73 | bytestream2_skip(&s->gb, 4); |
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74 | for (i = 0; i < 128; i++) { |
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75 | s->palette[i] = 0xFFU << 24 | bytestream2_get_be24(&s->gb); |
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76 | s->palette[i+128] = s->palette[i]<<2; |
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77 | } |
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78 | |||
79 | return 0; |
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80 | } |
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81 | |||
82 | /** |
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83 | * @param half_horiz Half horizontal resolution (0 or 1) |
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84 | * @param half_vert Half vertical resolution (0 or 1) |
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85 | */ |
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86 | static int mm_decode_intra(MmContext * s, int half_horiz, int half_vert) |
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87 | { |
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88 | int x = 0, y = 0; |
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89 | |||
90 | while (bytestream2_get_bytes_left(&s->gb) > 0) { |
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91 | int run_length, color; |
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92 | |||
93 | if (y >= s->avctx->height) |
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94 | return 0; |
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95 | |||
96 | color = bytestream2_get_byte(&s->gb); |
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97 | if (color & 0x80) { |
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98 | run_length = 1; |
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99 | }else{ |
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100 | run_length = (color & 0x7f) + 2; |
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101 | color = bytestream2_get_byte(&s->gb); |
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102 | } |
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103 | |||
104 | if (half_horiz) |
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105 | run_length *=2; |
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106 | |||
107 | if (run_length > s->avctx->width - x) |
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108 | return AVERROR_INVALIDDATA; |
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109 | |||
110 | if (color) { |
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111 | memset(s->frame.data[0] + y*s->frame.linesize[0] + x, color, run_length); |
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112 | if (half_vert) |
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113 | memset(s->frame.data[0] + (y+1)*s->frame.linesize[0] + x, color, run_length); |
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114 | } |
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115 | x+= run_length; |
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116 | |||
117 | if (x >= s->avctx->width) { |
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118 | x=0; |
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119 | y += 1 + half_vert; |
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120 | } |
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121 | } |
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122 | |||
123 | return 0; |
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124 | } |
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125 | |||
126 | /** |
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127 | * @param half_horiz Half horizontal resolution (0 or 1) |
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128 | * @param half_vert Half vertical resolution (0 or 1) |
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129 | */ |
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130 | static int mm_decode_inter(MmContext * s, int half_horiz, int half_vert) |
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131 | { |
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132 | int data_off = bytestream2_get_le16(&s->gb), y = 0; |
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133 | GetByteContext data_ptr; |
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134 | |||
135 | if (bytestream2_get_bytes_left(&s->gb) < data_off) |
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136 | return AVERROR_INVALIDDATA; |
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137 | |||
138 | bytestream2_init(&data_ptr, s->gb.buffer + data_off, bytestream2_get_bytes_left(&s->gb) - data_off); |
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139 | while (s->gb.buffer < data_ptr.buffer_start) { |
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140 | int i, j; |
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141 | int length = bytestream2_get_byte(&s->gb); |
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142 | int x = bytestream2_get_byte(&s->gb) + ((length & 0x80) << 1); |
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143 | length &= 0x7F; |
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144 | |||
145 | if (length==0) { |
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146 | y += x; |
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147 | continue; |
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148 | } |
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149 | |||
150 | if (y + half_vert >= s->avctx->height) |
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151 | return 0; |
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152 | |||
153 | for(i=0; i |
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154 | int replace_array = bytestream2_get_byte(&s->gb); |
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155 | for(j=0; j<8; j++) { |
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156 | int replace = (replace_array >> (7-j)) & 1; |
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157 | if (x + half_horiz >= s->avctx->width) |
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158 | return AVERROR_INVALIDDATA; |
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159 | if (replace) { |
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160 | int color = bytestream2_get_byte(&data_ptr); |
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161 | s->frame.data[0][y*s->frame.linesize[0] + x] = color; |
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162 | if (half_horiz) |
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163 | s->frame.data[0][y*s->frame.linesize[0] + x + 1] = color; |
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164 | if (half_vert) { |
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165 | s->frame.data[0][(y+1)*s->frame.linesize[0] + x] = color; |
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166 | if (half_horiz) |
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167 | s->frame.data[0][(y+1)*s->frame.linesize[0] + x + 1] = color; |
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168 | } |
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169 | } |
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170 | x += 1 + half_horiz; |
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171 | } |
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172 | } |
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173 | |||
174 | y += 1 + half_vert; |
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175 | } |
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176 | |||
177 | return 0; |
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178 | } |
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179 | |||
180 | static int mm_decode_frame(AVCodecContext *avctx, |
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181 | void *data, int *got_frame, |
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182 | AVPacket *avpkt) |
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183 | { |
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184 | const uint8_t *buf = avpkt->data; |
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185 | int buf_size = avpkt->size; |
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186 | MmContext *s = avctx->priv_data; |
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187 | int type, res; |
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188 | |||
189 | if (buf_size < MM_PREAMBLE_SIZE) |
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190 | return AVERROR_INVALIDDATA; |
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191 | type = AV_RL16(&buf[0]); |
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192 | buf += MM_PREAMBLE_SIZE; |
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193 | buf_size -= MM_PREAMBLE_SIZE; |
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194 | bytestream2_init(&s->gb, buf, buf_size); |
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195 | |||
196 | if ((res = ff_reget_buffer(avctx, &s->frame)) < 0) |
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197 | return res; |
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198 | |||
199 | switch(type) { |
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200 | case MM_TYPE_PALETTE : res = mm_decode_pal(s); return avpkt->size; |
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201 | case MM_TYPE_INTRA : res = mm_decode_intra(s, 0, 0); break; |
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202 | case MM_TYPE_INTRA_HH : res = mm_decode_intra(s, 1, 0); break; |
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203 | case MM_TYPE_INTRA_HHV : res = mm_decode_intra(s, 1, 1); break; |
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204 | case MM_TYPE_INTER : res = mm_decode_inter(s, 0, 0); break; |
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205 | case MM_TYPE_INTER_HH : res = mm_decode_inter(s, 1, 0); break; |
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206 | case MM_TYPE_INTER_HHV : res = mm_decode_inter(s, 1, 1); break; |
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207 | default: |
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208 | res = AVERROR_INVALIDDATA; |
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209 | break; |
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210 | } |
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211 | if (res < 0) |
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212 | return res; |
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213 | |||
214 | memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE); |
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215 | |||
216 | if ((res = av_frame_ref(data, &s->frame)) < 0) |
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217 | return res; |
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218 | |||
219 | *got_frame = 1; |
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220 | |||
221 | return avpkt->size; |
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222 | } |
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223 | |||
224 | static av_cold int mm_decode_end(AVCodecContext *avctx) |
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225 | { |
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226 | MmContext *s = avctx->priv_data; |
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227 | |||
228 | av_frame_unref(&s->frame); |
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229 | |||
230 | return 0; |
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231 | } |
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232 | |||
233 | AVCodec ff_mmvideo_decoder = { |
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234 | .name = "mmvideo", |
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235 | .long_name = NULL_IF_CONFIG_SMALL("American Laser Games MM Video"), |
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236 | .type = AVMEDIA_TYPE_VIDEO, |
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237 | .id = AV_CODEC_ID_MMVIDEO, |
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238 | .priv_data_size = sizeof(MmContext), |
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239 | .init = mm_decode_init, |
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240 | .close = mm_decode_end, |
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241 | .decode = mm_decode_frame, |
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242 | .capabilities = CODEC_CAP_DR1, |
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243 | };>>>>8;>><>>>2; |