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Rev | Author | Line No. | Line |
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6148 | serge | 1 | /* |
2 | * ALAC (Apple Lossless Audio Codec) decoder |
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3 | * Copyright (c) 2005 David Hammerton |
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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 | * ALAC (Apple Lossless Audio Codec) decoder |
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25 | * @author 2005 David Hammerton |
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26 | * @see http://crazney.net/programs/itunes/alac.html |
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27 | * |
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28 | * Note: This decoder expects a 36-byte QuickTime atom to be |
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29 | * passed through the extradata[_size] fields. This atom is tacked onto |
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30 | * the end of an 'alac' stsd atom and has the following format: |
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31 | * |
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32 | * 32bit atom size |
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33 | * 32bit tag ("alac") |
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34 | * 32bit tag version (0) |
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35 | * 32bit samples per frame (used when not set explicitly in the frames) |
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36 | * 8bit compatible version (0) |
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37 | * 8bit sample size |
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38 | * 8bit history mult (40) |
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39 | * 8bit initial history (10) |
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40 | * 8bit rice param limit (14) |
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41 | * 8bit channels |
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42 | * 16bit maxRun (255) |
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43 | * 32bit max coded frame size (0 means unknown) |
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44 | * 32bit average bitrate (0 means unknown) |
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45 | * 32bit samplerate |
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46 | */ |
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47 | |||
48 | #include "libavutil/channel_layout.h" |
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49 | #include "avcodec.h" |
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50 | #include "get_bits.h" |
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51 | #include "bytestream.h" |
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52 | #include "internal.h" |
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53 | #include "thread.h" |
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54 | #include "unary.h" |
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55 | #include "mathops.h" |
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56 | #include "alac_data.h" |
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57 | |||
58 | #define ALAC_EXTRADATA_SIZE 36 |
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59 | |||
60 | typedef struct { |
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61 | AVCodecContext *avctx; |
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62 | GetBitContext gb; |
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63 | int channels; |
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64 | |||
65 | int32_t *predict_error_buffer[2]; |
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66 | int32_t *output_samples_buffer[2]; |
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67 | int32_t *extra_bits_buffer[2]; |
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68 | |||
69 | uint32_t max_samples_per_frame; |
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70 | uint8_t sample_size; |
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71 | uint8_t rice_history_mult; |
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72 | uint8_t rice_initial_history; |
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73 | uint8_t rice_limit; |
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74 | |||
75 | int extra_bits; /**< number of extra bits beyond 16-bit */ |
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76 | int nb_samples; /**< number of samples in the current frame */ |
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77 | |||
78 | int direct_output; |
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79 | } ALACContext; |
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80 | |||
81 | static inline unsigned int decode_scalar(GetBitContext *gb, int k, int bps) |
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82 | { |
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83 | unsigned int x = get_unary_0_9(gb); |
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84 | |||
85 | if (x > 8) { /* RICE THRESHOLD */ |
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86 | /* use alternative encoding */ |
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87 | x = get_bits_long(gb, bps); |
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88 | } else if (k != 1) { |
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89 | int extrabits = show_bits(gb, k); |
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90 | |||
91 | /* multiply x by 2^k - 1, as part of their strange algorithm */ |
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92 | x = (x << k) - x; |
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93 | |||
94 | if (extrabits > 1) { |
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95 | x += extrabits - 1; |
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96 | skip_bits(gb, k); |
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97 | } else |
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98 | skip_bits(gb, k - 1); |
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99 | } |
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100 | return x; |
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101 | } |
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102 | |||
103 | static int rice_decompress(ALACContext *alac, int32_t *output_buffer, |
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104 | int nb_samples, int bps, int rice_history_mult) |
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105 | { |
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106 | int i; |
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107 | unsigned int history = alac->rice_initial_history; |
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108 | int sign_modifier = 0; |
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109 | |||
110 | for (i = 0; i < nb_samples; i++) { |
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111 | int k; |
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112 | unsigned int x; |
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113 | |||
114 | if(get_bits_left(&alac->gb) <= 0) |
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115 | return -1; |
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116 | |||
117 | /* calculate rice param and decode next value */ |
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118 | k = av_log2((history >> 9) + 3); |
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119 | k = FFMIN(k, alac->rice_limit); |
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120 | x = decode_scalar(&alac->gb, k, bps); |
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121 | x += sign_modifier; |
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122 | sign_modifier = 0; |
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123 | output_buffer[i] = (x >> 1) ^ -(x & 1); |
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124 | |||
125 | /* update the history */ |
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126 | if (x > 0xffff) |
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127 | history = 0xffff; |
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128 | else |
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129 | history += x * rice_history_mult - |
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130 | ((history * rice_history_mult) >> 9); |
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131 | |||
132 | /* special case: there may be compressed blocks of 0 */ |
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133 | if ((history < 128) && (i + 1 < nb_samples)) { |
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134 | int block_size; |
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135 | |||
136 | /* calculate rice param and decode block size */ |
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137 | k = 7 - av_log2(history) + ((history + 16) >> 6); |
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138 | k = FFMIN(k, alac->rice_limit); |
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139 | block_size = decode_scalar(&alac->gb, k, 16); |
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140 | |||
141 | if (block_size > 0) { |
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142 | if (block_size >= nb_samples - i) { |
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143 | av_log(alac->avctx, AV_LOG_ERROR, |
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144 | "invalid zero block size of %d %d %d\n", block_size, |
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145 | nb_samples, i); |
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146 | block_size = nb_samples - i - 1; |
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147 | } |
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148 | memset(&output_buffer[i + 1], 0, |
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149 | block_size * sizeof(*output_buffer)); |
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150 | i += block_size; |
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151 | } |
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152 | if (block_size <= 0xffff) |
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153 | sign_modifier = 1; |
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154 | history = 0; |
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155 | } |
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156 | } |
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157 | return 0; |
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158 | } |
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159 | |||
160 | static inline int sign_only(int v) |
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161 | { |
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162 | return v ? FFSIGN(v) : 0; |
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163 | } |
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164 | |||
165 | static void lpc_prediction(int32_t *error_buffer, int32_t *buffer_out, |
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166 | int nb_samples, int bps, int16_t *lpc_coefs, |
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167 | int lpc_order, int lpc_quant) |
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168 | { |
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169 | int i; |
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170 | int32_t *pred = buffer_out; |
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171 | |||
172 | /* first sample always copies */ |
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173 | *buffer_out = *error_buffer; |
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174 | |||
175 | if (nb_samples <= 1) |
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176 | return; |
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177 | |||
178 | if (!lpc_order) { |
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179 | memcpy(&buffer_out[1], &error_buffer[1], |
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180 | (nb_samples - 1) * sizeof(*buffer_out)); |
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181 | return; |
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182 | } |
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183 | |||
184 | if (lpc_order == 31) { |
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185 | /* simple 1st-order prediction */ |
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186 | for (i = 1; i < nb_samples; i++) { |
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187 | buffer_out[i] = sign_extend(buffer_out[i - 1] + error_buffer[i], |
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188 | bps); |
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189 | } |
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190 | return; |
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191 | } |
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192 | |||
193 | /* read warm-up samples */ |
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194 | for (i = 1; i <= lpc_order && i < nb_samples; i++) |
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195 | buffer_out[i] = sign_extend(buffer_out[i - 1] + error_buffer[i], bps); |
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196 | |||
197 | /* NOTE: 4 and 8 are very common cases that could be optimized. */ |
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198 | |||
199 | for (; i < nb_samples; i++) { |
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200 | int j; |
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201 | int val = 0; |
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202 | int error_val = error_buffer[i]; |
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203 | int error_sign; |
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204 | int d = *pred++; |
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205 | |||
206 | /* LPC prediction */ |
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207 | for (j = 0; j < lpc_order; j++) |
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208 | val += (pred[j] - d) * lpc_coefs[j]; |
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209 | val = (val + (1 << (lpc_quant - 1))) >> lpc_quant; |
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210 | val += d + error_val; |
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211 | buffer_out[i] = sign_extend(val, bps); |
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212 | |||
213 | /* adapt LPC coefficients */ |
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214 | error_sign = sign_only(error_val); |
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215 | if (error_sign) { |
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216 | for (j = 0; j < lpc_order && error_val * error_sign > 0; j++) { |
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217 | int sign; |
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218 | val = d - pred[j]; |
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219 | sign = sign_only(val) * error_sign; |
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220 | lpc_coefs[j] -= sign; |
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221 | val *= sign; |
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222 | error_val -= (val >> lpc_quant) * (j + 1); |
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223 | } |
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224 | } |
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225 | } |
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226 | } |
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227 | |||
228 | static void decorrelate_stereo(int32_t *buffer[2], int nb_samples, |
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229 | int decorr_shift, int decorr_left_weight) |
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230 | { |
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231 | int i; |
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232 | |||
233 | for (i = 0; i < nb_samples; i++) { |
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234 | int32_t a, b; |
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235 | |||
236 | a = buffer[0][i]; |
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237 | b = buffer[1][i]; |
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238 | |||
239 | a -= (b * decorr_left_weight) >> decorr_shift; |
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240 | b += a; |
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241 | |||
242 | buffer[0][i] = b; |
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243 | buffer[1][i] = a; |
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244 | } |
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245 | } |
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246 | |||
247 | static void append_extra_bits(int32_t *buffer[2], int32_t *extra_bits_buffer[2], |
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248 | int extra_bits, int channels, int nb_samples) |
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249 | { |
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250 | int i, ch; |
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251 | |||
252 | for (ch = 0; ch < channels; ch++) |
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253 | for (i = 0; i < nb_samples; i++) |
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254 | buffer[ch][i] = (buffer[ch][i] << extra_bits) | extra_bits_buffer[ch][i]; |
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255 | } |
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256 | |||
257 | static int decode_element(AVCodecContext *avctx, AVFrame *frame, int ch_index, |
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258 | int channels) |
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259 | { |
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260 | ALACContext *alac = avctx->priv_data; |
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261 | int has_size, bps, is_compressed, decorr_shift, decorr_left_weight, ret; |
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262 | uint32_t output_samples; |
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263 | int i, ch; |
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264 | |||
265 | skip_bits(&alac->gb, 4); /* element instance tag */ |
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266 | skip_bits(&alac->gb, 12); /* unused header bits */ |
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267 | |||
268 | /* the number of output samples is stored in the frame */ |
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269 | has_size = get_bits1(&alac->gb); |
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270 | |||
271 | alac->extra_bits = get_bits(&alac->gb, 2) << 3; |
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272 | bps = alac->sample_size - alac->extra_bits + channels - 1; |
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273 | if (bps > 32U) { |
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274 | av_log(avctx, AV_LOG_ERROR, "bps is unsupported: %d\n", bps); |
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275 | return AVERROR_PATCHWELCOME; |
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276 | } |
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277 | |||
278 | /* whether the frame is compressed */ |
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279 | is_compressed = !get_bits1(&alac->gb); |
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280 | |||
281 | if (has_size) |
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282 | output_samples = get_bits_long(&alac->gb, 32); |
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283 | else |
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284 | output_samples = alac->max_samples_per_frame; |
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285 | if (!output_samples || output_samples > alac->max_samples_per_frame) { |
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286 | av_log(avctx, AV_LOG_ERROR, "invalid samples per frame: %d\n", |
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287 | output_samples); |
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288 | return AVERROR_INVALIDDATA; |
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289 | } |
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290 | if (!alac->nb_samples) { |
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291 | ThreadFrame tframe = { .f = frame }; |
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292 | /* get output buffer */ |
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293 | frame->nb_samples = output_samples; |
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294 | if ((ret = ff_thread_get_buffer(avctx, &tframe, 0)) < 0) |
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295 | return ret; |
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296 | } else if (output_samples != alac->nb_samples) { |
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297 | av_log(avctx, AV_LOG_ERROR, "sample count mismatch: %u != %d\n", |
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298 | output_samples, alac->nb_samples); |
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299 | return AVERROR_INVALIDDATA; |
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300 | } |
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301 | alac->nb_samples = output_samples; |
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302 | if (alac->direct_output) { |
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303 | for (ch = 0; ch < channels; ch++) |
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304 | alac->output_samples_buffer[ch] = (int32_t *)frame->extended_data[ch_index + ch]; |
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305 | } |
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306 | |||
307 | if (is_compressed) { |
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308 | int16_t lpc_coefs[2][32]; |
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309 | int lpc_order[2]; |
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310 | int prediction_type[2]; |
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311 | int lpc_quant[2]; |
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312 | int rice_history_mult[2]; |
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313 | |||
314 | decorr_shift = get_bits(&alac->gb, 8); |
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315 | decorr_left_weight = get_bits(&alac->gb, 8); |
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316 | |||
317 | for (ch = 0; ch < channels; ch++) { |
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318 | prediction_type[ch] = get_bits(&alac->gb, 4); |
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319 | lpc_quant[ch] = get_bits(&alac->gb, 4); |
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320 | rice_history_mult[ch] = get_bits(&alac->gb, 3); |
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321 | lpc_order[ch] = get_bits(&alac->gb, 5); |
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322 | |||
323 | if (lpc_order[ch] >= alac->max_samples_per_frame) |
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324 | return AVERROR_INVALIDDATA; |
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325 | |||
326 | /* read the predictor table */ |
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327 | for (i = lpc_order[ch] - 1; i >= 0; i--) |
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328 | lpc_coefs[ch][i] = get_sbits(&alac->gb, 16); |
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329 | } |
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330 | |||
331 | if (alac->extra_bits) { |
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332 | for (i = 0; i < alac->nb_samples; i++) { |
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333 | if(get_bits_left(&alac->gb) <= 0) |
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334 | return -1; |
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335 | for (ch = 0; ch < channels; ch++) |
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336 | alac->extra_bits_buffer[ch][i] = get_bits(&alac->gb, alac->extra_bits); |
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337 | } |
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338 | } |
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339 | for (ch = 0; ch < channels; ch++) { |
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340 | int ret=rice_decompress(alac, alac->predict_error_buffer[ch], |
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341 | alac->nb_samples, bps, |
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342 | rice_history_mult[ch] * alac->rice_history_mult / 4); |
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343 | if(ret<0) |
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344 | return ret; |
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345 | |||
346 | /* adaptive FIR filter */ |
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347 | if (prediction_type[ch] == 15) { |
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348 | /* Prediction type 15 runs the adaptive FIR twice. |
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349 | * The first pass uses the special-case coef_num = 31, while |
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350 | * the second pass uses the coefs from the bitstream. |
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351 | * |
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352 | * However, this prediction type is not currently used by the |
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353 | * reference encoder. |
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354 | */ |
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355 | lpc_prediction(alac->predict_error_buffer[ch], |
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356 | alac->predict_error_buffer[ch], |
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357 | alac->nb_samples, bps, NULL, 31, 0); |
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358 | } else if (prediction_type[ch] > 0) { |
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359 | av_log(avctx, AV_LOG_WARNING, "unknown prediction type: %i\n", |
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360 | prediction_type[ch]); |
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361 | } |
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362 | lpc_prediction(alac->predict_error_buffer[ch], |
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363 | alac->output_samples_buffer[ch], alac->nb_samples, |
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364 | bps, lpc_coefs[ch], lpc_order[ch], lpc_quant[ch]); |
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365 | } |
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366 | } else { |
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367 | /* not compressed, easy case */ |
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368 | for (i = 0; i < alac->nb_samples; i++) { |
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369 | if(get_bits_left(&alac->gb) <= 0) |
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370 | return -1; |
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371 | for (ch = 0; ch < channels; ch++) { |
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372 | alac->output_samples_buffer[ch][i] = |
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373 | get_sbits_long(&alac->gb, alac->sample_size); |
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374 | } |
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375 | } |
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376 | alac->extra_bits = 0; |
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377 | decorr_shift = 0; |
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378 | decorr_left_weight = 0; |
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379 | } |
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380 | |||
381 | if (channels == 2 && decorr_left_weight) { |
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382 | decorrelate_stereo(alac->output_samples_buffer, alac->nb_samples, |
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383 | decorr_shift, decorr_left_weight); |
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384 | } |
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385 | |||
386 | if (alac->extra_bits) { |
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387 | append_extra_bits(alac->output_samples_buffer, alac->extra_bits_buffer, |
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388 | alac->extra_bits, channels, alac->nb_samples); |
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389 | } |
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390 | |||
391 | if(av_sample_fmt_is_planar(avctx->sample_fmt)) { |
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392 | switch(alac->sample_size) { |
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393 | case 16: { |
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394 | for (ch = 0; ch < channels; ch++) { |
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395 | int16_t *outbuffer = (int16_t *)frame->extended_data[ch_index + ch]; |
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396 | for (i = 0; i < alac->nb_samples; i++) |
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397 | *outbuffer++ = alac->output_samples_buffer[ch][i]; |
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398 | }} |
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399 | break; |
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400 | case 24: { |
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401 | for (ch = 0; ch < channels; ch++) { |
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402 | for (i = 0; i < alac->nb_samples; i++) |
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403 | alac->output_samples_buffer[ch][i] <<= 8; |
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404 | }} |
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405 | break; |
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406 | } |
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407 | }else{ |
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408 | switch(alac->sample_size) { |
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409 | case 16: { |
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410 | int16_t *outbuffer = ((int16_t *)frame->extended_data[0]) + ch_index; |
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411 | for (i = 0; i < alac->nb_samples; i++) { |
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412 | for (ch = 0; ch < channels; ch++) |
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413 | *outbuffer++ = alac->output_samples_buffer[ch][i]; |
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414 | outbuffer += alac->channels - channels; |
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415 | } |
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416 | } |
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417 | break; |
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418 | case 24: { |
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419 | int32_t *outbuffer = ((int32_t *)frame->extended_data[0]) + ch_index; |
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420 | for (i = 0; i < alac->nb_samples; i++) { |
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421 | for (ch = 0; ch < channels; ch++) |
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422 | *outbuffer++ = alac->output_samples_buffer[ch][i] << 8; |
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423 | outbuffer += alac->channels - channels; |
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424 | } |
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425 | } |
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426 | break; |
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427 | case 32: { |
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428 | int32_t *outbuffer = ((int32_t *)frame->extended_data[0]) + ch_index; |
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429 | for (i = 0; i < alac->nb_samples; i++) { |
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430 | for (ch = 0; ch < channels; ch++) |
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431 | *outbuffer++ = alac->output_samples_buffer[ch][i]; |
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432 | outbuffer += alac->channels - channels; |
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433 | } |
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434 | } |
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435 | break; |
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436 | } |
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437 | } |
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438 | |||
439 | return 0; |
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440 | } |
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441 | |||
442 | static int alac_decode_frame(AVCodecContext *avctx, void *data, |
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443 | int *got_frame_ptr, AVPacket *avpkt) |
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444 | { |
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445 | ALACContext *alac = avctx->priv_data; |
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446 | AVFrame *frame = data; |
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447 | enum AlacRawDataBlockType element; |
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448 | int channels; |
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449 | int ch, ret, got_end; |
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450 | |||
451 | if ((ret = init_get_bits8(&alac->gb, avpkt->data, avpkt->size)) < 0) |
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452 | return ret; |
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453 | |||
454 | got_end = 0; |
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455 | alac->nb_samples = 0; |
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456 | ch = 0; |
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457 | while (get_bits_left(&alac->gb) >= 3) { |
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458 | element = get_bits(&alac->gb, 3); |
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459 | if (element == TYPE_END) { |
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460 | got_end = 1; |
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461 | break; |
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462 | } |
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463 | if (element > TYPE_CPE && element != TYPE_LFE) { |
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464 | av_log(avctx, AV_LOG_ERROR, "syntax element unsupported: %d\n", element); |
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465 | return AVERROR_PATCHWELCOME; |
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466 | } |
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467 | |||
468 | channels = (element == TYPE_CPE) ? 2 : 1; |
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469 | if (ch + channels > alac->channels || |
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470 | ff_alac_channel_layout_offsets[alac->channels - 1][ch] + channels > alac->channels) { |
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471 | av_log(avctx, AV_LOG_ERROR, "invalid element channel count\n"); |
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472 | return AVERROR_INVALIDDATA; |
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473 | } |
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474 | |||
475 | ret = decode_element(avctx, frame, |
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476 | ff_alac_channel_layout_offsets[alac->channels - 1][ch], |
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477 | channels); |
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478 | if (ret < 0 && get_bits_left(&alac->gb)) |
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479 | return ret; |
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480 | |||
481 | ch += channels; |
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482 | } |
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483 | if (!got_end) { |
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484 | av_log(avctx, AV_LOG_ERROR, "no end tag found. incomplete packet.\n"); |
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485 | return AVERROR_INVALIDDATA; |
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486 | } |
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487 | |||
488 | if (avpkt->size * 8 - get_bits_count(&alac->gb) > 8) { |
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489 | av_log(avctx, AV_LOG_ERROR, "Error : %d bits left\n", |
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490 | avpkt->size * 8 - get_bits_count(&alac->gb)); |
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491 | } |
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492 | |||
493 | *got_frame_ptr = 1; |
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494 | |||
495 | return avpkt->size; |
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496 | } |
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497 | |||
498 | static av_cold int alac_decode_close(AVCodecContext *avctx) |
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499 | { |
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500 | ALACContext *alac = avctx->priv_data; |
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501 | |||
502 | int ch; |
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503 | for (ch = 0; ch < FFMIN(alac->channels, 2); ch++) { |
||
504 | av_freep(&alac->predict_error_buffer[ch]); |
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505 | if (!alac->direct_output) |
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506 | av_freep(&alac->output_samples_buffer[ch]); |
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507 | av_freep(&alac->extra_bits_buffer[ch]); |
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508 | } |
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509 | |||
510 | return 0; |
||
511 | } |
||
512 | |||
513 | static int allocate_buffers(ALACContext *alac) |
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514 | { |
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515 | int ch; |
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516 | int buf_size = alac->max_samples_per_frame * sizeof(int32_t); |
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517 | |||
518 | for (ch = 0; ch < FFMIN(alac->channels, 2); ch++) { |
||
519 | FF_ALLOC_OR_GOTO(alac->avctx, alac->predict_error_buffer[ch], |
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520 | buf_size, buf_alloc_fail); |
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521 | |||
522 | alac->direct_output = alac->sample_size > 16 && av_sample_fmt_is_planar(alac->avctx->sample_fmt); |
||
523 | if (!alac->direct_output) { |
||
524 | FF_ALLOC_OR_GOTO(alac->avctx, alac->output_samples_buffer[ch], |
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525 | buf_size, buf_alloc_fail); |
||
526 | } |
||
527 | |||
528 | FF_ALLOC_OR_GOTO(alac->avctx, alac->extra_bits_buffer[ch], |
||
529 | buf_size, buf_alloc_fail); |
||
530 | } |
||
531 | return 0; |
||
532 | buf_alloc_fail: |
||
533 | alac_decode_close(alac->avctx); |
||
534 | return AVERROR(ENOMEM); |
||
535 | } |
||
536 | |||
537 | static int alac_set_info(ALACContext *alac) |
||
538 | { |
||
539 | GetByteContext gb; |
||
540 | |||
541 | bytestream2_init(&gb, alac->avctx->extradata, |
||
542 | alac->avctx->extradata_size); |
||
543 | |||
544 | bytestream2_skipu(&gb, 12); // size:4, alac:4, version:4 |
||
545 | |||
546 | alac->max_samples_per_frame = bytestream2_get_be32u(&gb); |
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547 | if (!alac->max_samples_per_frame || |
||
548 | alac->max_samples_per_frame > INT_MAX / sizeof(int32_t)) { |
||
549 | av_log(alac->avctx, AV_LOG_ERROR, "max samples per frame invalid: %u\n", |
||
550 | alac->max_samples_per_frame); |
||
551 | return AVERROR_INVALIDDATA; |
||
552 | } |
||
553 | bytestream2_skipu(&gb, 1); // compatible version |
||
554 | alac->sample_size = bytestream2_get_byteu(&gb); |
||
555 | alac->rice_history_mult = bytestream2_get_byteu(&gb); |
||
556 | alac->rice_initial_history = bytestream2_get_byteu(&gb); |
||
557 | alac->rice_limit = bytestream2_get_byteu(&gb); |
||
558 | alac->channels = bytestream2_get_byteu(&gb); |
||
559 | bytestream2_get_be16u(&gb); // maxRun |
||
560 | bytestream2_get_be32u(&gb); // max coded frame size |
||
561 | bytestream2_get_be32u(&gb); // average bitrate |
||
562 | bytestream2_get_be32u(&gb); // samplerate |
||
563 | |||
564 | return 0; |
||
565 | } |
||
566 | |||
567 | static av_cold int alac_decode_init(AVCodecContext * avctx) |
||
568 | { |
||
569 | int ret; |
||
570 | int req_packed; |
||
571 | ALACContext *alac = avctx->priv_data; |
||
572 | alac->avctx = avctx; |
||
573 | |||
574 | /* initialize from the extradata */ |
||
575 | if (alac->avctx->extradata_size < ALAC_EXTRADATA_SIZE) { |
||
576 | av_log(avctx, AV_LOG_ERROR, "extradata is too small\n"); |
||
577 | return AVERROR_INVALIDDATA; |
||
578 | } |
||
579 | if (alac_set_info(alac)) { |
||
580 | av_log(avctx, AV_LOG_ERROR, "set_info failed\n"); |
||
581 | return -1; |
||
582 | } |
||
583 | |||
584 | req_packed = LIBAVCODEC_VERSION_MAJOR < 55 && !av_sample_fmt_is_planar(avctx->request_sample_fmt); |
||
585 | switch (alac->sample_size) { |
||
586 | case 16: avctx->sample_fmt = req_packed ? AV_SAMPLE_FMT_S16 : AV_SAMPLE_FMT_S16P; |
||
587 | break; |
||
588 | case 24: |
||
589 | case 32: avctx->sample_fmt = req_packed ? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S32P; |
||
590 | break; |
||
591 | default: avpriv_request_sample(avctx, "Sample depth %d", alac->sample_size); |
||
592 | return AVERROR_PATCHWELCOME; |
||
593 | } |
||
594 | avctx->bits_per_raw_sample = alac->sample_size; |
||
595 | |||
596 | if (alac->channels < 1) { |
||
597 | av_log(avctx, AV_LOG_WARNING, "Invalid channel count\n"); |
||
598 | alac->channels = avctx->channels; |
||
599 | } else { |
||
600 | if (alac->channels > ALAC_MAX_CHANNELS) |
||
601 | alac->channels = avctx->channels; |
||
602 | else |
||
603 | avctx->channels = alac->channels; |
||
604 | } |
||
605 | if (avctx->channels > ALAC_MAX_CHANNELS || avctx->channels <= 0 ) { |
||
606 | av_log(avctx, AV_LOG_ERROR, "Unsupported channel count: %d\n", |
||
607 | avctx->channels); |
||
608 | return AVERROR_PATCHWELCOME; |
||
609 | } |
||
610 | avctx->channel_layout = ff_alac_channel_layouts[alac->channels - 1]; |
||
611 | |||
612 | if ((ret = allocate_buffers(alac)) < 0) { |
||
613 | av_log(avctx, AV_LOG_ERROR, "Error allocating buffers\n"); |
||
614 | return ret; |
||
615 | } |
||
616 | |||
617 | return 0; |
||
618 | } |
||
619 | |||
620 | static int init_thread_copy(AVCodecContext *avctx) |
||
621 | { |
||
622 | ALACContext *alac = avctx->priv_data; |
||
623 | alac->avctx = avctx; |
||
624 | return allocate_buffers(alac); |
||
625 | } |
||
626 | |||
627 | AVCodec ff_alac_decoder = { |
||
628 | .name = "alac", |
||
629 | .long_name = NULL_IF_CONFIG_SMALL("ALAC (Apple Lossless Audio Codec)"), |
||
630 | .type = AVMEDIA_TYPE_AUDIO, |
||
631 | .id = AV_CODEC_ID_ALAC, |
||
632 | .priv_data_size = sizeof(ALACContext), |
||
633 | .init = alac_decode_init, |
||
634 | .close = alac_decode_close, |
||
635 | .decode = alac_decode_frame, |
||
636 | .init_thread_copy = ONLY_IF_THREADS_ENABLED(init_thread_copy), |
||
637 | .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS, |
||
638 | };>=>>>>>>>>>>><>>>>>=><=>>>>>>=>>0) |