Add configuration options section to help output.
[libav.git] / libavcodec / flacdec.c
CommitLineData
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1/*
2 * FLAC (Free Lossless Audio Codec) decoder
3 * Copyright (c) 2003 Alex Beregszaszi
4 *
b78e7197
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5 * This file is part of FFmpeg.
6 *
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
9 * License as published by the Free Software Foundation; either
b78e7197 10 * version 2.1 of the License, or (at your option) any later version.
4f52c312 11 *
b78e7197 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
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
b78e7197 18 * License along with FFmpeg; if not, write to the Free Software
5509bffa 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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20 */
21
22/**
8f51144b 23 * @file flacdec.c
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24 * FLAC (Free Lossless Audio Codec) decoder
25 * @author Alex Beregszaszi
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26 *
27 * For more information on the FLAC format, visit:
28 * http://flac.sourceforge.net/
29 *
30 * This decoder can be used in 1 of 2 ways: Either raw FLAC data can be fed
31 * through, starting from the initial 'fLaC' signature; or by passing the
32 * 34-byte streaminfo structure through avctx->extradata[_size] followed
33 * by data starting with the 0xFFF8 marker.
4f52c312 34 */
115329f1 35
ac2570a8 36#include <limits.h>
115329f1 37
75c998a2 38#define ALT_BITSTREAM_READER
245976da 39#include "libavutil/crc.h"
4f52c312 40#include "avcodec.h"
caa336b4 41#include "bitstream.h"
4f52c312 42#include "golomb.h"
9d48410f 43#include "flac.h"
4f52c312 44
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45#undef NDEBUG
46#include <assert.h>
47
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48#define MAX_CHANNELS 8
49#define MAX_BLOCKSIZE 65535
9eda2f94 50#define FLAC_STREAMINFO_SIZE 34
4f52c312 51
9d656110 52enum decorrelation_type {
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53 INDEPENDENT,
54 LEFT_SIDE,
55 RIGHT_SIDE,
56 MID_SIDE,
57};
58
59typedef struct FLACContext {
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60 FLACSTREAMINFO
61
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62 AVCodecContext *avctx;
63 GetBitContext gb;
64
ac2570a8 65 int blocksize/*, last_blocksize*/;
9d48410f 66 int curr_bps;
9d656110 67 enum decorrelation_type decorrelation;
4f52c312 68
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69 int32_t *decoded[MAX_CHANNELS];
70 uint8_t *bitstream;
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71 unsigned int bitstream_size;
72 unsigned int bitstream_index;
f038fe8b 73 unsigned int allocated_bitstream_size;
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74} FLACContext;
75
76#define METADATA_TYPE_STREAMINFO 0
77
cf2baeb3 78static const int sample_rate_table[] =
959e0006
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79{ 0,
80 88200, 176400, 192000,
4f52c312 81 8000, 16000, 22050, 24000, 32000, 44100, 48000, 96000,
115329f1 82 0, 0, 0, 0 };
4f52c312 83
cf2baeb3 84static const int sample_size_table[] =
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85{ 0, 8, 12, 0, 16, 20, 24, 0 };
86
cf2baeb3 87static const int blocksize_table[] = {
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88 0, 192, 576<<0, 576<<1, 576<<2, 576<<3, 0, 0,
89256<<0, 256<<1, 256<<2, 256<<3, 256<<4, 256<<5, 256<<6, 256<<7
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90};
91
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92static int64_t get_utf8(GetBitContext *gb){
93 int64_t val;
94 GET_UTF8(val, get_bits(gb, 8), return -1;)
ac2570a8 95 return val;
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96}
97
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98static void allocate_buffers(FLACContext *s);
99static int metadata_parse(FLACContext *s);
9eda2f94 100
98a6fff9 101static av_cold int flac_decode_init(AVCodecContext * avctx)
4f52c312 102{
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103 FLACContext *s = avctx->priv_data;
104 s->avctx = avctx;
105
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106 if (avctx->extradata_size > 4) {
107 /* initialize based on the demuxer-supplied streamdata header */
17c90b9d 108 if (avctx->extradata_size == FLAC_STREAMINFO_SIZE) {
9482171b 109 ff_flac_parse_streaminfo(avctx, (FLACStreaminfo *)s, avctx->extradata);
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110 allocate_buffers(s);
111 } else {
512b37bb 112 init_get_bits(&s->gb, avctx->extradata, avctx->extradata_size*8);
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113 metadata_parse(s);
114 }
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115 }
116
fd76c37f 117 avctx->sample_fmt = SAMPLE_FMT_S16;
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118 return 0;
119}
120
9482171b 121static void dump_headers(AVCodecContext *avctx, FLACStreaminfo *s)
4f52c312 122{
9482171b 123 av_log(avctx, AV_LOG_DEBUG, " Blocksize: %d .. %d\n", s->min_blocksize, s->max_blocksize);
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124 av_log(avctx, AV_LOG_DEBUG, " Max Framesize: %d\n", s->max_framesize);
125 av_log(avctx, AV_LOG_DEBUG, " Samplerate: %d\n", s->samplerate);
126 av_log(avctx, AV_LOG_DEBUG, " Channels: %d\n", s->channels);
127 av_log(avctx, AV_LOG_DEBUG, " Bits: %d\n", s->bps);
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128}
129
ac2570a8 130static void allocate_buffers(FLACContext *s){
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131 int i;
132
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133 assert(s->max_blocksize);
134
135 if(s->max_framesize == 0 && s->max_blocksize){
136 s->max_framesize= (s->channels * s->bps * s->max_blocksize + 7)/ 8; //FIXME header overhead
137 }
138
139 for (i = 0; i < s->channels; i++)
140 {
141 s->decoded[i] = av_realloc(s->decoded[i], sizeof(int32_t)*s->max_blocksize);
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142 }
143
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144 if(s->allocated_bitstream_size < s->max_framesize)
145 s->bitstream= av_fast_realloc(s->bitstream, &s->allocated_bitstream_size, s->max_framesize);
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146}
147
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148void ff_flac_parse_streaminfo(AVCodecContext *avctx, struct FLACStreaminfo *s,
149 const uint8_t *buffer)
ac2570a8 150{
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151 GetBitContext gb;
152 init_get_bits(&gb, buffer, FLAC_STREAMINFO_SIZE*8);
153
4f52c312 154 /* mandatory streaminfo */
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155 s->min_blocksize = get_bits(&gb, 16);
156 s->max_blocksize = get_bits(&gb, 16);
4f52c312 157
a128cc91
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158 skip_bits(&gb, 24); /* skip min frame size */
159 s->max_framesize = get_bits_long(&gb, 24);
115329f1 160
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161 s->samplerate = get_bits_long(&gb, 20);
162 s->channels = get_bits(&gb, 3) + 1;
163 s->bps = get_bits(&gb, 5) + 1;
115329f1 164
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165 avctx->channels = s->channels;
166 avctx->sample_rate = s->samplerate;
4f52c312 167
a128cc91 168 skip_bits(&gb, 36); /* total num of samples */
115329f1 169
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170 skip_bits(&gb, 64); /* md5 sum */
171 skip_bits(&gb, 64); /* md5 sum */
115329f1 172
4bc07e78 173 dump_headers(avctx, s);
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174}
175
176/**
177 * Parse a list of metadata blocks. This list of blocks must begin with
178 * the fLaC marker.
179 * @param s the flac decoding context containing the gb bit reader used to
180 * parse metadata
181 * @return 1 if some metadata was read, 0 if no fLaC marker was found
182 */
183static int metadata_parse(FLACContext *s)
184{
185 int i, metadata_last, metadata_type, metadata_size, streaminfo_updated=0;
e0168e3b 186 int initial_pos= get_bits_count(&s->gb);
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187
188 if (show_bits_long(&s->gb, 32) == MKBETAG('f','L','a','C')) {
189 skip_bits(&s->gb, 32);
190
17c90b9d 191 do {
5fc32c27 192 metadata_last = get_bits1(&s->gb);
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193 metadata_type = get_bits(&s->gb, 7);
194 metadata_size = get_bits_long(&s->gb, 24);
195
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196 if(get_bits_count(&s->gb) + 8*metadata_size > s->gb.size_in_bits){
197 skip_bits_long(&s->gb, initial_pos - get_bits_count(&s->gb));
198 break;
199 }
200
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201 if (metadata_size) {
202 switch (metadata_type) {
203 case METADATA_TYPE_STREAMINFO:
9482171b 204 ff_flac_parse_streaminfo(s->avctx, (FLACStreaminfo *)s, s->gb.buffer+get_bits_count(&s->gb)/8);
17c90b9d 205 streaminfo_updated = 1;
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206
207 default:
208 for (i=0; i<metadata_size; i++)
209 skip_bits(&s->gb, 8);
210 }
211 }
212 } while (!metadata_last);
213
214 if (streaminfo_updated)
215 allocate_buffers(s);
216 return 1;
217 }
218 return 0;
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219}
220
221static int decode_residuals(FLACContext *s, int channel, int pred_order)
222{
223 int i, tmp, partition, method_type, rice_order;
224 int sample = 0, samples;
225
226 method_type = get_bits(&s->gb, 2);
e471443a 227 if (method_type > 1){
5305f40b 228 av_log(s->avctx, AV_LOG_ERROR, "illegal residual coding method %d\n", method_type);
4f52c312 229 return -1;
ac2570a8 230 }
115329f1 231
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232 rice_order = get_bits(&s->gb, 4);
233
ac2570a8 234 samples= s->blocksize >> rice_order;
5484dad7
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235 if (pred_order > samples) {
236 av_log(s->avctx, AV_LOG_ERROR, "invalid predictor order: %i > %i\n", pred_order, samples);
237 return -1;
238 }
4f52c312 239
115329f1 240 sample=
ac2570a8 241 i= pred_order;
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242 for (partition = 0; partition < (1 << rice_order); partition++)
243 {
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244 tmp = get_bits(&s->gb, method_type == 0 ? 4 : 5);
245 if (tmp == (method_type == 0 ? 15 : 31))
4f52c312 246 {
4f52c312 247 tmp = get_bits(&s->gb, 5);
4f52c312 248 for (; i < samples; i++, sample++)
4fd12598 249 s->decoded[channel][sample] = get_sbits(&s->gb, tmp);
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250 }
251 else
252 {
ac2570a8 253 for (; i < samples; i++, sample++){
4fd12598 254 s->decoded[channel][sample] = get_sr_golomb_flac(&s->gb, tmp, INT_MAX, 0);
ac2570a8 255 }
4f52c312 256 }
ac2570a8 257 i= 0;
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258 }
259
4f52c312 260 return 0;
115329f1 261}
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262
263static int decode_subframe_fixed(FLACContext *s, int channel, int pred_order)
264{
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265 const int blocksize = s->blocksize;
266 int32_t *decoded = s->decoded[channel];
267 int a, b, c, d, i;
115329f1 268
4f52c312 269 /* warm up samples */
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270 for (i = 0; i < pred_order; i++)
271 {
08965b22 272 decoded[i] = get_sbits(&s->gb, s->curr_bps);
4f52c312 273 }
115329f1 274
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275 if (decode_residuals(s, channel, pred_order) < 0)
276 return -1;
277
0ec7b71d 278 if(pred_order > 0)
1f4fa6a4 279 a = decoded[pred_order-1];
0ec7b71d 280 if(pred_order > 1)
1f4fa6a4 281 b = a - decoded[pred_order-2];
0ec7b71d 282 if(pred_order > 2)
1f4fa6a4 283 c = b - decoded[pred_order-2] + decoded[pred_order-3];
0ec7b71d 284 if(pred_order > 3)
1f4fa6a4 285 d = c - decoded[pred_order-2] + 2*decoded[pred_order-3] - decoded[pred_order-4];
08965b22 286
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287 switch(pred_order)
288 {
289 case 0:
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290 break;
291 case 1:
08965b22
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292 for (i = pred_order; i < blocksize; i++)
293 decoded[i] = a += decoded[i];
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294 break;
295 case 2:
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296 for (i = pred_order; i < blocksize; i++)
297 decoded[i] = a += b += decoded[i];
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298 break;
299 case 3:
08965b22
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300 for (i = pred_order; i < blocksize; i++)
301 decoded[i] = a += b += c += decoded[i];
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302 break;
303 case 4:
08965b22
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304 for (i = pred_order; i < blocksize; i++)
305 decoded[i] = a += b += c += d += decoded[i];
4f52c312 306 break;
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307 default:
308 av_log(s->avctx, AV_LOG_ERROR, "illegal pred order %d\n", pred_order);
309 return -1;
4f52c312 310 }
ac2570a8 311
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312 return 0;
313}
314
315static int decode_subframe_lpc(FLACContext *s, int channel, int pred_order)
316{
0187178e 317 int i, j;
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318 int coeff_prec, qlevel;
319 int coeffs[pred_order];
d1a5c421 320 int32_t *decoded = s->decoded[channel];
115329f1 321
4f52c312 322 /* warm up samples */
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323 for (i = 0; i < pred_order; i++)
324 {
d1a5c421 325 decoded[i] = get_sbits(&s->gb, s->curr_bps);
4f52c312 326 }
115329f1 327
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328 coeff_prec = get_bits(&s->gb, 4) + 1;
329 if (coeff_prec == 16)
330 {
5305f40b 331 av_log(s->avctx, AV_LOG_ERROR, "invalid coeff precision\n");
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332 return -1;
333 }
ac2570a8 334 qlevel = get_sbits(&s->gb, 5);
9d656110 335 if(qlevel < 0){
5305f40b 336 av_log(s->avctx, AV_LOG_ERROR, "qlevel %d not supported, maybe buggy stream\n", qlevel);
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337 return -1;
338 }
339
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340 for (i = 0; i < pred_order; i++)
341 {
ac2570a8 342 coeffs[i] = get_sbits(&s->gb, coeff_prec);
4f52c312 343 }
115329f1 344
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345 if (decode_residuals(s, channel, pred_order) < 0)
346 return -1;
347
0187178e
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348 if (s->bps > 16) {
349 int64_t sum;
350 for (i = pred_order; i < s->blocksize; i++)
351 {
352 sum = 0;
353 for (j = 0; j < pred_order; j++)
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354 sum += (int64_t)coeffs[j] * decoded[i-j-1];
355 decoded[i] += sum >> qlevel;
0187178e
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356 }
357 } else {
bd49d4fd 358 for (i = pred_order; i < s->blocksize-1; i += 2)
0187178e 359 {
d1a5c421
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360 int c;
361 int d = decoded[i-pred_order];
362 int s0 = 0, s1 = 0;
bd49d4fd
LM
363 for (j = pred_order-1; j > 0; j--)
364 {
d1a5c421 365 c = coeffs[j];
bd49d4fd 366 s0 += c*d;
d1a5c421
LM
367 d = decoded[i-j];
368 s1 += c*d;
bd49d4fd 369 }
d1a5c421
LM
370 c = coeffs[0];
371 s0 += c*d;
372 d = decoded[i] += s0 >> qlevel;
373 s1 += c*d;
374 decoded[i+1] += s1 >> qlevel;
bd49d4fd
LM
375 }
376 if (i < s->blocksize)
377 {
378 int sum = 0;
0187178e 379 for (j = 0; j < pred_order; j++)
d1a5c421
LM
380 sum += coeffs[j] * decoded[i-j-1];
381 decoded[i] += sum >> qlevel;
0187178e 382 }
4f52c312 383 }
115329f1 384
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385 return 0;
386}
387
388static inline int decode_subframe(FLACContext *s, int channel)
389{
390 int type, wasted = 0;
391 int i, tmp;
115329f1 392
4f52c312 393 s->curr_bps = s->bps;
ac2570a8 394 if(channel == 0){
9d656110 395 if(s->decorrelation == RIGHT_SIDE)
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396 s->curr_bps++;
397 }else{
9d656110 398 if(s->decorrelation == LEFT_SIDE || s->decorrelation == MID_SIDE)
ac2570a8
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399 s->curr_bps++;
400 }
401
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402 if (get_bits1(&s->gb))
403 {
1cef211d 404 av_log(s->avctx, AV_LOG_ERROR, "invalid subframe padding\n");
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405 return -1;
406 }
407 type = get_bits(&s->gb, 6);
c5706efd 408
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409 if (get_bits1(&s->gb))
410 {
411 wasted = 1;
412 while (!get_bits1(&s->gb))
413 wasted++;
414 s->curr_bps -= wasted;
415 }
c5706efd 416
ac2570a8 417//FIXME use av_log2 for types
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418 if (type == 0)
419 {
ac2570a8 420 tmp = get_sbits(&s->gb, s->curr_bps);
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421 for (i = 0; i < s->blocksize; i++)
422 s->decoded[channel][i] = tmp;
423 }
424 else if (type == 1)
425 {
4f52c312 426 for (i = 0; i < s->blocksize; i++)
ac2570a8 427 s->decoded[channel][i] = get_sbits(&s->gb, s->curr_bps);
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428 }
429 else if ((type >= 8) && (type <= 12))
430 {
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431 if (decode_subframe_fixed(s, channel, type & ~0x8) < 0)
432 return -1;
433 }
434 else if (type >= 32)
435 {
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436 if (decode_subframe_lpc(s, channel, (type & ~0x20)+1) < 0)
437 return -1;
438 }
439 else
440 {
1cef211d 441 av_log(s->avctx, AV_LOG_ERROR, "invalid coding type\n");
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442 return -1;
443 }
115329f1 444
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445 if (wasted)
446 {
447 int i;
448 for (i = 0; i < s->blocksize; i++)
449 s->decoded[channel][i] <<= wasted;
450 }
451
452 return 0;
453}
454
ac66834c 455static int decode_frame(FLACContext *s, int alloc_data_size)
4f52c312 456{
9d656110 457 int blocksize_code, sample_rate_code, sample_size_code, assignment, i, crc8;
0496a034 458 int decorrelation, bps, blocksize, samplerate;
115329f1 459
4f52c312 460 blocksize_code = get_bits(&s->gb, 4);
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461
462 sample_rate_code = get_bits(&s->gb, 4);
115329f1 463
4f52c312 464 assignment = get_bits(&s->gb, 4); /* channel assignment */
0496a034
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465 if (assignment < 8 && s->channels == assignment+1)
466 decorrelation = INDEPENDENT;
467 else if (assignment >=8 && assignment < 11 && s->channels == 2)
468 decorrelation = LEFT_SIDE + assignment - 8;
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469 else
470 {
1cef211d 471 av_log(s->avctx, AV_LOG_ERROR, "unsupported channel assignment %d (channels=%d)\n", assignment, s->channels);
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472 return -1;
473 }
115329f1 474
4f52c312 475 sample_size_code = get_bits(&s->gb, 3);
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476 if(sample_size_code == 0)
477 bps= s->bps;
478 else if((sample_size_code != 3) && (sample_size_code != 7))
479 bps = sample_size_table[sample_size_code];
115329f1 480 else
4f52c312 481 {
1cef211d 482 av_log(s->avctx, AV_LOG_ERROR, "invalid sample size code (%d)\n", sample_size_code);
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483 return -1;
484 }
485
486 if (get_bits1(&s->gb))
487 {
1cef211d 488 av_log(s->avctx, AV_LOG_ERROR, "broken stream, invalid padding\n");
0496a034 489 return -1;
4f52c312 490 }
115329f1 491
0496a034
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492 if(get_utf8(&s->gb) < 0){
493 av_log(s->avctx, AV_LOG_ERROR, "utf8 fscked\n");
494 return -1;
495 }
115329f1 496
ac2570a8 497 if (blocksize_code == 0)
0496a034 498 blocksize = s->min_blocksize;
ac2570a8 499 else if (blocksize_code == 6)
0496a034 500 blocksize = get_bits(&s->gb, 8)+1;
ac2570a8 501 else if (blocksize_code == 7)
0496a034 502 blocksize = get_bits(&s->gb, 16)+1;
115329f1 503 else
0496a034 504 blocksize = blocksize_table[blocksize_code];
4f52c312 505
0496a034
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506 if(blocksize > s->max_blocksize){
507 av_log(s->avctx, AV_LOG_ERROR, "blocksize %d > %d\n", blocksize, s->max_blocksize);
ac2570a8
MN
508 return -1;
509 }
510
ac66834c
MN
511 if(blocksize * s->channels * sizeof(int16_t) > alloc_data_size)
512 return -1;
513
ac2570a8 514 if (sample_rate_code == 0){
0496a034 515 samplerate= s->samplerate;
959e0006 516 }else if (sample_rate_code < 12)
0496a034 517 samplerate = sample_rate_table[sample_rate_code];
ac2570a8 518 else if (sample_rate_code == 12)
0496a034 519 samplerate = get_bits(&s->gb, 8) * 1000;
ac2570a8 520 else if (sample_rate_code == 13)
0496a034 521 samplerate = get_bits(&s->gb, 16);
ac2570a8 522 else if (sample_rate_code == 14)
0496a034 523 samplerate = get_bits(&s->gb, 16) * 10;
ac2570a8
MN
524 else{
525 av_log(s->avctx, AV_LOG_ERROR, "illegal sample rate code %d\n", sample_rate_code);
526 return -1;
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527 }
528
9d656110 529 skip_bits(&s->gb, 8);
3abe5fbd
AJ
530 crc8 = av_crc(av_crc_get_table(AV_CRC_8_ATM), 0,
531 s->gb.buffer, get_bits_count(&s->gb)/8);
9d656110 532 if(crc8){
160d679c 533 av_log(s->avctx, AV_LOG_ERROR, "header crc mismatch crc=%2X\n", crc8);
9d656110
MN
534 return -1;
535 }
115329f1 536
0496a034
MN
537 s->blocksize = blocksize;
538 s->samplerate = samplerate;
539 s->bps = bps;
540 s->decorrelation= decorrelation;
4f52c312 541
9482171b 542// dump_headers(s->avctx, (FLACStreaminfo *)s);
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543
544 /* subframes */
545 for (i = 0; i < s->channels; i++)
546 {
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547 if (decode_subframe(s, i) < 0)
548 return -1;
549 }
115329f1 550
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551 align_get_bits(&s->gb);
552
553 /* frame footer */
554 skip_bits(&s->gb, 16); /* data crc */
555
556 return 0;
557}
558
559static int flac_decode_frame(AVCodecContext *avctx,
560 void *data, int *data_size,
1545c5e5 561 const uint8_t *buf, int buf_size)
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562{
563 FLACContext *s = avctx->priv_data;
3f1899a8
MM
564 int tmp = 0, i, j = 0, input_buf_size = 0;
565 int16_t *samples = data;
ac66834c
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566 int alloc_data_size= *data_size;
567
568 *data_size=0;
4f52c312 569
ac2570a8 570 if(s->max_framesize == 0){
d3ce0792 571 s->max_framesize= FFMAX(4, buf_size); // should hopefully be enough for the first header
ac2570a8
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572 s->bitstream= av_fast_realloc(s->bitstream, &s->allocated_bitstream_size, s->max_framesize);
573 }
574
575 if(1 && s->max_framesize){//FIXME truncated
e0168e3b
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576 if(s->bitstream_size < 4 || AV_RL32(s->bitstream) != MKTAG('f','L','a','C'))
577 buf_size= FFMIN(buf_size, s->max_framesize - FFMIN(s->bitstream_size, s->max_framesize));
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578 input_buf_size= buf_size;
579
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580 if(s->bitstream_size + buf_size < buf_size || s->bitstream_index + s->bitstream_size + buf_size < s->bitstream_index)
581 return -1;
582
583 if(s->allocated_bitstream_size < s->bitstream_size + buf_size)
584 s->bitstream= av_fast_realloc(s->bitstream, &s->allocated_bitstream_size, s->bitstream_size + buf_size);
585
ac2570a8 586 if(s->bitstream_index + s->bitstream_size + buf_size > s->allocated_bitstream_size){
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587 memmove(s->bitstream, &s->bitstream[s->bitstream_index], s->bitstream_size);
588 s->bitstream_index=0;
589 }
590 memcpy(&s->bitstream[s->bitstream_index + s->bitstream_size], buf, buf_size);
591 buf= &s->bitstream[s->bitstream_index];
592 buf_size += s->bitstream_size;
593 s->bitstream_size= buf_size;
115329f1 594
4c453ddb 595 if(buf_size < s->max_framesize && input_buf_size){
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596 return input_buf_size;
597 }
598 }
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599
600 init_get_bits(&s->gb, buf, buf_size*8);
115329f1 601
2b4b8c82
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602 if(metadata_parse(s))
603 goto end;
604
13de8a08
JR
605 tmp = show_bits(&s->gb, 16);
606 if((tmp & 0xFFFE) != 0xFFF8){
607 av_log(s->avctx, AV_LOG_ERROR, "FRAME HEADER not here\n");
608 while(get_bits_count(&s->gb)/8+2 < buf_size && (show_bits(&s->gb, 16) & 0xFFFE) != 0xFFF8)
609 skip_bits(&s->gb, 8);
610 goto end; // we may not have enough bits left to decode a frame, so try next time
611 }
612 skip_bits(&s->gb, 16);
613 if (decode_frame(s, alloc_data_size) < 0){
614 av_log(s->avctx, AV_LOG_ERROR, "decode_frame() failed\n");
615 s->bitstream_size=0;
616 s->bitstream_index=0;
617 return -1;
618 }
ac2570a8 619
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620#define DECORRELATE(left, right)\
621 assert(s->channels == 2);\
622 for (i = 0; i < s->blocksize; i++)\
623 {\
624 int a= s->decoded[0][i];\
625 int b= s->decoded[1][i];\
71fd1225
BF
626 *samples++ = ((left) << (24 - s->bps)) >> 8;\
627 *samples++ = ((right) << (24 - s->bps)) >> 8;\
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628 }\
629 break;
630
9d656110 631 switch(s->decorrelation)
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632 {
633 case INDEPENDENT:
ac2570a8 634 for (j = 0; j < s->blocksize; j++)
4f52c312 635 {
ac2570a8 636 for (i = 0; i < s->channels; i++)
71fd1225 637 *samples++ = (s->decoded[i][j] << (24 - s->bps)) >> 8;
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638 }
639 break;
640 case LEFT_SIDE:
c448303d 641 DECORRELATE(a,a-b)
4f52c312 642 case RIGHT_SIDE:
c448303d 643 DECORRELATE(a+b,b)
4f52c312 644 case MID_SIDE:
c448303d 645 DECORRELATE( (a-=b>>1) + b, a)
4f52c312 646 }
4f52c312 647
ac2570a8 648 *data_size = (int8_t *)samples - (int8_t *)data;
4f52c312 649
ac2570a8 650end:
cea96420 651 i= (get_bits_count(&s->gb)+7)/8;
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652 if(i > buf_size){
653 av_log(s->avctx, AV_LOG_ERROR, "overread: %d\n", i - buf_size);
9d656110
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654 s->bitstream_size=0;
655 s->bitstream_index=0;
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656 return -1;
657 }
4f52c312 658
ac2570a8
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659 if(s->bitstream_size){
660 s->bitstream_index += i;
661 s->bitstream_size -= i;
662 return input_buf_size;
115329f1 663 }else
ac2570a8 664 return i;
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665}
666
98a6fff9 667static av_cold int flac_decode_close(AVCodecContext *avctx)
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668{
669 FLACContext *s = avctx->priv_data;
670 int i;
115329f1 671
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672 for (i = 0; i < s->channels; i++)
673 {
ac2570a8 674 av_freep(&s->decoded[i]);
4f52c312 675 }
ac2570a8 676 av_freep(&s->bitstream);
115329f1 677
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678 return 0;
679}
680
1e31d32c 681static void flac_flush(AVCodecContext *avctx){
1e31d32c
MN
682 FLACContext *s = avctx->priv_data;
683
684 s->bitstream_size=
685 s->bitstream_index= 0;
686}
687
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688AVCodec flac_decoder = {
689 "flac",
690 CODEC_TYPE_AUDIO,
691 CODEC_ID_FLAC,
692 sizeof(FLACContext),
693 flac_decode_init,
694 NULL,
695 flac_decode_close,
696 flac_decode_frame,
4c453ddb 697 CODEC_CAP_DELAY,
115329f1 698 .flush= flac_flush,
fe4bf374 699 .long_name= NULL_IF_CONFIG_SMALL("FLAC (Free Lossless Audio Codec)"),
4f52c312 700};