added support for the elusive AVI palette change chunk, courtesy of
[libav.git] / libavformat / avidec.c
CommitLineData
de6d9b64
FB
1/*
2 * AVI decoder.
19720f15 3 * Copyright (c) 2001 Fabrice Bellard.
de6d9b64 4 *
19720f15
FB
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
de6d9b64 9 *
19720f15 10 * This library is distributed in the hope that it will be useful,
de6d9b64 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19720f15
FB
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
de6d9b64 14 *
19720f15
FB
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
de6d9b64 18 */
de6d9b64
FB
19#include "avformat.h"
20#include "avi.h"
7458ccbb 21#include "dv.h"
de6d9b64
FB
22
23//#define DEBUG
155e9ee9
FB
24//#define DEBUG_SEEK
25
26typedef struct AVIIndexEntry {
27 unsigned int flags;
28 unsigned int pos;
29 unsigned int cum_len; /* sum of all lengths before this packet */
30} AVIIndexEntry;
31
32typedef struct AVIStream {
33 AVIIndexEntry *index_entries;
34 int nb_index_entries;
35 int index_entries_allocated_size;
36 int frame_offset; /* current frame (video) or byte (audio) counter
37 (used to compute the pts) */
38 int scale;
39 int rate;
40 int sample_size; /* audio only data */
1fa3d65d 41 int start;
155e9ee9
FB
42
43 int new_frame_offset; /* temporary storage (used during seek) */
44 int cum_len; /* temporary storage (used during seek) */
d2c5f0a4
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45
46 int prefix; ///< normally 'd'<<8 + 'c' or 'w'<<8 + 'b'
47 int prefix_count;
155e9ee9 48} AVIStream;
de6d9b64
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49
50typedef struct {
7458ccbb
RS
51 int64_t riff_end;
52 int64_t movi_end;
de6d9b64 53 offset_t movi_list;
155e9ee9 54 int index_loaded;
8f9298f8 55 int is_odml;
ddaae6a9 56 DVDemuxContext* dv_demux;
de6d9b64
FB
57} AVIContext;
58
42feef6b
MN
59static int avi_load_index(AVFormatContext *s);
60
de6d9b64 61#ifdef DEBUG
1101abfe 62static void print_tag(const char *str, unsigned int tag, int size)
de6d9b64
FB
63{
64 printf("%s: tag=%c%c%c%c size=0x%x\n",
65 str, tag & 0xff,
66 (tag >> 8) & 0xff,
67 (tag >> 16) & 0xff,
68 (tag >> 24) & 0xff,
69 size);
70}
71#endif
72
06219cb1
RS
73static int get_riff(AVIContext *avi, ByteIOContext *pb)
74{
75 uint32_t tag;
76 /* check RIFF header */
77 tag = get_le32(pb);
78
79 if (tag != MKTAG('R', 'I', 'F', 'F'))
80 return -1;
81 avi->riff_end = get_le32(pb); /* RIFF chunk size */
82 avi->riff_end += url_ftell(pb); /* RIFF chunk end */
83 tag = get_le32(pb);
84 if (tag != MKTAG('A', 'V', 'I', ' ') && tag != MKTAG('A', 'V', 'I', 'X'))
85 return -1;
86
87 return 0;
88}
89
1101abfe 90static int avi_read_header(AVFormatContext *s, AVFormatParameters *ap)
de6d9b64 91{
c9a65ca8 92 AVIContext *avi = s->priv_data;
de6d9b64 93 ByteIOContext *pb = &s->pb;
deb0a292 94 uint32_t tag, tag1, handler;
b559b29b 95 int codec_type, stream_index, frame_period, bit_rate, scale, rate;
247eadca
FB
96 unsigned int size, nb_frames;
97 int i, n;
de6d9b64 98 AVStream *st;
155e9ee9 99 AVIStream *ast;
9e8cd0db 100 int xan_video = 0; /* hack to support Xan A/V */
de6d9b64 101
06219cb1 102 if (get_riff(avi, pb) < 0)
de6d9b64 103 return -1;
1101abfe 104
de6d9b64
FB
105 /* first list tag */
106 stream_index = -1;
107 codec_type = -1;
108 frame_period = 0;
109 for(;;) {
110 if (url_feof(pb))
111 goto fail;
112 tag = get_le32(pb);
113 size = get_le32(pb);
114#ifdef DEBUG
115 print_tag("tag", tag, size);
116#endif
117
118 switch(tag) {
119 case MKTAG('L', 'I', 'S', 'T'):
120 /* ignored, except when start of video packets */
121 tag1 = get_le32(pb);
122#ifdef DEBUG
123 print_tag("list", tag1, 0);
124#endif
125 if (tag1 == MKTAG('m', 'o', 'v', 'i')) {
155e9ee9 126 avi->movi_list = url_ftell(pb) - 4;
f8facaaf
MN
127 if(size) avi->movi_end = avi->movi_list + size;
128 else avi->movi_end = url_filesize(url_fileno(pb));
de6d9b64
FB
129#ifdef DEBUG
130 printf("movi end=%Lx\n", avi->movi_end);
131#endif
132 goto end_of_header;
133 }
134 break;
8f9298f8
RS
135 case MKTAG('d', 'm', 'l', 'h'):
136 avi->is_odml = 1;
137 url_fskip(pb, size + (size & 1));
138 break;
de6d9b64 139 case MKTAG('a', 'v', 'i', 'h'):
1101abfe
ZK
140 /* avi header */
141 /* using frame_period is bad idea */
de6d9b64
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142 frame_period = get_le32(pb);
143 bit_rate = get_le32(pb) * 8;
1101abfe 144 url_fskip(pb, 4 * 4);
247eadca
FB
145 n = get_le32(pb);
146 for(i=0;i<n;i++) {
155e9ee9 147 AVIStream *ast;
7458ccbb 148 st = av_new_stream(s, i);
de6d9b64
FB
149 if (!st)
150 goto fail;
9ee91c2f 151
155e9ee9
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152 ast = av_mallocz(sizeof(AVIStream));
153 if (!ast)
154 goto fail;
155 st->priv_data = ast;
1101abfe 156 }
de6d9b64
FB
157 url_fskip(pb, size - 7 * 4);
158 break;
159 case MKTAG('s', 't', 'r', 'h'):
160 /* stream header */
161 stream_index++;
162 tag1 = get_le32(pb);
7458ccbb 163 handler = get_le32(pb); /* codec tag */
cc11e2b3
MN
164#ifdef DEBUG
165 print_tag("strh", tag1, -1);
166#endif
de6d9b64 167 switch(tag1) {
deb0a292
RS
168 case MKTAG('i', 'a', 'v', 's'):
169 case MKTAG('i', 'v', 'a', 's'):
7458ccbb
RS
170 /*
171 * After some consideration -- I don't think we
172 * have to support anything but DV in a type1 AVIs.
173 */
deb0a292
RS
174 if (s->nb_streams != 1)
175 goto fail;
7458ccbb
RS
176
177 if (handler != MKTAG('d', 'v', 's', 'd') &&
178 handler != MKTAG('d', 'v', 'h', 'd') &&
179 handler != MKTAG('d', 'v', 's', 'l'))
180 goto fail;
ddaae6a9
RS
181
182 av_freep(&s->streams[0]->codec.extradata);
183 av_freep(&s->streams[0]);
184 s->nb_streams = 0;
185 avi->dv_demux = dv_init_demux(s);
7458ccbb
RS
186 if (!avi->dv_demux)
187 goto fail;
ddaae6a9
RS
188 stream_index = s->nb_streams - 1;
189 url_fskip(pb, size - 8);
190 break;
deb0a292 191 case MKTAG('v', 'i', 'd', 's'):
de6d9b64 192 codec_type = CODEC_TYPE_VIDEO;
b559b29b
MN
193
194 if (stream_index >= s->nb_streams) {
7458ccbb 195 url_fskip(pb, size - 8);
b559b29b
MN
196 break;
197 }
198
199 st = s->streams[stream_index];
155e9ee9 200 ast = st->priv_data;
76e9d392 201 st->codec.stream_codec_tag= handler;
155e9ee9 202
de6d9b64
FB
203 get_le32(pb); /* flags */
204 get_le16(pb); /* priority */
205 get_le16(pb); /* language */
206 get_le32(pb); /* XXX: initial frame ? */
deb0a292
RS
207 scale = get_le32(pb); /* scale */
208 rate = get_le32(pb); /* rate */
b559b29b 209
14bea432 210 if(scale && rate){
14bea432 211 }else if(frame_period){
155e9ee9
FB
212 rate = 1000000;
213 scale = frame_period;
14bea432 214 }else{
155e9ee9
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215 rate = 25;
216 scale = 1;
14bea432 217 }
155e9ee9
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218 ast->rate = rate;
219 ast->scale = scale;
cdd5034f 220 av_set_pts_info(st, 64, scale, rate);
155e9ee9
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221 st->codec.frame_rate = rate;
222 st->codec.frame_rate_base = scale;
247eadca
FB
223 get_le32(pb); /* start */
224 nb_frames = get_le32(pb);
225 st->start_time = 0;
cde073b4
MN
226 st->duration = av_rescale(nb_frames,
227 st->codec.frame_rate_base * AV_TIME_BASE,
228 st->codec.frame_rate);
247eadca 229 url_fskip(pb, size - 9 * 4);
de6d9b64
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230 break;
231 case MKTAG('a', 'u', 'd', 's'):
247eadca 232 {
155e9ee9 233 unsigned int length;
247eadca
FB
234
235 codec_type = CODEC_TYPE_AUDIO;
236
237 if (stream_index >= s->nb_streams) {
7458ccbb 238 url_fskip(pb, size - 8);
247eadca
FB
239 break;
240 }
241 st = s->streams[stream_index];
155e9ee9
FB
242 ast = st->priv_data;
243
247eadca
FB
244 get_le32(pb); /* flags */
245 get_le16(pb); /* priority */
246 get_le16(pb); /* language */
247 get_le32(pb); /* initial frame */
155e9ee9
FB
248 ast->scale = get_le32(pb); /* scale */
249 ast->rate = get_le32(pb);
cdd5034f 250 av_set_pts_info(st, 64, ast->scale, ast->rate);
1fa3d65d 251 ast->start= get_le32(pb); /* start */
247eadca 252 length = get_le32(pb); /* length, in samples or bytes */
155e9ee9
FB
253 get_le32(pb); /* buffer size */
254 get_le32(pb); /* quality */
255 ast->sample_size = get_le32(pb); /* sample ssize */
1fa3d65d 256//av_log(NULL, AV_LOG_DEBUG, "%d %d %d %d\n", ast->scale, ast->rate, ast->sample_size, ast->start);
247eadca 257 st->start_time = 0;
cde073b4
MN
258 if (ast->rate != 0)
259 st->duration = (int64_t)length * AV_TIME_BASE / ast->rate;
155e9ee9 260 url_fskip(pb, size - 12 * 4);
247eadca 261 }
9bf9a5fc 262 break;
cc11e2b3
MN
263 case MKTAG('t', 'x', 't', 's'):
264 //FIXME
265 codec_type = CODEC_TYPE_DATA; //CODEC_TYPE_SUB ? FIXME
266 url_fskip(pb, size - 8);
267 break;
9bf9a5fc
MN
268 default:
269 goto fail;
de6d9b64
FB
270 }
271 break;
272 case MKTAG('s', 't', 'r', 'f'):
273 /* stream header */
7458ccbb 274 if (stream_index >= s->nb_streams || avi->dv_demux) {
de6d9b64
FB
275 url_fskip(pb, size);
276 } else {
277 st = s->streams[stream_index];
278 switch(codec_type) {
279 case CODEC_TYPE_VIDEO:
280 get_le32(pb); /* size */
281 st->codec.width = get_le32(pb);
282 st->codec.height = get_le32(pb);
de6d9b64 283 get_le16(pb); /* panes */
b559b29b 284 st->codec.bits_per_sample= get_le16(pb); /* depth */
de6d9b64 285 tag1 = get_le32(pb);
b559b29b
MN
286 get_le32(pb); /* ImageSize */
287 get_le32(pb); /* XPelsPerMeter */
288 get_le32(pb); /* YPelsPerMeter */
289 get_le32(pb); /* ClrUsed */
290 get_le32(pb); /* ClrImportant */
291
292 st->codec.extradata_size= size - 10*4;
5ae2c73e 293 st->codec.extradata= av_malloc(st->codec.extradata_size);
b559b29b 294 get_buffer(pb, st->codec.extradata, st->codec.extradata_size);
952c69c4
MN
295
296 if(st->codec.extradata_size & 1) //FIXME check if the encoder really did this correctly
297 get_byte(pb);
b559b29b 298
5e29abf8
RT
299 /* Extract palette from extradata if bpp <= 8 */
300 /* This code assumes that extradata contains only palette */
301 /* This is true for all paletted codecs implemented in ffmpeg */
302 if (st->codec.extradata_size && (st->codec.bits_per_sample <= 8)) {
303 st->codec.palctrl = av_mallocz(sizeof(AVPaletteControl));
304#ifdef WORDS_BIGENDIAN
19d053c5
RS
305 for (i = 0; i < FFMIN(st->codec.extradata_size, AVPALETTE_SIZE)/4; i++)
306 st->codec.palctrl->palette[i] = bswap_32(((uint32_t*)st->codec.extradata)[i]);
5e29abf8
RT
307#else
308 memcpy(st->codec.palctrl->palette, st->codec.extradata,
309 FFMIN(st->codec.extradata_size, AVPALETTE_SIZE));
310#endif
311 st->codec.palctrl->palette_changed = 1;
312 }
313
de6d9b64
FB
314#ifdef DEBUG
315 print_tag("video", tag1, 0);
316#endif
317 st->codec.codec_type = CODEC_TYPE_VIDEO;
318 st->codec.codec_tag = tag1;
319 st->codec.codec_id = codec_get_id(codec_bmp_tags, tag1);
9e8cd0db
MM
320 if (st->codec.codec_id == CODEC_ID_XAN_WC4)
321 xan_video = 1;
b559b29b 322// url_fskip(pb, size - 5 * 4);
de6d9b64 323 break;
9bf9a5fc 324 case CODEC_TYPE_AUDIO:
2e7973bb 325 get_wav_header(pb, &st->codec, size);
1cef9527
FR
326 if (size%2) /* 2-aligned (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */
327 url_fskip(pb, 1);
9e8cd0db
MM
328 /* special case time: To support Xan DPCM, hardcode
329 * the format if Xxan is the video codec */
155e9ee9
FB
330 st->need_parsing = 1;
331 /* force parsing as several audio frames can be in
332 one packet */
9e8cd0db
MM
333 if (xan_video)
334 st->codec.codec_id = CODEC_ID_XAN_DPCM;
de6d9b64
FB
335 break;
336 default:
75204092
MN
337 st->codec.codec_type = CODEC_TYPE_DATA;
338 st->codec.codec_id= CODEC_ID_NONE;
339 st->codec.codec_tag= 0;
de6d9b64
FB
340 url_fskip(pb, size);
341 break;
342 }
343 }
344 break;
345 default:
346 /* skip tag */
347 size += (size & 1);
348 url_fskip(pb, size);
349 break;
350 }
351 }
352 end_of_header:
353 /* check stream number */
354 if (stream_index != s->nb_streams - 1) {
355 fail:
356 for(i=0;i<s->nb_streams;i++) {
8a7b1b18 357 av_freep(&s->streams[i]->codec.extradata);
9145f8b3 358 av_freep(&s->streams[i]);
de6d9b64
FB
359 }
360 return -1;
361 }
1101abfe 362
42feef6b
MN
363 assert(!avi->index_loaded);
364 avi_load_index(s);
365 avi->index_loaded = 1;
366
de6d9b64
FB
367 return 0;
368}
369
1101abfe 370static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)
de6d9b64
FB
371{
372 AVIContext *avi = s->priv_data;
373 ByteIOContext *pb = &s->pb;
8f9298f8
RS
374 int n, d[8], size;
375 offset_t i;
7458ccbb 376 void* dstr;
deb0a292 377
df99755b 378 memset(d, -1, sizeof(int)*8);
7458ccbb
RS
379
380 if (avi->dv_demux) {
381 size = dv_get_packet(avi->dv_demux, pkt);
382 if (size >= 0)
383 return size;
2af7e610 384 }
7458ccbb 385
06219cb1 386 for(i=url_ftell(pb); !url_feof(pb); i++) {
df99755b 387 int j;
1101abfe 388
8f9298f8
RS
389 if (i >= avi->movi_end) {
390 if (avi->is_odml) {
391 url_fskip(pb, avi->riff_end - i);
392 avi->riff_end = avi->movi_end = url_filesize(url_fileno(pb));
393 } else
394 break;
06219cb1
RS
395 }
396
df99755b
MN
397 for(j=0; j<7; j++)
398 d[j]= d[j+1];
399 d[7]= get_byte(pb);
400
401 size= d[4] + (d[5]<<8) + (d[6]<<16) + (d[7]<<24);
402
df99755b 403 if( d[2] >= '0' && d[2] <= '9'
d2c5f0a4
MN
404 && d[3] >= '0' && d[3] <= '9'){
405 n= (d[2] - '0') * 10 + (d[3] - '0');
406 }else{
407 n= 100; //invalid stream id
df99755b 408 }
d2c5f0a4
MN
409//av_log(NULL, AV_LOG_DEBUG, "%X %X %X %X %X %X %X %X %lld %d %d\n", d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7], i, size, n);
410 if(i + size > avi->movi_end || d[0]<0)
411 continue;
412
413 //parse ix##
414 if( (d[0] == 'i' && d[1] == 'x' && n < s->nb_streams)
8f9298f8 415 //parse JUNK
d2c5f0a4 416 ||(d[0] == 'J' && d[1] == 'U' && d[2] == 'N' && d[3] == 'K')){
8f9298f8 417 url_fskip(pb, size);
d2c5f0a4
MN
418 i+= size;
419 memset(d, -1, sizeof(int)*8);
420//av_log(NULL, AV_LOG_DEBUG, "SKIP\n");
421 continue;
8f9298f8 422 }
d2c5f0a4 423
df99755b 424 if( d[0] >= '0' && d[0] <= '9'
d2c5f0a4
MN
425 && d[1] >= '0' && d[1] <= '9'){
426 n= (d[0] - '0') * 10 + (d[1] - '0');
427 }else{
428 n= 100; //invalid stream id
429 }
df99755b 430
d2c5f0a4
MN
431 //parse ##dc/##wb
432 if(n < s->nb_streams){
433 AVStream *st;
434 AVIStream *ast;
435 st = s->streams[n];
436 ast = st->priv_data;
437
438 if( (ast->prefix_count<5 && d[2]<128 && d[3]<128) ||
439 d[2]*256+d[3] == ast->prefix /*||
440 (d[2] == 'd' && d[3] == 'c') ||
441 (d[2] == 'w' && d[3] == 'b')*/) {
442
443//av_log(NULL, AV_LOG_DEBUG, "OK\n");
444 if(d[2]*256+d[3] == ast->prefix)
445 ast->prefix_count++;
446 else{
447 ast->prefix= d[2]*256+d[3];
448 ast->prefix_count= 0;
449 }
450
7458ccbb 451 av_new_packet(pkt, size);
2af7e610 452 get_buffer(pb, pkt->data, size);
7458ccbb 453 if (size & 1) {
2af7e610 454 get_byte(pb);
7458ccbb
RS
455 size++;
456 }
457
458 if (avi->dv_demux) {
459 dstr = pkt->destruct;
460 size = dv_produce_packet(avi->dv_demux, pkt,
461 pkt->data, pkt->size);
462 pkt->destruct = dstr;
155e9ee9 463 pkt->flags |= PKT_FLAG_KEY;
7458ccbb 464 } else {
155e9ee9 465 /* XXX: how to handle B frames in avi ? */
42feef6b
MN
466 pkt->dts = ast->frame_offset;
467// pkt->dts += ast->start;
1fa3d65d 468 if(ast->sample_size)
42feef6b 469 pkt->dts /= ast->sample_size;
f8facaaf 470//av_log(NULL, AV_LOG_DEBUG, "dts:%Ld offset:%d %d/%d smpl_siz:%d base:%d st:%d size:%d\n", pkt->dts, ast->frame_offset, ast->scale, ast->rate, ast->sample_size, AV_TIME_BASE, n, size);
7458ccbb 471 pkt->stream_index = n;
155e9ee9
FB
472 /* FIXME: We really should read index for that */
473 if (st->codec.codec_type == CODEC_TYPE_VIDEO) {
474 if (ast->frame_offset < ast->nb_index_entries) {
475 if (ast->index_entries[ast->frame_offset].flags & AVIIF_INDEX)
476 pkt->flags |= PKT_FLAG_KEY;
477 } else {
478 /* if no index, better to say that all frames
479 are key frames */
480 pkt->flags |= PKT_FLAG_KEY;
481 }
155e9ee9 482 } else {
155e9ee9
FB
483 pkt->flags |= PKT_FLAG_KEY;
484 }
1fa3d65d
MN
485 if(ast->sample_size)
486 ast->frame_offset += pkt->size;
487 else
488 ast->frame_offset++;
7458ccbb
RS
489 }
490 return size;
d2c5f0a4 491 }
df99755b 492 }
69bde0b2
MM
493 /* palette changed chunk */
494 if ( d[0] >= '0' && d[0] <= '9'
495 && d[1] >= '0' && d[1] <= '9'
496 && ((d[2] == 'p' && d[3] == 'c'))
497 && n < s->nb_streams && i + size <= avi->movi_end) {
498
499 AVStream *st;
500 int first, clr, flags, k, p;
501
502 st = s->streams[n];
503
504 first = get_byte(pb);
505 clr = get_byte(pb);
506 flags = get_le16(pb);
507 p = 4;
508 for (k = first; k < clr + first; k++) {
509 int r, g, b;
510 r = get_byte(pb);
511 g = get_byte(pb);
512 b = get_byte(pb);
513 get_byte(pb);
514 st->codec.palctrl->palette[k] = b + (g << 8) + (r << 16);
515 }
516 st->codec.palctrl->palette_changed = 1;
517 }
518
df99755b 519 }
d2c5f0a4 520
df99755b 521 return -1;
de6d9b64
FB
522}
523
155e9ee9
FB
524/* XXX: we make the implicit supposition that the position are sorted
525 for each stream */
526static int avi_read_idx1(AVFormatContext *s, int size)
527{
528 ByteIOContext *pb = &s->pb;
529 int nb_index_entries, i;
530 AVStream *st;
531 AVIStream *ast;
532 AVIIndexEntry *ie, *entries;
533 unsigned int index, tag, flags, pos, len;
534
535 nb_index_entries = size / 16;
536 if (nb_index_entries <= 0)
537 return -1;
538
539 /* read the entries and sort them in each stream component */
540 for(i = 0; i < nb_index_entries; i++) {
541 tag = get_le32(pb);
542 flags = get_le32(pb);
543 pos = get_le32(pb);
544 len = get_le32(pb);
545#if defined(DEBUG_SEEK) && 0
546 printf("%d: tag=0x%x flags=0x%x pos=0x%x len=%d\n",
547 i, tag, flags, pos, len);
548#endif
549 index = ((tag & 0xff) - '0') * 10;
550 index += ((tag >> 8) & 0xff) - '0';
551 if (index >= s->nb_streams)
552 continue;
553 st = s->streams[index];
554 ast = st->priv_data;
555
556 entries = av_fast_realloc(ast->index_entries,
557 &ast->index_entries_allocated_size,
558 (ast->nb_index_entries + 1) *
559 sizeof(AVIIndexEntry));
560 if (entries) {
561 ast->index_entries = entries;
562 ie = &entries[ast->nb_index_entries++];
563 ie->flags = flags;
564 ie->pos = pos;
565 ie->cum_len = ast->cum_len;
566 ast->cum_len += len;
567 }
568 }
569 return 0;
570}
571
572static int avi_load_index(AVFormatContext *s)
573{
574 AVIContext *avi = s->priv_data;
575 ByteIOContext *pb = &s->pb;
576 uint32_t tag, size;
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577 offset_t pos= url_ftell(pb);
578
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579 url_fseek(pb, avi->movi_end, SEEK_SET);
580#ifdef DEBUG_SEEK
581 printf("movi_end=0x%llx\n", avi->movi_end);
582#endif
583 for(;;) {
584 if (url_feof(pb))
585 break;
586 tag = get_le32(pb);
587 size = get_le32(pb);
588#ifdef DEBUG_SEEK
589 printf("tag=%c%c%c%c size=0x%x\n",
590 tag & 0xff,
591 (tag >> 8) & 0xff,
592 (tag >> 16) & 0xff,
593 (tag >> 24) & 0xff,
594 size);
595#endif
596 switch(tag) {
597 case MKTAG('i', 'd', 'x', '1'):
598 if (avi_read_idx1(s, size) < 0)
599 goto skip;
600 else
601 goto the_end;
602 break;
603 default:
604 skip:
605 size += (size & 1);
606 url_fskip(pb, size);
607 break;
608 }
609 }
610 the_end:
e6c0297f 611 url_fseek(pb, pos, SEEK_SET);
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612 return 0;
613}
614
615/* return the index entry whose position is immediately >= 'wanted_pos' */
616static int locate_frame_in_index(AVIIndexEntry *entries,
617 int nb_entries, int wanted_pos)
618{
619 int a, b, m, pos;
620
621 a = 0;
622 b = nb_entries - 1;
623 while (a <= b) {
624 m = (a + b) >> 1;
625 pos = entries[m].pos;
626 if (pos == wanted_pos)
627 goto found;
628 else if (pos > wanted_pos) {
629 b = m - 1;
630 } else {
631 a = m + 1;
632 }
633 }
634 m = a;
635 if (m > 0)
636 m--;
637 found:
638 return m;
639}
640
641static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp)
642{
643 AVIContext *avi = s->priv_data;
644 AVStream *st;
645 AVIStream *ast;
646 int frame_number, i;
647 int64_t pos;
648
649 if (!avi->index_loaded) {
650 /* we only load the index on demand */
651 avi_load_index(s);
652 avi->index_loaded = 1;
653 }
654 if (stream_index < 0) {
655 for(i = 0; i < s->nb_streams; i++) {
656 st = s->streams[i];
657 if (st->codec.codec_type == CODEC_TYPE_VIDEO)
658 goto found;
659 }
660 return -1;
661 found:
662 stream_index = i;
663 }
664
665 st = s->streams[stream_index];
666 if (st->codec.codec_type != CODEC_TYPE_VIDEO)
667 return -1;
668 ast = st->priv_data;
669 /* compute the frame number */
4fc2c644 670 frame_number = timestamp;
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671#ifdef DEBUG_SEEK
672 printf("timestamp=%0.3f nb_indexes=%d frame_number=%d\n",
673 (double)timestamp / AV_TIME_BASE,
674 ast->nb_index_entries, frame_number);
675#endif
676 /* find a closest key frame before */
677 if (frame_number >= ast->nb_index_entries)
678 return -1;
679 while (frame_number >= 0 &&
680 !(ast->index_entries[frame_number].flags & AVIIF_INDEX))
681 frame_number--;
682 if (frame_number < 0)
683 return -1;
684 ast->new_frame_offset = frame_number;
685
686 /* find the position */
687 pos = ast->index_entries[frame_number].pos;
688
689#ifdef DEBUG_SEEK
690 printf("key_frame_number=%d pos=0x%llx\n",
691 frame_number, pos);
692#endif
693
694 /* update the frame counters for all the other stream by looking
695 at the positions just after the one found */
696 for(i = 0; i < s->nb_streams; i++) {
697 int j;
698 if (i != stream_index) {
699 st = s->streams[i];
700 ast = st->priv_data;
701 if (ast->nb_index_entries <= 0)
702 return -1;
703 j = locate_frame_in_index(ast->index_entries,
704 ast->nb_index_entries,
705 pos);
706 /* get next frame */
707 if ((j + 1) < ast->nb_index_entries)
708 j++;
709 /* extract the current frame number */
1fa3d65d 710 if (ast->sample_size==0)
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711 ast->new_frame_offset = j;
712 else
713 ast->new_frame_offset = ast->index_entries[j].cum_len;
714 }
715 }
716
717 /* everything is OK now. We can update the frame offsets */
718 for(i = 0; i < s->nb_streams; i++) {
719 st = s->streams[i];
720 ast = st->priv_data;
721 ast->frame_offset = ast->new_frame_offset;
722#ifdef DEBUG_SEEK
723 printf("%d: frame_offset=%d\n", i,
724 ast->frame_offset);
725#endif
726 }
727 /* do the seek */
728 pos += avi->movi_list;
729 url_fseek(&s->pb, pos, SEEK_SET);
730 return 0;
731}
732
1101abfe 733static int avi_read_close(AVFormatContext *s)
de6d9b64 734{
5ae2c73e
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735 int i;
736 AVIContext *avi = s->priv_data;
5ae2c73e
MN
737
738 for(i=0;i<s->nb_streams;i++) {
739 AVStream *st = s->streams[i];
155e9ee9 740 AVIStream *ast = st->priv_data;
3144b152
MN
741 if(ast){
742 av_free(ast->index_entries);
743 av_free(ast);
744 }
5ae2c73e 745 av_free(st->codec.extradata);
5e29abf8 746 av_free(st->codec.palctrl);
5ae2c73e
MN
747 }
748
7458ccbb
RS
749 if (avi->dv_demux)
750 av_free(avi->dv_demux);
751
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752 return 0;
753}
754
755static int avi_probe(AVProbeData *p)
756{
757 /* check file header */
758 if (p->buf_size <= 32)
759 return 0;
760 if (p->buf[0] == 'R' && p->buf[1] == 'I' &&
761 p->buf[2] == 'F' && p->buf[3] == 'F' &&
762 p->buf[8] == 'A' && p->buf[9] == 'V' &&
763 p->buf[10] == 'I' && p->buf[11] == ' ')
764 return AVPROBE_SCORE_MAX;
765 else
766 return 0;
767}
768
769static AVInputFormat avi_iformat = {
770 "avi",
771 "avi format",
772 sizeof(AVIContext),
773 avi_probe,
774 avi_read_header,
775 avi_read_packet,
776 avi_read_close,
155e9ee9 777 avi_read_seek,
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FB
778};
779
780int avidec_init(void)
781{
782 av_register_input_format(&avi_iformat);
de6d9b64
FB
783 return 0;
784}