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ffmpeg / libavformat / avidec.c @ 30a43f2d

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1
/*
2
 * AVI decoder.
3
 * Copyright (c) 2001 Fabrice Bellard.
4
 *
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.
9
 *
10
 * This library is distributed in the hope that it will be useful,
11
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13
 * Lesser General Public License for more details.
14
 *
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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18
 */
19
#include "avformat.h"
20
#include "avi.h"
21
#include "dv.h"
22

    
23
#undef NDEBUG
24
#include <assert.h>
25

    
26
//#define DEBUG
27
//#define DEBUG_SEEK
28

    
29
typedef struct AVIStream {
30
    int64_t frame_offset; /* current frame (video) or byte (audio) counter
31
                         (used to compute the pts) */
32
    int remaining;
33
    int packet_size;
34

    
35
    int scale;
36
    int rate;
37
    int sample_size; /* audio only data */
38
    int start;
39

    
40
    int64_t cum_len; /* temporary storage (used during seek) */
41

    
42
    int prefix;                       ///< normally 'd'<<8 + 'c' or 'w'<<8 + 'b'
43
    int prefix_count;
44
} AVIStream;
45

    
46
typedef struct {
47
    int64_t  riff_end;
48
    int64_t  movi_end;
49
    offset_t movi_list;
50
    int index_loaded;
51
    int is_odml;
52
    int non_interleaved;
53
    int stream_index;
54
    DVDemuxContext* dv_demux;
55
} AVIContext;
56

    
57
static int avi_load_index(AVFormatContext *s);
58
static int guess_ni_flag(AVFormatContext *s);
59

    
60
#ifdef DEBUG
61
static void print_tag(const char *str, unsigned int tag, int size)
62
{
63
    printf("%s: tag=%c%c%c%c size=0x%x\n",
64
           str, tag & 0xff,
65
           (tag >> 8) & 0xff,
66
           (tag >> 16) & 0xff,
67
           (tag >> 24) & 0xff,
68
           size);
69
}
70
#endif
71

    
72
static int get_riff(AVIContext *avi, ByteIOContext *pb)
73
{
74
    uint32_t tag;
75
    /* check RIFF header */
76
    tag = get_le32(pb);
77

    
78
    if (tag != MKTAG('R', 'I', 'F', 'F'))
79
        return -1;
80
    avi->riff_end = get_le32(pb);   /* RIFF chunk size */
81
    avi->riff_end += url_ftell(pb); /* RIFF chunk end */
82
    tag = get_le32(pb);
83
    if (tag != MKTAG('A', 'V', 'I', ' ') && tag != MKTAG('A', 'V', 'I', 'X'))
84
        return -1;
85

    
86
    return 0;
87
}
88

    
89
static int read_braindead_odml_indx(AVFormatContext *s, int frame_num){
90
    ByteIOContext *pb = &s->pb;
91
    int longs_pre_entry= get_le16(pb);
92
    int index_sub_type = get_byte(pb);
93
    int index_type     = get_byte(pb);
94
    int entries_in_use = get_le32(pb);
95
    int chunk_id       = get_le32(pb);
96
    int64_t base       = get_le64(pb);
97
    int stream_id= 10*((chunk_id&0xFF) - '0') + (((chunk_id>>8)&0xFF) - '0');
98
    AVStream *st;
99
    AVIStream *ast;
100
    int i;
101

    
102
//    av_log(s, AV_LOG_ERROR, "longs_pre_entry:%d index_type:%d entries_in_use:%d chunk_id:%X base:%Ld\n",
103
//        longs_pre_entry,index_type, entries_in_use, chunk_id, base);
104

    
105
    if(stream_id > s->nb_streams || stream_id < 0)
106
        return -1;
107
    st= s->streams[stream_id];
108
    ast = st->priv_data;
109

    
110
    if(index_sub_type)
111
        return -1;
112

    
113
    get_le32(pb);
114

    
115
    if(index_type && longs_pre_entry != 2)
116
        return -1;
117
    if(index_type>1)
118
        return -1;
119

    
120
    for(i=0; i<entries_in_use; i++){
121
        if(index_type){
122
            int64_t pos= get_le32(pb) + base - 8;
123
            int len    = get_le32(pb);
124
            int key= len >= 0;
125
            len &= 0x7FFFFFFF;
126

    
127
//av_log(s, AV_LOG_ERROR, "pos:%Ld, len:%X\n", pos, len);
128
            av_add_index_entry(st, pos, ast->cum_len, len, 0, key ? AVINDEX_KEYFRAME : 0);
129

    
130
            if(ast->sample_size)
131
                ast->cum_len += len / ast->sample_size;
132
            else
133
                ast->cum_len ++;
134
        }else{
135
            int64_t offset= get_le64(pb);
136
            int size      = get_le32(pb);
137
            int duration  = get_le32(pb);
138
            int64_t pos= url_ftell(pb);
139

    
140
            url_fseek(pb, offset+8, SEEK_SET);
141
            read_braindead_odml_indx(s, frame_num);
142
            frame_num += duration;
143

    
144
            url_fseek(pb, pos, SEEK_SET);
145
        }
146
    }
147
    return 0;
148
}
149

    
150
static int avi_read_header(AVFormatContext *s, AVFormatParameters *ap)
151
{
152
    AVIContext *avi = s->priv_data;
153
    ByteIOContext *pb = &s->pb;
154
    uint32_t tag, tag1, handler;
155
    int codec_type, stream_index, frame_period, bit_rate;
156
    unsigned int size, nb_frames;
157
    int i, n;
158
    AVStream *st;
159
    AVIStream *ast;
160
    int xan_video = 0;  /* hack to support Xan A/V */
161

    
162
    avi->stream_index= -1;
163

    
164
    if (get_riff(avi, pb) < 0)
165
        return -1;
166

    
167
    /* first list tag */
168
    stream_index = -1;
169
    codec_type = -1;
170
    frame_period = 0;
171
    for(;;) {
172
        if (url_feof(pb))
173
            goto fail;
174
        tag = get_le32(pb);
175
        size = get_le32(pb);
176
#ifdef DEBUG
177
        print_tag("tag", tag, size);
178
#endif
179

    
180
        switch(tag) {
181
        case MKTAG('L', 'I', 'S', 'T'):
182
            /* ignored, except when start of video packets */
183
            tag1 = get_le32(pb);
184
#ifdef DEBUG
185
            print_tag("list", tag1, 0);
186
#endif
187
            if (tag1 == MKTAG('m', 'o', 'v', 'i')) {
188
                avi->movi_list = url_ftell(pb) - 4;
189
                if(size) avi->movi_end = avi->movi_list + size;
190
                else     avi->movi_end = url_fsize(pb);
191
#ifdef DEBUG
192
                printf("movi end=%Lx\n", avi->movi_end);
193
#endif
194
                goto end_of_header;
195
            }
196
            break;
197
        case MKTAG('d', 'm', 'l', 'h'):
198
            avi->is_odml = 1;
199
            url_fskip(pb, size + (size & 1));
200
            break;
201
        case MKTAG('a', 'v', 'i', 'h'):
202
            /* avi header */
203
            /* using frame_period is bad idea */
204
            frame_period = get_le32(pb);
205
            bit_rate = get_le32(pb) * 8;
206
            url_fskip(pb, 4 * 4);
207
            n = get_le32(pb);
208
            for(i=0;i<n;i++) {
209
                AVIStream *ast;
210
                st = av_new_stream(s, i);
211
                if (!st)
212
                    goto fail;
213

    
214
                ast = av_mallocz(sizeof(AVIStream));
215
                if (!ast)
216
                    goto fail;
217
                st->priv_data = ast;
218
            }
219
            url_fskip(pb, size - 7 * 4);
220
            break;
221
        case MKTAG('s', 't', 'r', 'h'):
222
            /* stream header */
223
            stream_index++;
224
            tag1 = get_le32(pb);
225
            handler = get_le32(pb); /* codec tag */
226
#ifdef DEBUG
227
        print_tag("strh", tag1, -1);
228
#endif
229
            if(tag1 == MKTAG('i', 'a', 'v', 's') || tag1 == MKTAG('i', 'v', 'a', 's')){
230
                /*
231
                 * After some consideration -- I don't think we
232
                 * have to support anything but DV in a type1 AVIs.
233
                 */
234
                if (s->nb_streams != 1)
235
                    goto fail;
236

    
237
                if (handler != MKTAG('d', 'v', 's', 'd') &&
238
                    handler != MKTAG('d', 'v', 'h', 'd') &&
239
                    handler != MKTAG('d', 'v', 's', 'l'))
240
                   goto fail;
241

    
242
                ast = s->streams[0]->priv_data;
243
                av_freep(&s->streams[0]->codec->extradata);
244
                av_freep(&s->streams[0]);
245
                s->nb_streams = 0;
246
                avi->dv_demux = dv_init_demux(s);
247
                if (!avi->dv_demux)
248
                    goto fail;
249
                s->streams[0]->priv_data = ast;
250
                url_fskip(pb, 3 * 4);
251
                ast->scale = get_le32(pb);
252
                ast->rate = get_le32(pb);
253
                stream_index = s->nb_streams - 1;
254
                url_fskip(pb, size - 7*4);
255
                break;
256
            }
257

    
258
            if (stream_index >= s->nb_streams) {
259
                url_fskip(pb, size - 8);
260
                break;
261
            }
262
            st = s->streams[stream_index];
263
            ast = st->priv_data;
264
            st->codec->stream_codec_tag= handler;
265

    
266
            get_le32(pb); /* flags */
267
            get_le16(pb); /* priority */
268
            get_le16(pb); /* language */
269
            get_le32(pb); /* initial frame */
270
            ast->scale = get_le32(pb);
271
            ast->rate = get_le32(pb);
272
            if(ast->scale && ast->rate){
273
            }else if(frame_period){
274
                ast->rate = 1000000;
275
                ast->scale = frame_period;
276
            }else{
277
                ast->rate = 25;
278
                ast->scale = 1;
279
            }
280
            av_set_pts_info(st, 64, ast->scale, ast->rate);
281

    
282
            ast->start= get_le32(pb); /* start */
283
            nb_frames = get_le32(pb);
284

    
285
            st->start_time = 0;
286
            st->duration = nb_frames;
287
            get_le32(pb); /* buffer size */
288
            get_le32(pb); /* quality */
289
            ast->sample_size = get_le32(pb); /* sample ssize */
290
//            av_log(NULL, AV_LOG_DEBUG, "%d %d %d %d\n", ast->rate, ast->scale, ast->start, ast->sample_size);
291

    
292
            switch(tag1) {
293
            case MKTAG('v', 'i', 'd', 's'):
294
                codec_type = CODEC_TYPE_VIDEO;
295

    
296
                ast->sample_size = 0;
297
                break;
298
            case MKTAG('a', 'u', 'd', 's'):
299
                codec_type = CODEC_TYPE_AUDIO;
300
                break;
301
            case MKTAG('t', 'x', 't', 's'):
302
                //FIXME
303
                codec_type = CODEC_TYPE_DATA; //CODEC_TYPE_SUB ?  FIXME
304
                break;
305
            case MKTAG('p', 'a', 'd', 's'):
306
                codec_type = CODEC_TYPE_UNKNOWN;
307
                stream_index--;
308
                break;
309
            default:
310
                av_log(s, AV_LOG_ERROR, "unknown stream type %X\n", tag1);
311
                goto fail;
312
            }
313
            url_fskip(pb, size - 12 * 4);
314
            break;
315
        case MKTAG('s', 't', 'r', 'f'):
316
            /* stream header */
317
            if (stream_index >= s->nb_streams || avi->dv_demux) {
318
                url_fskip(pb, size);
319
            } else {
320
                st = s->streams[stream_index];
321
                switch(codec_type) {
322
                case CODEC_TYPE_VIDEO:
323
                    get_le32(pb); /* size */
324
                    st->codec->width = get_le32(pb);
325
                    st->codec->height = get_le32(pb);
326
                    get_le16(pb); /* panes */
327
                    st->codec->bits_per_sample= get_le16(pb); /* depth */
328
                    tag1 = get_le32(pb);
329
                    get_le32(pb); /* ImageSize */
330
                    get_le32(pb); /* XPelsPerMeter */
331
                    get_le32(pb); /* YPelsPerMeter */
332
                    get_le32(pb); /* ClrUsed */
333
                    get_le32(pb); /* ClrImportant */
334

    
335
                 if(size > 10*4 && size<(1<<30)){
336
                    st->codec->extradata_size= size - 10*4;
337
                    st->codec->extradata= av_malloc(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
338
                    get_buffer(pb, st->codec->extradata, st->codec->extradata_size);
339
                 }
340

    
341
                    if(st->codec->extradata_size & 1) //FIXME check if the encoder really did this correctly
342
                        get_byte(pb);
343

    
344
                    /* Extract palette from extradata if bpp <= 8 */
345
                    /* This code assumes that extradata contains only palette */
346
                    /* This is true for all paletted codecs implemented in ffmpeg */
347
                    if (st->codec->extradata_size && (st->codec->bits_per_sample <= 8)) {
348
                        st->codec->palctrl = av_mallocz(sizeof(AVPaletteControl));
349
#ifdef WORDS_BIGENDIAN
350
                        for (i = 0; i < FFMIN(st->codec->extradata_size, AVPALETTE_SIZE)/4; i++)
351
                            st->codec->palctrl->palette[i] = bswap_32(((uint32_t*)st->codec->extradata)[i]);
352
#else
353
                        memcpy(st->codec->palctrl->palette, st->codec->extradata,
354
                               FFMIN(st->codec->extradata_size, AVPALETTE_SIZE));
355
#endif
356
                        st->codec->palctrl->palette_changed = 1;
357
                    }
358

    
359
#ifdef DEBUG
360
                    print_tag("video", tag1, 0);
361
#endif
362
                    st->codec->codec_type = CODEC_TYPE_VIDEO;
363
                    st->codec->codec_tag = tag1;
364
                    st->codec->codec_id = codec_get_id(codec_bmp_tags, tag1);
365
                    if (st->codec->codec_id == CODEC_ID_XAN_WC4)
366
                        xan_video = 1;
367
                    st->need_parsing = 2; //only parse headers dont do slower repacketization, this is needed to get the pict type which is needed for generating correct pts
368
//                    url_fskip(pb, size - 5 * 4);
369
                    break;
370
                case CODEC_TYPE_AUDIO:
371
                    get_wav_header(pb, st->codec, size);
372
                    if (size%2) /* 2-aligned (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */
373
                        url_fskip(pb, 1);
374
                    /* special case time: To support Xan DPCM, hardcode
375
                     * the format if Xxan is the video codec */
376
                    st->need_parsing = 1;
377
                    /* force parsing as several audio frames can be in
378
                       one packet */
379
                    if (xan_video)
380
                        st->codec->codec_id = CODEC_ID_XAN_DPCM;
381
                    break;
382
                default:
383
                    st->codec->codec_type = CODEC_TYPE_DATA;
384
                    st->codec->codec_id= CODEC_ID_NONE;
385
                    st->codec->codec_tag= 0;
386
                    url_fskip(pb, size);
387
                    break;
388
                }
389
            }
390
            break;
391
        case MKTAG('i', 'n', 'd', 'x'):
392
            i= url_ftell(pb);
393
            read_braindead_odml_indx(s, 0);
394
            avi->index_loaded=1;
395
            url_fseek(pb, i+size, SEEK_SET);
396
            break;
397
        default:
398
            /* skip tag */
399
            size += (size & 1);
400
            url_fskip(pb, size);
401
            break;
402
        }
403
    }
404
 end_of_header:
405
    /* check stream number */
406
    if (stream_index != s->nb_streams - 1) {
407
    fail:
408
        for(i=0;i<s->nb_streams;i++) {
409
            av_freep(&s->streams[i]->codec->extradata);
410
            av_freep(&s->streams[i]);
411
        }
412
        return -1;
413
    }
414

    
415
    if(!avi->index_loaded)
416
        avi_load_index(s);
417
    avi->index_loaded = 1;
418
    avi->non_interleaved |= guess_ni_flag(s);
419

    
420
    return 0;
421
}
422

    
423
static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)
424
{
425
    AVIContext *avi = s->priv_data;
426
    ByteIOContext *pb = &s->pb;
427
    int n, d[8], size;
428
    offset_t i, sync;
429
    void* dstr;
430

    
431
    if (avi->dv_demux) {
432
        size = dv_get_packet(avi->dv_demux, pkt);
433
        if (size >= 0)
434
            return size;
435
    }
436

    
437
    if(avi->non_interleaved){
438
        int best_stream_index = 0;
439
        AVStream *best_st= NULL;
440
        AVIStream *best_ast;
441
        int64_t best_ts= INT64_MAX;
442
        int i;
443

    
444
        for(i=0; i<s->nb_streams; i++){
445
            AVStream *st = s->streams[i];
446
            AVIStream *ast = st->priv_data;
447
            int64_t ts= ast->frame_offset;
448

    
449
            if(ast->sample_size)
450
                ts /= ast->sample_size;
451
            ts= av_rescale(ts, AV_TIME_BASE * (int64_t)st->time_base.num, st->time_base.den);
452

    
453
//            av_log(NULL, AV_LOG_DEBUG, "%Ld %d/%d %Ld\n", ts, st->time_base.num, st->time_base.den, ast->frame_offset);
454
            if(ts < best_ts){
455
                best_ts= ts;
456
                best_st= st;
457
                best_stream_index= i;
458
            }
459
        }
460
        best_ast = best_st->priv_data;
461
        best_ts= av_rescale(best_ts, best_st->time_base.den, AV_TIME_BASE * (int64_t)best_st->time_base.num); //FIXME a little ugly
462
        if(best_ast->remaining)
463
            i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD);
464
        else
465
            i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);
466

    
467
//        av_log(NULL, AV_LOG_DEBUG, "%d\n", i);
468
        if(i>=0){
469
            int64_t pos= best_st->index_entries[i].pos;
470
            pos += avi->movi_list + best_ast->packet_size - best_ast->remaining;
471
            url_fseek(&s->pb, pos, SEEK_SET);
472
//        av_log(NULL, AV_LOG_DEBUG, "pos=%Ld\n", pos);
473

    
474
            if(best_ast->remaining)
475
                avi->stream_index= best_stream_index;
476
            else
477
                avi->stream_index= -1;
478
        }
479
    }
480

    
481
resync:
482
    if(avi->stream_index >= 0){
483
        AVStream *st= s->streams[ avi->stream_index ];
484
        AVIStream *ast= st->priv_data;
485
        int size;
486

    
487
        if(ast->sample_size == 0)
488
            size= INT_MAX;
489
        else if(ast->sample_size < 32)
490
            size= 64*ast->sample_size;
491
        else
492
            size= ast->sample_size;
493

    
494
        if(size > ast->remaining)
495
            size= ast->remaining;
496
        av_get_packet(pb, pkt, size);
497

    
498
        if (avi->dv_demux) {
499
            dstr = pkt->destruct;
500
            size = dv_produce_packet(avi->dv_demux, pkt,
501
                                    pkt->data, pkt->size);
502
            pkt->destruct = dstr;
503
            pkt->flags |= PKT_FLAG_KEY;
504
        } else {
505
            /* XXX: how to handle B frames in avi ? */
506
            pkt->dts = ast->frame_offset;
507
//                pkt->dts += ast->start;
508
            if(ast->sample_size)
509
                pkt->dts /= ast->sample_size;
510
//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);
511
            pkt->stream_index = avi->stream_index;
512

    
513
            if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
514
                if(st->index_entries){
515
                    AVIndexEntry *e;
516
                    int index;
517

    
518
                    index= av_index_search_timestamp(st, pkt->dts, 0);
519
                    e= &st->index_entries[index];
520

    
521
                    if(index >= 0 && e->timestamp == ast->frame_offset){
522
                        if (e->flags & AVINDEX_KEYFRAME)
523
                            pkt->flags |= PKT_FLAG_KEY;
524
                    }
525
                } else {
526
                    /* if no index, better to say that all frames
527
                        are key frames */
528
                    pkt->flags |= PKT_FLAG_KEY;
529
                }
530
            } else {
531
                pkt->flags |= PKT_FLAG_KEY;
532
            }
533
            if(ast->sample_size)
534
                ast->frame_offset += pkt->size;
535
            else
536
                ast->frame_offset++;
537
        }
538
        ast->remaining -= size;
539
        if(!ast->remaining){
540
            avi->stream_index= -1;
541
            ast->packet_size= 0;
542
            if (size & 1) {
543
                get_byte(pb);
544
                size++;
545
            }
546
        }
547

    
548
        return size;
549
    }
550

    
551
    memset(d, -1, sizeof(int)*8);
552
    for(i=sync=url_ftell(pb); !url_feof(pb); i++) {
553
        int j;
554

    
555
        if (i >= avi->movi_end) {
556
            if (avi->is_odml) {
557
                url_fskip(pb, avi->riff_end - i);
558
                avi->riff_end = avi->movi_end = url_fsize(pb);
559
            } else
560
                break;
561
        }
562

    
563
        for(j=0; j<7; j++)
564
            d[j]= d[j+1];
565
        d[7]= get_byte(pb);
566

    
567
        size= d[4] + (d[5]<<8) + (d[6]<<16) + (d[7]<<24);
568

    
569
        if(    d[2] >= '0' && d[2] <= '9'
570
            && d[3] >= '0' && d[3] <= '9'){
571
            n= (d[2] - '0') * 10 + (d[3] - '0');
572
        }else{
573
            n= 100; //invalid stream id
574
        }
575
//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);
576
        if(i + size > avi->movi_end || d[0]<0)
577
            continue;
578

    
579
        //parse ix##
580
        if(  (d[0] == 'i' && d[1] == 'x' && n < s->nb_streams)
581
        //parse JUNK
582
           ||(d[0] == 'J' && d[1] == 'U' && d[2] == 'N' && d[3] == 'K')){
583
            url_fskip(pb, size);
584
//av_log(NULL, AV_LOG_DEBUG, "SKIP\n");
585
            goto resync;
586
        }
587

    
588
        if(    d[0] >= '0' && d[0] <= '9'
589
            && d[1] >= '0' && d[1] <= '9'){
590
            n= (d[0] - '0') * 10 + (d[1] - '0');
591
        }else{
592
            n= 100; //invalid stream id
593
        }
594

    
595
        //parse ##dc/##wb
596
        if(n < s->nb_streams){
597
          AVStream *st;
598
          AVIStream *ast;
599
          st = s->streams[n];
600
          ast = st->priv_data;
601

    
602
          if(   (st->discard >= AVDISCARD_DEFAULT && size==0)
603
             /*|| (st->discard >= AVDISCARD_NONKEY && !(pkt->flags & PKT_FLAG_KEY))*/ //FIXME needs a little reordering
604
             || st->discard >= AVDISCARD_ALL){
605
                if(ast->sample_size) ast->frame_offset += pkt->size;
606
                else                 ast->frame_offset++;
607
                url_fskip(pb, size);
608
                goto resync;
609
          }
610

    
611
          if(   ((ast->prefix_count<5 || sync+9 > i) && d[2]<128 && d[3]<128) ||
612
                d[2]*256+d[3] == ast->prefix /*||
613
                (d[2] == 'd' && d[3] == 'c') ||
614
                (d[2] == 'w' && d[3] == 'b')*/) {
615

    
616
//av_log(NULL, AV_LOG_DEBUG, "OK\n");
617
            if(d[2]*256+d[3] == ast->prefix)
618
                ast->prefix_count++;
619
            else{
620
                ast->prefix= d[2]*256+d[3];
621
                ast->prefix_count= 0;
622
            }
623

    
624
            avi->stream_index= n;
625
            ast->packet_size= size + 8;
626
            ast->remaining= size;
627
            goto resync;
628
          }
629
        }
630
        /* palette changed chunk */
631
        if (   d[0] >= '0' && d[0] <= '9'
632
            && d[1] >= '0' && d[1] <= '9'
633
            && ((d[2] == 'p' && d[3] == 'c'))
634
            && n < s->nb_streams && i + size <= avi->movi_end) {
635

    
636
            AVStream *st;
637
            int first, clr, flags, k, p;
638

    
639
            st = s->streams[n];
640

    
641
            first = get_byte(pb);
642
            clr = get_byte(pb);
643
            if(!clr) /* all 256 colors used */
644
                clr = 256;
645
            flags = get_le16(pb);
646
            p = 4;
647
            for (k = first; k < clr + first; k++) {
648
                int r, g, b;
649
                r = get_byte(pb);
650
                g = get_byte(pb);
651
                b = get_byte(pb);
652
                    get_byte(pb);
653
                st->codec->palctrl->palette[k] = b + (g << 8) + (r << 16);
654
            }
655
            st->codec->palctrl->palette_changed = 1;
656
            goto resync;
657
        }
658

    
659
    }
660

    
661
    return -1;
662
}
663

    
664
/* XXX: we make the implicit supposition that the position are sorted
665
   for each stream */
666
static int avi_read_idx1(AVFormatContext *s, int size)
667
{
668
    AVIContext *avi = s->priv_data;
669
    ByteIOContext *pb = &s->pb;
670
    int nb_index_entries, i;
671
    AVStream *st;
672
    AVIStream *ast;
673
    unsigned int index, tag, flags, pos, len;
674
    unsigned last_pos= -1;
675

    
676
    nb_index_entries = size / 16;
677
    if (nb_index_entries <= 0)
678
        return -1;
679

    
680
    /* read the entries and sort them in each stream component */
681
    for(i = 0; i < nb_index_entries; i++) {
682
        tag = get_le32(pb);
683
        flags = get_le32(pb);
684
        pos = get_le32(pb);
685
        len = get_le32(pb);
686
#if defined(DEBUG_SEEK)
687
        av_log(NULL, AV_LOG_DEBUG, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",
688
               i, tag, flags, pos, len);
689
#endif
690
        if(i==0 && pos > avi->movi_list)
691
            avi->movi_list= 0; //FIXME better check
692

    
693
        index = ((tag & 0xff) - '0') * 10;
694
        index += ((tag >> 8) & 0xff) - '0';
695
        if (index >= s->nb_streams)
696
            continue;
697
        st = s->streams[index];
698
        ast = st->priv_data;
699

    
700
#if defined(DEBUG_SEEK)
701
        av_log(NULL, AV_LOG_DEBUG, "%d cum_len=%d\n", len, ast->cum_len);
702
#endif
703
        if(last_pos == pos)
704
            avi->non_interleaved= 1;
705
        else
706
            av_add_index_entry(st, pos, ast->cum_len, len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);
707
        if(ast->sample_size)
708
            ast->cum_len += len / ast->sample_size;
709
        else
710
            ast->cum_len ++;
711
        last_pos= pos;
712
    }
713
    return 0;
714
}
715

    
716
static int guess_ni_flag(AVFormatContext *s){
717
    int i;
718
    int64_t last_start=0;
719
    int64_t first_end= INT64_MAX;
720

    
721
    for(i=0; i<s->nb_streams; i++){
722
        AVStream *st = s->streams[i];
723
        int n= st->nb_index_entries;
724

    
725
        if(n <= 0)
726
            continue;
727

    
728
        if(st->index_entries[0].pos > last_start)
729
            last_start= st->index_entries[0].pos;
730
        if(st->index_entries[n-1].pos < first_end)
731
            first_end= st->index_entries[n-1].pos;
732
    }
733
    return last_start > first_end;
734
}
735

    
736
static int avi_load_index(AVFormatContext *s)
737
{
738
    AVIContext *avi = s->priv_data;
739
    ByteIOContext *pb = &s->pb;
740
    uint32_t tag, size;
741
    offset_t pos= url_ftell(pb);
742

    
743
    url_fseek(pb, avi->movi_end, SEEK_SET);
744
#ifdef DEBUG_SEEK
745
    printf("movi_end=0x%llx\n", avi->movi_end);
746
#endif
747
    for(;;) {
748
        if (url_feof(pb))
749
            break;
750
        tag = get_le32(pb);
751
        size = get_le32(pb);
752
#ifdef DEBUG_SEEK
753
        printf("tag=%c%c%c%c size=0x%x\n",
754
               tag & 0xff,
755
               (tag >> 8) & 0xff,
756
               (tag >> 16) & 0xff,
757
               (tag >> 24) & 0xff,
758
               size);
759
#endif
760
        switch(tag) {
761
        case MKTAG('i', 'd', 'x', '1'):
762
            if (avi_read_idx1(s, size) < 0)
763
                goto skip;
764
            else
765
                goto the_end;
766
            break;
767
        default:
768
        skip:
769
            size += (size & 1);
770
            url_fskip(pb, size);
771
            break;
772
        }
773
    }
774
 the_end:
775
    url_fseek(pb, pos, SEEK_SET);
776
    return 0;
777
}
778

    
779
static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
780
{
781
    AVIContext *avi = s->priv_data;
782
    AVStream *st;
783
    int i, index;
784
    int64_t pos;
785

    
786
    if (!avi->index_loaded) {
787
        /* we only load the index on demand */
788
        avi_load_index(s);
789
        avi->index_loaded = 1;
790
    }
791
    assert(stream_index>= 0);
792

    
793
    st = s->streams[stream_index];
794
    index= av_index_search_timestamp(st, timestamp, flags);
795
    if(index<0)
796
        return -1;
797

    
798
    /* find the position */
799
    pos = st->index_entries[index].pos;
800
    timestamp = st->index_entries[index].timestamp;
801

    
802
//    av_log(NULL, AV_LOG_DEBUG, "XX %Ld %d %Ld\n", timestamp, index, st->index_entries[index].timestamp);
803

    
804
    for(i = 0; i < s->nb_streams; i++) {
805
        AVStream *st2 = s->streams[i];
806
        AVIStream *ast2 = st2->priv_data;
807

    
808
        ast2->packet_size=
809
        ast2->remaining= 0;
810

    
811
        if (st2->nb_index_entries <= 0)
812
            continue;
813

    
814
//        assert(st2->codec.block_align);
815
        assert(st2->time_base.den == ast2->rate);
816
        assert(st2->time_base.num == ast2->scale);
817
        index = av_index_search_timestamp(
818
                st2,
819
                av_rescale(timestamp, st2->time_base.den*(int64_t)st->time_base.num, st->time_base.den * (int64_t)st2->time_base.num),
820
                flags | AVSEEK_FLAG_BACKWARD);
821
        if(index<0)
822
            index=0;
823

    
824
        if(!avi->non_interleaved){
825
            while(index>0 && st2->index_entries[index].pos > pos)
826
                index--;
827
            while(index+1 < st2->nb_index_entries && st2->index_entries[index].pos < pos)
828
                index++;
829
        }
830

    
831
//        av_log(NULL, AV_LOG_DEBUG, "%Ld %d %Ld\n", timestamp, index, st2->index_entries[index].timestamp);
832
        /* extract the current frame number */
833
        ast2->frame_offset = st2->index_entries[index].timestamp;
834
        if(ast2->sample_size)
835
            ast2->frame_offset *=ast2->sample_size;
836
    }
837

    
838
    if (avi->dv_demux)
839
        dv_flush_audio_packets(avi->dv_demux);
840
    /* do the seek */
841
    pos += avi->movi_list;
842
    url_fseek(&s->pb, pos, SEEK_SET);
843
    avi->stream_index= -1;
844
    return 0;
845
}
846

    
847
static int avi_read_close(AVFormatContext *s)
848
{
849
    int i;
850
    AVIContext *avi = s->priv_data;
851

    
852
    for(i=0;i<s->nb_streams;i++) {
853
        AVStream *st = s->streams[i];
854
        AVIStream *ast = st->priv_data;
855
        av_free(ast);
856
        av_free(st->codec->extradata);
857
        av_free(st->codec->palctrl);
858
    }
859

    
860
    if (avi->dv_demux)
861
        av_free(avi->dv_demux);
862

    
863
    return 0;
864
}
865

    
866
static int avi_probe(AVProbeData *p)
867
{
868
    /* check file header */
869
    if (p->buf_size <= 32)
870
        return 0;
871
    if (p->buf[0] == 'R' && p->buf[1] == 'I' &&
872
        p->buf[2] == 'F' && p->buf[3] == 'F' &&
873
        p->buf[8] == 'A' && p->buf[9] == 'V' &&
874
        p->buf[10] == 'I' && p->buf[11] == ' ')
875
        return AVPROBE_SCORE_MAX;
876
    else
877
        return 0;
878
}
879

    
880
static AVInputFormat avi_iformat = {
881
    "avi",
882
    "avi format",
883
    sizeof(AVIContext),
884
    avi_probe,
885
    avi_read_header,
886
    avi_read_packet,
887
    avi_read_close,
888
    avi_read_seek,
889
};
890

    
891
int avidec_init(void)
892
{
893
    av_register_input_format(&avi_iformat);
894
    return 0;
895
}