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ffmpeg / libavformat / oggdec.c @ 49c2d290

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1
/*
2
 * Ogg bitstream support
3
 * Luca Barbato <lu_zero@gentoo.org>
4
 * Based on tcvp implementation
5
 *
6
 */
7

    
8
/**
9
    Copyright (C) 2005  Michael Ahlberg, Måns Rullgård
10

11
    Permission is hereby granted, free of charge, to any person
12
    obtaining a copy of this software and associated documentation
13
    files (the "Software"), to deal in the Software without
14
    restriction, including without limitation the rights to use, copy,
15
    modify, merge, publish, distribute, sublicense, and/or sell copies
16
    of the Software, and to permit persons to whom the Software is
17
    furnished to do so, subject to the following conditions:
18

19
    The above copyright notice and this permission notice shall be
20
    included in all copies or substantial portions of the Software.
21

22
    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
23
    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
24
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
25
    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
26
    HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
27
    WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
28
    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
29
    DEALINGS IN THE SOFTWARE.
30
**/
31

    
32

    
33
#include <stdio.h>
34
#include "oggdec.h"
35
#include "avformat.h"
36
#include "vorbiscomment.h"
37

    
38
#define MAX_PAGE_SIZE 65307
39
#define DECODER_BUFFER_SIZE MAX_PAGE_SIZE
40

    
41
static const struct ogg_codec * const ogg_codecs[] = {
42
    &ff_skeleton_codec,
43
    &ff_dirac_codec,
44
    &ff_speex_codec,
45
    &ff_vorbis_codec,
46
    &ff_theora_codec,
47
    &ff_flac_codec,
48
    &ff_old_dirac_codec,
49
    &ff_old_flac_codec,
50
    &ff_ogm_video_codec,
51
    &ff_ogm_audio_codec,
52
    &ff_ogm_text_codec,
53
    &ff_ogm_old_codec,
54
    NULL
55
};
56

    
57
//FIXME We could avoid some structure duplication
58
static int
59
ogg_save (AVFormatContext * s)
60
{
61
    struct ogg *ogg = s->priv_data;
62
    struct ogg_state *ost =
63
        av_malloc(sizeof (*ost) + (ogg->nstreams-1) * sizeof (*ogg->streams));
64
    int i;
65
    ost->pos = url_ftell (s->pb);
66
    ost->curidx = ogg->curidx;
67
    ost->next = ogg->state;
68
    ost->nstreams = ogg->nstreams;
69
    memcpy(ost->streams, ogg->streams, ogg->nstreams * sizeof(*ogg->streams));
70

    
71
    for (i = 0; i < ogg->nstreams; i++){
72
        struct ogg_stream *os = ogg->streams + i;
73
        os->buf = av_malloc (os->bufsize);
74
        memset (os->buf, 0, os->bufsize);
75
        memcpy (os->buf, ost->streams[i].buf, os->bufpos);
76
    }
77

    
78
    ogg->state = ost;
79

    
80
    return 0;
81
}
82

    
83
static int
84
ogg_restore (AVFormatContext * s, int discard)
85
{
86
    struct ogg *ogg = s->priv_data;
87
    ByteIOContext *bc = s->pb;
88
    struct ogg_state *ost = ogg->state;
89
    int i;
90

    
91
    if (!ost)
92
        return 0;
93

    
94
    ogg->state = ost->next;
95

    
96
    if (!discard){
97
        for (i = 0; i < ogg->nstreams; i++)
98
            av_free (ogg->streams[i].buf);
99

    
100
        url_fseek (bc, ost->pos, SEEK_SET);
101
        ogg->curidx = ost->curidx;
102
        ogg->nstreams = ost->nstreams;
103
        memcpy(ogg->streams, ost->streams,
104
               ost->nstreams * sizeof(*ogg->streams));
105
    }
106

    
107
    av_free (ost);
108

    
109
    return 0;
110
}
111

    
112
static int
113
ogg_reset (struct ogg * ogg)
114
{
115
    int i;
116

    
117
    for (i = 0; i < ogg->nstreams; i++){
118
        struct ogg_stream *os = ogg->streams + i;
119
        os->bufpos = 0;
120
        os->pstart = 0;
121
        os->psize = 0;
122
        os->granule = -1;
123
        os->lastpts = AV_NOPTS_VALUE;
124
        os->lastdts = AV_NOPTS_VALUE;
125
        os->sync_pos = -1;
126
        os->page_pos = 0;
127
        os->nsegs = 0;
128
        os->segp = 0;
129
        os->incomplete = 0;
130
    }
131

    
132
    ogg->curidx = -1;
133

    
134
    return 0;
135
}
136

    
137
static const struct ogg_codec *
138
ogg_find_codec (uint8_t * buf, int size)
139
{
140
    int i;
141

    
142
    for (i = 0; ogg_codecs[i]; i++)
143
        if (size >= ogg_codecs[i]->magicsize &&
144
            !memcmp (buf, ogg_codecs[i]->magic, ogg_codecs[i]->magicsize))
145
            return ogg_codecs[i];
146

    
147
    return NULL;
148
}
149

    
150
static int
151
ogg_new_stream (AVFormatContext * s, uint32_t serial)
152
{
153

    
154
    struct ogg *ogg = s->priv_data;
155
    int idx = ogg->nstreams++;
156
    AVStream *st;
157
    struct ogg_stream *os;
158

    
159
    ogg->streams = av_realloc (ogg->streams,
160
                               ogg->nstreams * sizeof (*ogg->streams));
161
    memset (ogg->streams + idx, 0, sizeof (*ogg->streams));
162
    os = ogg->streams + idx;
163
    os->serial = serial;
164
    os->bufsize = DECODER_BUFFER_SIZE;
165
    os->buf = av_malloc(os->bufsize);
166
    os->header = -1;
167

    
168
    st = av_new_stream (s, idx);
169
    if (!st)
170
        return AVERROR(ENOMEM);
171

    
172
    av_set_pts_info(st, 64, 1, 1000000);
173

    
174
    return idx;
175
}
176

    
177
static int
178
ogg_new_buf(struct ogg *ogg, int idx)
179
{
180
    struct ogg_stream *os = ogg->streams + idx;
181
    uint8_t *nb = av_malloc(os->bufsize);
182
    int size = os->bufpos - os->pstart;
183
    if(os->buf){
184
        memcpy(nb, os->buf + os->pstart, size);
185
        av_free(os->buf);
186
    }
187
    os->buf = nb;
188
    os->bufpos = size;
189
    os->pstart = 0;
190

    
191
    return 0;
192
}
193

    
194
static int
195
ogg_read_page (AVFormatContext * s, int *str)
196
{
197
    ByteIOContext *bc = s->pb;
198
    struct ogg *ogg = s->priv_data;
199
    struct ogg_stream *os;
200
    int i = 0;
201
    int flags, nsegs;
202
    uint64_t gp;
203
    uint32_t serial;
204
    uint32_t seq;
205
    uint32_t crc;
206
    int size, idx;
207
    uint8_t sync[4];
208
    int sp = 0;
209

    
210
    if (get_buffer (bc, sync, 4) < 4)
211
        return -1;
212

    
213
    do{
214
        int c;
215

    
216
        if (sync[sp & 3] == 'O' &&
217
            sync[(sp + 1) & 3] == 'g' &&
218
            sync[(sp + 2) & 3] == 'g' && sync[(sp + 3) & 3] == 'S')
219
            break;
220

    
221
        c = url_fgetc (bc);
222
        if (c < 0)
223
            return -1;
224
        sync[sp++ & 3] = c;
225
    }while (i++ < MAX_PAGE_SIZE);
226

    
227
    if (i >= MAX_PAGE_SIZE){
228
        av_log (s, AV_LOG_INFO, "ogg, can't find sync word\n");
229
        return -1;
230
    }
231

    
232
    if (url_fgetc (bc) != 0)      /* version */
233
        return -1;
234

    
235
    flags = url_fgetc (bc);
236
    gp = get_le64 (bc);
237
    serial = get_le32 (bc);
238
    seq = get_le32 (bc);
239
    crc = get_le32 (bc);
240
    nsegs = url_fgetc (bc);
241

    
242
    idx = ogg_find_stream (ogg, serial);
243
    if (idx < 0){
244
        idx = ogg_new_stream (s, serial);
245
        if (idx < 0)
246
            return -1;
247
    }
248

    
249
    os = ogg->streams + idx;
250
    os->page_pos = url_ftell(bc) - 27;
251

    
252
    if(os->psize > 0)
253
        ogg_new_buf(ogg, idx);
254

    
255
    if (get_buffer (bc, os->segments, nsegs) < nsegs)
256
        return -1;
257

    
258
    os->nsegs = nsegs;
259
    os->segp = 0;
260

    
261
    size = 0;
262
    for (i = 0; i < nsegs; i++)
263
        size += os->segments[i];
264

    
265
    if (flags & OGG_FLAG_CONT || os->incomplete){
266
        if (!os->psize){
267
            while (os->segp < os->nsegs){
268
                int seg = os->segments[os->segp++];
269
                os->pstart += seg;
270
                if (seg < 255)
271
                    break;
272
            }
273
            os->sync_pos = os->page_pos;
274
        }
275
    }else{
276
        os->psize = 0;
277
        os->sync_pos = os->page_pos;
278
    }
279

    
280
    if (os->bufsize - os->bufpos < size){
281
        uint8_t *nb = av_malloc (os->bufsize *= 2);
282
        memcpy (nb, os->buf, os->bufpos);
283
        av_free (os->buf);
284
        os->buf = nb;
285
    }
286

    
287
    if (get_buffer (bc, os->buf + os->bufpos, size) < size)
288
        return -1;
289

    
290
    os->bufpos += size;
291
    os->granule = gp;
292
    os->flags = flags;
293

    
294
    if (str)
295
        *str = idx;
296

    
297
    return 0;
298
}
299

    
300
static int
301
ogg_packet (AVFormatContext * s, int *str, int *dstart, int *dsize, int64_t *fpos)
302
{
303
    struct ogg *ogg = s->priv_data;
304
    int idx, i;
305
    struct ogg_stream *os;
306
    int complete = 0;
307
    int segp = 0, psize = 0;
308

    
309
#if 0
310
    av_log (s, AV_LOG_DEBUG, "ogg_packet: curidx=%i\n", ogg->curidx);
311
#endif
312

    
313
    do{
314
        idx = ogg->curidx;
315

    
316
        while (idx < 0){
317
            if (ogg_read_page (s, &idx) < 0)
318
                return -1;
319
        }
320

    
321
        os = ogg->streams + idx;
322

    
323
#if 0
324
        av_log (s, AV_LOG_DEBUG,
325
                "ogg_packet: idx=%d pstart=%d psize=%d segp=%d nsegs=%d\n",
326
                idx, os->pstart, os->psize, os->segp, os->nsegs);
327
#endif
328

    
329
        if (!os->codec){
330
            if (os->header < 0){
331
                os->codec = ogg_find_codec (os->buf, os->bufpos);
332
                if (!os->codec){
333
                    os->header = 0;
334
                    return 0;
335
                }
336
            }else{
337
                return 0;
338
            }
339
        }
340

    
341
        segp = os->segp;
342
        psize = os->psize;
343

    
344
        while (os->segp < os->nsegs){
345
            int ss = os->segments[os->segp++];
346
            os->psize += ss;
347
            if (ss < 255){
348
                complete = 1;
349
                break;
350
            }
351
        }
352

    
353
        if (!complete && os->segp == os->nsegs){
354
            ogg->curidx = -1;
355
            os->incomplete = 1;
356
        }
357
    }while (!complete);
358

    
359
#if 0
360
    av_log (s, AV_LOG_DEBUG,
361
            "ogg_packet: idx %i, frame size %i, start %i\n",
362
            idx, os->psize, os->pstart);
363
#endif
364

    
365
    ogg->curidx = idx;
366
    os->incomplete = 0;
367

    
368
    if (os->header) {
369
        os->header = os->codec->header (s, idx);
370
        if (!os->header){
371
            os->segp = segp;
372
            os->psize = psize;
373
            if (!ogg->headers)
374
                s->data_offset = os->sync_pos;
375
            ogg->headers = 1;
376
        }else{
377
            os->pstart += os->psize;
378
            os->psize = 0;
379
        }
380
    } else {
381
        os->pflags = 0;
382
        os->pduration = 0;
383
        if (os->codec && os->codec->packet)
384
            os->codec->packet (s, idx);
385
        if (str)
386
            *str = idx;
387
        if (dstart)
388
            *dstart = os->pstart;
389
        if (dsize)
390
            *dsize = os->psize;
391
        if (fpos)
392
            *fpos = os->sync_pos;
393
        os->pstart += os->psize;
394
        os->psize = 0;
395
        os->sync_pos = os->page_pos;
396
    }
397

    
398
    // determine whether there are more complete packets in this page
399
    // if not, the page's granule will apply to this packet
400
    os->page_end = 1;
401
    for (i = os->segp; i < os->nsegs; i++)
402
        if (os->segments[i] < 255) {
403
            os->page_end = 0;
404
            break;
405
        }
406

    
407
    if (os->segp == os->nsegs)
408
        ogg->curidx = -1;
409

    
410
    return 0;
411
}
412

    
413
static int
414
ogg_get_headers (AVFormatContext * s)
415
{
416
    struct ogg *ogg = s->priv_data;
417

    
418
    do{
419
        if (ogg_packet (s, NULL, NULL, NULL, NULL) < 0)
420
            return -1;
421
    }while (!ogg->headers);
422

    
423
#if 0
424
    av_log (s, AV_LOG_DEBUG, "found headers\n");
425
#endif
426

    
427
    return 0;
428
}
429

    
430
static int
431
ogg_get_length (AVFormatContext * s)
432
{
433
    struct ogg *ogg = s->priv_data;
434
    int idx = -1, i;
435
    int64_t size, end;
436

    
437
    if(url_is_streamed(s->pb))
438
        return 0;
439

    
440
// already set
441
    if (s->duration != AV_NOPTS_VALUE)
442
        return 0;
443

    
444
    size = url_fsize(s->pb);
445
    if(size < 0)
446
        return 0;
447
    end = size > MAX_PAGE_SIZE? size - MAX_PAGE_SIZE: 0;
448

    
449
    ogg_save (s);
450
    url_fseek (s->pb, end, SEEK_SET);
451

    
452
    while (!ogg_read_page (s, &i)){
453
        if (ogg->streams[i].granule != -1 && ogg->streams[i].granule != 0 &&
454
            ogg->streams[i].codec)
455
            idx = i;
456
    }
457

    
458
    if (idx != -1){
459
        s->streams[idx]->duration =
460
            ogg_gptopts (s, idx, ogg->streams[idx].granule, NULL);
461
        if (s->streams[idx]->start_time != AV_NOPTS_VALUE)
462
            s->streams[idx]->duration -= s->streams[idx]->start_time;
463
    }
464

    
465
    ogg_restore (s, 0);
466

    
467
    return 0;
468
}
469

    
470

    
471
static int
472
ogg_read_header (AVFormatContext * s, AVFormatParameters * ap)
473
{
474
    struct ogg *ogg = s->priv_data;
475
    int i;
476
    ogg->curidx = -1;
477
    //linear headers seek from start
478
    if (ogg_get_headers (s) < 0){
479
        return -1;
480
    }
481

    
482
    for (i = 0; i < ogg->nstreams; i++)
483
        if (ogg->streams[i].header < 0)
484
            ogg->streams[i].codec = NULL;
485

    
486
    //linear granulepos seek from end
487
    ogg_get_length (s);
488

    
489
    //fill the extradata in the per codec callbacks
490
    return 0;
491
}
492

    
493
static int64_t ogg_calc_pts(AVFormatContext *s, int idx, int64_t *dts)
494
{
495
    struct ogg *ogg = s->priv_data;
496
    struct ogg_stream *os = ogg->streams + idx;
497
    int64_t pts = AV_NOPTS_VALUE;
498

    
499
    if (dts)
500
        *dts = AV_NOPTS_VALUE;
501

    
502
    if (os->lastpts != AV_NOPTS_VALUE) {
503
        pts = os->lastpts;
504
        os->lastpts = AV_NOPTS_VALUE;
505
    }
506
    if (os->lastdts != AV_NOPTS_VALUE) {
507
        if (dts)
508
            *dts = os->lastdts;
509
        os->lastdts = AV_NOPTS_VALUE;
510
    }
511
    if (os->page_end) {
512
        if (os->granule != -1LL) {
513
            if (os->codec && os->codec->granule_is_start)
514
                pts = ogg_gptopts(s, idx, os->granule, dts);
515
            else
516
                os->lastpts = ogg_gptopts(s, idx, os->granule, &os->lastdts);
517
            os->granule = -1LL;
518
        } else
519
            av_log(s, AV_LOG_WARNING, "Packet is missing granule\n");
520
    }
521
    return pts;
522
}
523

    
524
static int
525
ogg_read_packet (AVFormatContext * s, AVPacket * pkt)
526
{
527
    struct ogg *ogg;
528
    struct ogg_stream *os;
529
    int idx = -1;
530
    int pstart, psize;
531
    int64_t fpos, pts, dts;
532

    
533
    //Get an ogg packet
534
retry:
535
    do{
536
        if (ogg_packet (s, &idx, &pstart, &psize, &fpos) < 0)
537
            return AVERROR(EIO);
538
    }while (idx < 0 || !s->streams[idx]);
539

    
540
    ogg = s->priv_data;
541
    os = ogg->streams + idx;
542

    
543
    // pflags might not be set until after this
544
    pts = ogg_calc_pts(s, idx, &dts);
545

    
546
    if (os->keyframe_seek && !(os->pflags & AV_PKT_FLAG_KEY))
547
        goto retry;
548
    os->keyframe_seek = 0;
549

    
550
    //Alloc a pkt
551
    if (av_new_packet (pkt, psize) < 0)
552
        return AVERROR(EIO);
553
    pkt->stream_index = idx;
554
    memcpy (pkt->data, os->buf + pstart, psize);
555

    
556
    pkt->pts = pts;
557
    pkt->dts = dts;
558
    pkt->flags = os->pflags;
559
    pkt->duration = os->pduration;
560
    pkt->pos = fpos;
561

    
562
    return psize;
563
}
564

    
565

    
566
static int
567
ogg_read_close (AVFormatContext * s)
568
{
569
    struct ogg *ogg = s->priv_data;
570
    int i;
571

    
572
    for (i = 0; i < ogg->nstreams; i++){
573
        av_free (ogg->streams[i].buf);
574
        av_free (ogg->streams[i].private);
575
    }
576
    av_free (ogg->streams);
577
    return 0;
578
}
579

    
580

    
581
static int64_t
582
ogg_read_timestamp (AVFormatContext * s, int stream_index, int64_t * pos_arg,
583
                    int64_t pos_limit)
584
{
585
    struct ogg *ogg = s->priv_data;
586
    struct ogg_stream *os = ogg->streams + stream_index;
587
    ByteIOContext *bc = s->pb;
588
    int64_t pts = AV_NOPTS_VALUE;
589
    int i;
590
    url_fseek(bc, *pos_arg, SEEK_SET);
591
    ogg_reset(ogg);
592

    
593
    while (url_ftell(bc) < pos_limit && !ogg_packet(s, &i, NULL, NULL, pos_arg)) {
594
        if (i == stream_index) {
595
            pts = ogg_calc_pts(s, i, NULL);
596
            if (os->keyframe_seek && !(os->pflags & AV_PKT_FLAG_KEY))
597
                pts = AV_NOPTS_VALUE;
598
        }
599
        if (pts != AV_NOPTS_VALUE)
600
            break;
601
    }
602
    ogg_reset(ogg);
603
    return pts;
604
}
605

    
606
static int ogg_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
607
{
608
    struct ogg *ogg = s->priv_data;
609
    struct ogg_stream *os = ogg->streams + stream_index;
610
    int ret;
611

    
612
    // Try seeking to a keyframe first. If this fails (very possible),
613
    // av_seek_frame will fall back to ignoring keyframes
614
    if (s->streams[stream_index]->codec->codec_type == AVMEDIA_TYPE_VIDEO
615
        && !(flags & AVSEEK_FLAG_ANY))
616
        os->keyframe_seek = 1;
617

    
618
    ret = av_seek_frame_binary(s, stream_index, timestamp, flags);
619
    if (ret < 0)
620
        os->keyframe_seek = 0;
621
    return ret;
622
}
623

    
624
static int ogg_probe(AVProbeData *p)
625
{
626
    if (p->buf[0] == 'O' && p->buf[1] == 'g' &&
627
        p->buf[2] == 'g' && p->buf[3] == 'S' &&
628
        p->buf[4] == 0x0 && p->buf[5] <= 0x7 )
629
        return AVPROBE_SCORE_MAX;
630
    else
631
        return 0;
632
}
633

    
634
AVInputFormat ogg_demuxer = {
635
    "ogg",
636
    NULL_IF_CONFIG_SMALL("Ogg"),
637
    sizeof (struct ogg),
638
    ogg_probe,
639
    ogg_read_header,
640
    ogg_read_packet,
641
    ogg_read_close,
642
    ogg_read_seek,
643
    ogg_read_timestamp,
644
    .extensions = "ogg",
645
    .metadata_conv = ff_vorbiscomment_metadata_conv,
646
};