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ffmpeg / libavformat / oggdec.c @ 03700d39

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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,
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    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
    if (os->granule == -1)
366
        av_log(s, AV_LOG_WARNING, "Page at %"PRId64" is missing granule\n", os->page_pos);
367

    
368
    ogg->curidx = idx;
369
    os->incomplete = 0;
370

    
371
    if (os->header) {
372
        os->header = os->codec->header (s, idx);
373
        if (!os->header){
374
            os->segp = segp;
375
            os->psize = psize;
376
            if (!ogg->headers)
377
                s->data_offset = os->sync_pos;
378
            ogg->headers = 1;
379
        }else{
380
            os->pstart += os->psize;
381
            os->psize = 0;
382
        }
383
    } else {
384
        os->pflags = 0;
385
        os->pduration = 0;
386
        if (os->codec && os->codec->packet)
387
            os->codec->packet (s, idx);
388
        if (str)
389
            *str = idx;
390
        if (dstart)
391
            *dstart = os->pstart;
392
        if (dsize)
393
            *dsize = os->psize;
394
        if (fpos)
395
            *fpos = os->sync_pos;
396
        os->pstart += os->psize;
397
        os->psize = 0;
398
        os->sync_pos = os->page_pos;
399
    }
400

    
401
    // determine whether there are more complete packets in this page
402
    // if not, the page's granule will apply to this packet
403
    os->page_end = 1;
404
    for (i = os->segp; i < os->nsegs; i++)
405
        if (os->segments[i] < 255) {
406
            os->page_end = 0;
407
            break;
408
        }
409

    
410
    if (os->segp == os->nsegs)
411
        ogg->curidx = -1;
412

    
413
    return 0;
414
}
415

    
416
static int
417
ogg_get_headers (AVFormatContext * s)
418
{
419
    struct ogg *ogg = s->priv_data;
420

    
421
    do{
422
        if (ogg_packet (s, NULL, NULL, NULL, NULL) < 0)
423
            return -1;
424
    }while (!ogg->headers);
425

    
426
#if 0
427
    av_log (s, AV_LOG_DEBUG, "found headers\n");
428
#endif
429

    
430
    return 0;
431
}
432

    
433
static int
434
ogg_get_length (AVFormatContext * s)
435
{
436
    struct ogg *ogg = s->priv_data;
437
    int i;
438
    int64_t size, end;
439

    
440
    if(url_is_streamed(s->pb))
441
        return 0;
442

    
443
// already set
444
    if (s->duration != AV_NOPTS_VALUE)
445
        return 0;
446

    
447
    size = url_fsize(s->pb);
448
    if(size < 0)
449
        return 0;
450
    end = size > MAX_PAGE_SIZE? size - MAX_PAGE_SIZE: 0;
451

    
452
    ogg_save (s);
453
    url_fseek (s->pb, end, SEEK_SET);
454

    
455
    while (!ogg_read_page (s, &i)){
456
        if (ogg->streams[i].granule != -1 && ogg->streams[i].granule != 0 &&
457
            ogg->streams[i].codec) {
458
            s->streams[i]->duration =
459
                ogg_gptopts (s, i, ogg->streams[i].granule, NULL);
460
            if (s->streams[i]->start_time != AV_NOPTS_VALUE)
461
                s->streams[i]->duration -= s->streams[i]->start_time;
462
        }
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
        }
519
    }
520
    return pts;
521
}
522

    
523
static int
524
ogg_read_packet (AVFormatContext * s, AVPacket * pkt)
525
{
526
    struct ogg *ogg;
527
    struct ogg_stream *os;
528
    int idx = -1;
529
    int pstart, psize;
530
    int64_t fpos, pts, dts;
531

    
532
    //Get an ogg packet
533
retry:
534
    do{
535
        if (ogg_packet (s, &idx, &pstart, &psize, &fpos) < 0)
536
            return AVERROR(EIO);
537
    }while (idx < 0 || !s->streams[idx]);
538

    
539
    ogg = s->priv_data;
540
    os = ogg->streams + idx;
541

    
542
    // pflags might not be set until after this
543
    pts = ogg_calc_pts(s, idx, &dts);
544

    
545
    if (os->keyframe_seek && !(os->pflags & AV_PKT_FLAG_KEY))
546
        goto retry;
547
    os->keyframe_seek = 0;
548

    
549
    //Alloc a pkt
550
    if (av_new_packet (pkt, psize) < 0)
551
        return AVERROR(EIO);
552
    pkt->stream_index = idx;
553
    memcpy (pkt->data, os->buf + pstart, psize);
554

    
555
    pkt->pts = pts;
556
    pkt->dts = dts;
557
    pkt->flags = os->pflags;
558
    pkt->duration = os->pduration;
559
    pkt->pos = fpos;
560

    
561
    return psize;
562
}
563

    
564

    
565
static int
566
ogg_read_close (AVFormatContext * s)
567
{
568
    struct ogg *ogg = s->priv_data;
569
    int i;
570

    
571
    for (i = 0; i < ogg->nstreams; i++){
572
        av_free (ogg->streams[i].buf);
573
        av_free (ogg->streams[i].private);
574
    }
575
    av_free (ogg->streams);
576
    return 0;
577
}
578

    
579

    
580
static int64_t
581
ogg_read_timestamp (AVFormatContext * s, int stream_index, int64_t * pos_arg,
582
                    int64_t pos_limit)
583
{
584
    struct ogg *ogg = s->priv_data;
585
    struct ogg_stream *os = ogg->streams + stream_index;
586
    ByteIOContext *bc = s->pb;
587
    int64_t pts = AV_NOPTS_VALUE;
588
    int i;
589
    url_fseek(bc, *pos_arg, SEEK_SET);
590
    ogg_reset(ogg);
591

    
592
    while (url_ftell(bc) < pos_limit && !ogg_packet(s, &i, NULL, NULL, pos_arg)) {
593
        if (i == stream_index) {
594
            pts = ogg_calc_pts(s, i, NULL);
595
            if (os->keyframe_seek && !(os->pflags & AV_PKT_FLAG_KEY))
596
                pts = AV_NOPTS_VALUE;
597
        }
598
        if (pts != AV_NOPTS_VALUE)
599
            break;
600
    }
601
    ogg_reset(ogg);
602
    return pts;
603
}
604

    
605
static int ogg_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
606
{
607
    struct ogg *ogg = s->priv_data;
608
    struct ogg_stream *os = ogg->streams + stream_index;
609
    int ret;
610

    
611
    // Try seeking to a keyframe first. If this fails (very possible),
612
    // av_seek_frame will fall back to ignoring keyframes
613
    if (s->streams[stream_index]->codec->codec_type == AVMEDIA_TYPE_VIDEO
614
        && !(flags & AVSEEK_FLAG_ANY))
615
        os->keyframe_seek = 1;
616

    
617
    ret = av_seek_frame_binary(s, stream_index, timestamp, flags);
618
    if (ret < 0)
619
        os->keyframe_seek = 0;
620
    return ret;
621
}
622

    
623
static int ogg_probe(AVProbeData *p)
624
{
625
    if (p->buf[0] == 'O' && p->buf[1] == 'g' &&
626
        p->buf[2] == 'g' && p->buf[3] == 'S' &&
627
        p->buf[4] == 0x0 && p->buf[5] <= 0x7 )
628
        return AVPROBE_SCORE_MAX;
629
    else
630
        return 0;
631
}
632

    
633
AVInputFormat ogg_demuxer = {
634
    "ogg",
635
    NULL_IF_CONFIG_SMALL("Ogg"),
636
    sizeof (struct ogg),
637
    ogg_probe,
638
    ogg_read_header,
639
    ogg_read_packet,
640
    ogg_read_close,
641
    ogg_read_seek,
642
    ogg_read_timestamp,
643
    .extensions = "ogg",
644
    .flags = AVFMT_GENERIC_INDEX,
645
};