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ffmpeg / libavformat / flvdec.c @ 578d6861

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1
/*
2
 * FLV demuxer
3
 * Copyright (c) 2003 The Libav Project
4
 *
5
 * This demuxer will generate a 1 byte extradata for VP6F content.
6
 * It is composed of:
7
 *  - upper 4bits: difference between encoded width and visible width
8
 *  - lower 4bits: difference between encoded height and visible height
9
 *
10
 * This file is part of Libav.
11
 *
12
 * Libav is free software; you can redistribute it and/or
13
 * modify it under the terms of the GNU Lesser General Public
14
 * License as published by the Free Software Foundation; either
15
 * version 2.1 of the License, or (at your option) any later version.
16
 *
17
 * Libav is distributed in the hope that it will be useful,
18
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
20
 * Lesser General Public License for more details.
21
 *
22
 * You should have received a copy of the GNU Lesser General Public
23
 * License along with Libav; if not, write to the Free Software
24
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25
 */
26

    
27
#include "libavutil/avstring.h"
28
#include "libavcodec/bytestream.h"
29
#include "libavcodec/mpeg4audio.h"
30
#include "avformat.h"
31
#include "avio_internal.h"
32
#include "flv.h"
33

    
34
#define KEYFRAMES_TAG            "keyframes"
35
#define KEYFRAMES_TIMESTAMP_TAG  "times"
36
#define KEYFRAMES_BYTEOFFSET_TAG "filepositions"
37

    
38
typedef struct {
39
    int wrong_dts; ///< wrong dts due to negative cts
40
} FLVContext;
41

    
42
static int flv_probe(AVProbeData *p)
43
{
44
    const uint8_t *d;
45

    
46
    d = p->buf;
47
    if (d[0] == 'F' && d[1] == 'L' && d[2] == 'V' && d[3] < 5 && d[5]==0 && AV_RB32(d+5)>8) {
48
        return AVPROBE_SCORE_MAX;
49
    }
50
    return 0;
51
}
52

    
53
static void flv_set_audio_codec(AVFormatContext *s, AVStream *astream, int flv_codecid) {
54
    AVCodecContext *acodec = astream->codec;
55
    switch(flv_codecid) {
56
        //no distinction between S16 and S8 PCM codec flags
57
        case FLV_CODECID_PCM:
58
            acodec->codec_id = acodec->bits_per_coded_sample == 8 ? CODEC_ID_PCM_U8 :
59
#if HAVE_BIGENDIAN
60
                                CODEC_ID_PCM_S16BE;
61
#else
62
                                CODEC_ID_PCM_S16LE;
63
#endif
64
            break;
65
        case FLV_CODECID_PCM_LE:
66
            acodec->codec_id = acodec->bits_per_coded_sample == 8 ? CODEC_ID_PCM_U8 : CODEC_ID_PCM_S16LE; break;
67
        case FLV_CODECID_AAC  : acodec->codec_id = CODEC_ID_AAC;                                    break;
68
        case FLV_CODECID_ADPCM: acodec->codec_id = CODEC_ID_ADPCM_SWF;                              break;
69
        case FLV_CODECID_SPEEX:
70
            acodec->codec_id = CODEC_ID_SPEEX;
71
            acodec->sample_rate = 16000;
72
            break;
73
        case FLV_CODECID_MP3  : acodec->codec_id = CODEC_ID_MP3      ; astream->need_parsing = AVSTREAM_PARSE_FULL; break;
74
        case FLV_CODECID_NELLYMOSER_8KHZ_MONO:
75
            acodec->sample_rate = 8000; //in case metadata does not otherwise declare samplerate
76
            acodec->codec_id = CODEC_ID_NELLYMOSER;
77
            break;
78
        case FLV_CODECID_NELLYMOSER_16KHZ_MONO:
79
            acodec->sample_rate = 16000;
80
            acodec->codec_id = CODEC_ID_NELLYMOSER;
81
            break;
82
        case FLV_CODECID_NELLYMOSER:
83
            acodec->codec_id = CODEC_ID_NELLYMOSER;
84
            break;
85
        default:
86
            av_log(s, AV_LOG_INFO, "Unsupported audio codec (%x)\n", flv_codecid >> FLV_AUDIO_CODECID_OFFSET);
87
            acodec->codec_tag = flv_codecid >> FLV_AUDIO_CODECID_OFFSET;
88
    }
89
}
90

    
91
static int flv_set_video_codec(AVFormatContext *s, AVStream *vstream, int flv_codecid) {
92
    AVCodecContext *vcodec = vstream->codec;
93
    switch(flv_codecid) {
94
        case FLV_CODECID_H263  : vcodec->codec_id = CODEC_ID_FLV1   ; break;
95
        case FLV_CODECID_SCREEN: vcodec->codec_id = CODEC_ID_FLASHSV; break;
96
        case FLV_CODECID_SCREEN2: vcodec->codec_id = CODEC_ID_FLASHSV2; break;
97
        case FLV_CODECID_VP6   : vcodec->codec_id = CODEC_ID_VP6F   ;
98
        case FLV_CODECID_VP6A  :
99
            if(flv_codecid == FLV_CODECID_VP6A)
100
                vcodec->codec_id = CODEC_ID_VP6A;
101
            if(vcodec->extradata_size != 1) {
102
                vcodec->extradata_size = 1;
103
                vcodec->extradata = av_malloc(1);
104
            }
105
            vcodec->extradata[0] = avio_r8(s->pb);
106
            return 1; // 1 byte body size adjustment for flv_read_packet()
107
        case FLV_CODECID_H264:
108
            vcodec->codec_id = CODEC_ID_H264;
109
            return 3; // not 4, reading packet type will consume one byte
110
        default:
111
            av_log(s, AV_LOG_INFO, "Unsupported video codec (%x)\n", flv_codecid);
112
            vcodec->codec_tag = flv_codecid;
113
    }
114

    
115
    return 0;
116
}
117

    
118
static int amf_get_string(AVIOContext *ioc, char *buffer, int buffsize) {
119
    int length = avio_rb16(ioc);
120
    if(length >= buffsize) {
121
        avio_skip(ioc, length);
122
        return -1;
123
    }
124

    
125
    avio_read(ioc, buffer, length);
126

    
127
    buffer[length] = '\0';
128

    
129
    return length;
130
}
131

    
132
static int parse_keyframes_index(AVFormatContext *s, AVIOContext *ioc, AVStream *vstream, int64_t max_pos) {
133
    unsigned int arraylen = 0, timeslen = 0, fileposlen = 0, i;
134
    double num_val;
135
    char str_val[256];
136
    int64_t *times = NULL;
137
    int64_t *filepositions = NULL;
138
    int ret = AVERROR(ENOSYS);
139
    int64_t initial_pos = avio_tell(ioc);
140

    
141
    while (avio_tell(ioc) < max_pos - 2 && amf_get_string(ioc, str_val, sizeof(str_val)) > 0) {
142
        int64_t* current_array;
143

    
144
        // Expect array object in context
145
        if (avio_r8(ioc) != AMF_DATA_TYPE_ARRAY)
146
            break;
147

    
148
        arraylen = avio_rb32(ioc);
149
        /*
150
         * Expect only 'times' or 'filepositions' sub-arrays in other case refuse to use such metadata
151
         * for indexing
152
         */
153
        if (!strcmp(KEYFRAMES_TIMESTAMP_TAG, str_val) && !times) {
154
            if (!(times = av_mallocz(sizeof(*times) * arraylen))) {
155
                ret = AVERROR(ENOMEM);
156
                goto finish;
157
            }
158
            timeslen = arraylen;
159
            current_array = times;
160
        } else if (!strcmp(KEYFRAMES_BYTEOFFSET_TAG, str_val) && !filepositions) {
161
            if (!(filepositions = av_mallocz(sizeof(*filepositions) * arraylen))) {
162
                ret = AVERROR(ENOMEM);
163
                goto finish;
164
            }
165
            fileposlen = arraylen;
166
            current_array = filepositions;
167
        } else // unexpected metatag inside keyframes, will not use such metadata for indexing
168
            break;
169

    
170
        for (i = 0; i < arraylen && avio_tell(ioc) < max_pos - 1; i++) {
171
            if (avio_r8(ioc) != AMF_DATA_TYPE_NUMBER)
172
                goto finish;
173
            num_val = av_int2dbl(avio_rb64(ioc));
174
            current_array[i] = num_val;
175
        }
176
        if (times && filepositions) {
177
            // All done, exiting at a position allowing amf_parse_object
178
            // to finish parsing the object
179
            ret = 0;
180
            break;
181
        }
182
    }
183

    
184
    if (timeslen == fileposlen)
185
         for(i = 0; i < arraylen; i++)
186
             av_add_index_entry(vstream, filepositions[i], times[i]*1000, 0, 0, AVINDEX_KEYFRAME);
187
    else
188
        av_log(s, AV_LOG_WARNING, "Invalid keyframes object, skipping.\n");
189

    
190
finish:
191
    av_freep(&times);
192
    av_freep(&filepositions);
193
    // If we got unexpected data, but successfully reset back to
194
    // the start pos, the caller can continue parsing
195
    if (ret < 0 && avio_seek(ioc, initial_pos, SEEK_SET) > 0)
196
        return 0;
197
    return ret;
198
}
199

    
200
static int amf_parse_object(AVFormatContext *s, AVStream *astream, AVStream *vstream, const char *key, int64_t max_pos, int depth) {
201
    AVCodecContext *acodec, *vcodec;
202
    AVIOContext *ioc;
203
    AMFDataType amf_type;
204
    char str_val[256];
205
    double num_val;
206

    
207
    num_val = 0;
208
    ioc = s->pb;
209

    
210
    amf_type = avio_r8(ioc);
211

    
212
    switch(amf_type) {
213
        case AMF_DATA_TYPE_NUMBER:
214
            num_val = av_int2dbl(avio_rb64(ioc)); break;
215
        case AMF_DATA_TYPE_BOOL:
216
            num_val = avio_r8(ioc); break;
217
        case AMF_DATA_TYPE_STRING:
218
            if(amf_get_string(ioc, str_val, sizeof(str_val)) < 0)
219
                return -1;
220
            break;
221
        case AMF_DATA_TYPE_OBJECT: {
222
            unsigned int keylen;
223

    
224
            if (key && !strcmp(KEYFRAMES_TAG, key) && depth == 1)
225
                if (parse_keyframes_index(s, ioc, vstream, max_pos) < 0)
226
                    return -1;
227

    
228
            while(avio_tell(ioc) < max_pos - 2 && (keylen = avio_rb16(ioc))) {
229
                avio_skip(ioc, keylen); //skip key string
230
                if(amf_parse_object(s, NULL, NULL, NULL, max_pos, depth + 1) < 0)
231
                    return -1; //if we couldn't skip, bomb out.
232
            }
233
            if(avio_r8(ioc) != AMF_END_OF_OBJECT)
234
                return -1;
235
        }
236
            break;
237
        case AMF_DATA_TYPE_NULL:
238
        case AMF_DATA_TYPE_UNDEFINED:
239
        case AMF_DATA_TYPE_UNSUPPORTED:
240
            break; //these take up no additional space
241
        case AMF_DATA_TYPE_MIXEDARRAY:
242
            avio_skip(ioc, 4); //skip 32-bit max array index
243
            while(avio_tell(ioc) < max_pos - 2 && amf_get_string(ioc, str_val, sizeof(str_val)) > 0) {
244
                //this is the only case in which we would want a nested parse to not skip over the object
245
                if(amf_parse_object(s, astream, vstream, str_val, max_pos, depth + 1) < 0)
246
                    return -1;
247
            }
248
            if(avio_r8(ioc) != AMF_END_OF_OBJECT)
249
                return -1;
250
            break;
251
        case AMF_DATA_TYPE_ARRAY: {
252
            unsigned int arraylen, i;
253

    
254
            arraylen = avio_rb32(ioc);
255
            for(i = 0; i < arraylen && avio_tell(ioc) < max_pos - 1; i++) {
256
                if(amf_parse_object(s, NULL, NULL, NULL, max_pos, depth + 1) < 0)
257
                    return -1; //if we couldn't skip, bomb out.
258
            }
259
        }
260
            break;
261
        case AMF_DATA_TYPE_DATE:
262
            avio_skip(ioc, 8 + 2); //timestamp (double) and UTC offset (int16)
263
            break;
264
        default: //unsupported type, we couldn't skip
265
            return -1;
266
    }
267

    
268
    if(depth == 1 && key) { //only look for metadata values when we are not nested and key != NULL
269
        acodec = astream ? astream->codec : NULL;
270
        vcodec = vstream ? vstream->codec : NULL;
271

    
272
        if(amf_type == AMF_DATA_TYPE_BOOL) {
273
            av_strlcpy(str_val, num_val > 0 ? "true" : "false", sizeof(str_val));
274
            av_metadata_set2(&s->metadata, key, str_val, 0);
275
        } else if(amf_type == AMF_DATA_TYPE_NUMBER) {
276
            snprintf(str_val, sizeof(str_val), "%.f", num_val);
277
            av_metadata_set2(&s->metadata, key, str_val, 0);
278
            if(!strcmp(key, "duration")) s->duration = num_val * AV_TIME_BASE;
279
            else if(!strcmp(key, "videodatarate") && vcodec && 0 <= (int)(num_val * 1024.0))
280
                vcodec->bit_rate = num_val * 1024.0;
281
            else if(!strcmp(key, "audiodatarate") && acodec && 0 <= (int)(num_val * 1024.0))
282
                acodec->bit_rate = num_val * 1024.0;
283
        } else if (amf_type == AMF_DATA_TYPE_STRING)
284
            av_metadata_set2(&s->metadata, key, str_val, 0);
285
    }
286

    
287
    return 0;
288
}
289

    
290
static int flv_read_metabody(AVFormatContext *s, int64_t next_pos) {
291
    AMFDataType type;
292
    AVStream *stream, *astream, *vstream;
293
    AVIOContext *ioc;
294
    int i;
295
    char buffer[11]; //only needs to hold the string "onMetaData". Anything longer is something we don't want.
296

    
297
    astream = NULL;
298
    vstream = NULL;
299
    ioc = s->pb;
300

    
301
    //first object needs to be "onMetaData" string
302
    type = avio_r8(ioc);
303
    if(type != AMF_DATA_TYPE_STRING || amf_get_string(ioc, buffer, sizeof(buffer)) < 0 || strcmp(buffer, "onMetaData"))
304
        return -1;
305

    
306
    //find the streams now so that amf_parse_object doesn't need to do the lookup every time it is called.
307
    for(i = 0; i < s->nb_streams; i++) {
308
        stream = s->streams[i];
309
        if     (stream->codec->codec_type == AVMEDIA_TYPE_AUDIO) astream = stream;
310
        else if(stream->codec->codec_type == AVMEDIA_TYPE_VIDEO) vstream = stream;
311
    }
312

    
313
    //parse the second object (we want a mixed array)
314
    if(amf_parse_object(s, astream, vstream, buffer, next_pos, 0) < 0)
315
        return -1;
316

    
317
    return 0;
318
}
319

    
320
static AVStream *create_stream(AVFormatContext *s, int is_audio){
321
    AVStream *st = av_new_stream(s, is_audio);
322
    if (!st)
323
        return NULL;
324
    st->codec->codec_type = is_audio ? AVMEDIA_TYPE_AUDIO : AVMEDIA_TYPE_VIDEO;
325
    av_set_pts_info(st, 32, 1, 1000); /* 32 bit pts in ms */
326
    return st;
327
}
328

    
329
static int flv_read_header(AVFormatContext *s,
330
                           AVFormatParameters *ap)
331
{
332
    int offset, flags;
333

    
334
    avio_skip(s->pb, 4);
335
    flags = avio_r8(s->pb);
336
    /* old flvtool cleared this field */
337
    /* FIXME: better fix needed */
338
    if (!flags) {
339
        flags = FLV_HEADER_FLAG_HASVIDEO | FLV_HEADER_FLAG_HASAUDIO;
340
        av_log(s, AV_LOG_WARNING, "Broken FLV file, which says no streams present, this might fail\n");
341
    }
342

    
343
    if((flags & (FLV_HEADER_FLAG_HASVIDEO|FLV_HEADER_FLAG_HASAUDIO))
344
             != (FLV_HEADER_FLAG_HASVIDEO|FLV_HEADER_FLAG_HASAUDIO))
345
        s->ctx_flags |= AVFMTCTX_NOHEADER;
346

    
347
    if(flags & FLV_HEADER_FLAG_HASVIDEO){
348
        if(!create_stream(s, 0))
349
            return AVERROR(ENOMEM);
350
    }
351
    if(flags & FLV_HEADER_FLAG_HASAUDIO){
352
        if(!create_stream(s, 1))
353
            return AVERROR(ENOMEM);
354
    }
355

    
356
    offset = avio_rb32(s->pb);
357
    avio_seek(s->pb, offset, SEEK_SET);
358
    avio_skip(s->pb, 4);
359

    
360
    s->start_time = 0;
361

    
362
    return 0;
363
}
364

    
365
static int flv_get_extradata(AVFormatContext *s, AVStream *st, int size)
366
{
367
    av_free(st->codec->extradata);
368
    st->codec->extradata = av_mallocz(size + FF_INPUT_BUFFER_PADDING_SIZE);
369
    if (!st->codec->extradata)
370
        return AVERROR(ENOMEM);
371
    st->codec->extradata_size = size;
372
    avio_read(s->pb, st->codec->extradata, st->codec->extradata_size);
373
    return 0;
374
}
375

    
376
static int flv_read_packet(AVFormatContext *s, AVPacket *pkt)
377
{
378
    FLVContext *flv = s->priv_data;
379
    int ret, i, type, size, flags, is_audio;
380
    int64_t next, pos;
381
    int64_t dts, pts = AV_NOPTS_VALUE;
382
    AVStream *st = NULL;
383

    
384
 for(;;avio_skip(s->pb, 4)){ /* pkt size is repeated at end. skip it */
385
    pos = avio_tell(s->pb);
386
    type = avio_r8(s->pb);
387
    size = avio_rb24(s->pb);
388
    dts = avio_rb24(s->pb);
389
    dts |= avio_r8(s->pb) << 24;
390
//    av_log(s, AV_LOG_DEBUG, "type:%d, size:%d, dts:%d\n", type, size, dts);
391
    if (s->pb->eof_reached)
392
        return AVERROR_EOF;
393
    avio_skip(s->pb, 3); /* stream id, always 0 */
394
    flags = 0;
395

    
396
    if(size == 0)
397
        continue;
398

    
399
    next= size + avio_tell(s->pb);
400

    
401
    if (type == FLV_TAG_TYPE_AUDIO) {
402
        is_audio=1;
403
        flags = avio_r8(s->pb);
404
        size--;
405
    } else if (type == FLV_TAG_TYPE_VIDEO) {
406
        is_audio=0;
407
        flags = avio_r8(s->pb);
408
        size--;
409
        if ((flags & 0xf0) == 0x50) /* video info / command frame */
410
            goto skip;
411
    } else {
412
        if (type == FLV_TAG_TYPE_META && size > 13+1+4)
413
            flv_read_metabody(s, next);
414
        else /* skip packet */
415
            av_log(s, AV_LOG_DEBUG, "skipping flv packet: type %d, size %d, flags %d\n", type, size, flags);
416
    skip:
417
        avio_seek(s->pb, next, SEEK_SET);
418
        continue;
419
    }
420

    
421
    /* skip empty data packets */
422
    if (!size)
423
        continue;
424

    
425
    /* now find stream */
426
    for(i=0;i<s->nb_streams;i++) {
427
        st = s->streams[i];
428
        if (st->id == is_audio)
429
            break;
430
    }
431
    if(i == s->nb_streams){
432
        av_log(s, AV_LOG_ERROR, "invalid stream\n");
433
        st= create_stream(s, is_audio);
434
        s->ctx_flags &= ~AVFMTCTX_NOHEADER;
435
    }
436
//    av_log(s, AV_LOG_DEBUG, "%d %X %d \n", is_audio, flags, st->discard);
437
    if(  (st->discard >= AVDISCARD_NONKEY && !((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY ||         is_audio))
438
       ||(st->discard >= AVDISCARD_BIDIR  &&  ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_DISP_INTER && !is_audio))
439
       || st->discard >= AVDISCARD_ALL
440
       ){
441
        avio_seek(s->pb, next, SEEK_SET);
442
        continue;
443
    }
444
    if ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY)
445
        av_add_index_entry(st, pos, dts, size, 0, AVINDEX_KEYFRAME);
446
    break;
447
 }
448

    
449
    // if not streamed and no duration from metadata then seek to end to find the duration from the timestamps
450
    if(s->pb->seekable && (!s->duration || s->duration==AV_NOPTS_VALUE)){
451
        int size;
452
        const int64_t pos= avio_tell(s->pb);
453
        const int64_t fsize= avio_size(s->pb);
454
        avio_seek(s->pb, fsize-4, SEEK_SET);
455
        size= avio_rb32(s->pb);
456
        avio_seek(s->pb, fsize-3-size, SEEK_SET);
457
        if(size == avio_rb24(s->pb) + 11){
458
            uint32_t ts = avio_rb24(s->pb);
459
            ts |= avio_r8(s->pb) << 24;
460
            s->duration = ts * (int64_t)AV_TIME_BASE / 1000;
461
        }
462
        avio_seek(s->pb, pos, SEEK_SET);
463
    }
464

    
465
    if(is_audio){
466
        if(!st->codec->channels || !st->codec->sample_rate || !st->codec->bits_per_coded_sample) {
467
            st->codec->channels = (flags & FLV_AUDIO_CHANNEL_MASK) == FLV_STEREO ? 2 : 1;
468
            st->codec->sample_rate = (44100 << ((flags & FLV_AUDIO_SAMPLERATE_MASK) >> FLV_AUDIO_SAMPLERATE_OFFSET) >> 3);
469
            st->codec->bits_per_coded_sample = (flags & FLV_AUDIO_SAMPLESIZE_MASK) ? 16 : 8;
470
        }
471
        if(!st->codec->codec_id){
472
            flv_set_audio_codec(s, st, flags & FLV_AUDIO_CODECID_MASK);
473
        }
474
    }else{
475
        size -= flv_set_video_codec(s, st, flags & FLV_VIDEO_CODECID_MASK);
476
    }
477

    
478
    if (st->codec->codec_id == CODEC_ID_AAC ||
479
        st->codec->codec_id == CODEC_ID_H264) {
480
        int type = avio_r8(s->pb);
481
        size--;
482
        if (st->codec->codec_id == CODEC_ID_H264) {
483
            int32_t cts = (avio_rb24(s->pb)+0xff800000)^0xff800000; // sign extension
484
            pts = dts + cts;
485
            if (cts < 0) { // dts are wrong
486
                flv->wrong_dts = 1;
487
                av_log(s, AV_LOG_WARNING, "negative cts, previous timestamps might be wrong\n");
488
            }
489
            if (flv->wrong_dts)
490
                dts = AV_NOPTS_VALUE;
491
        }
492
        if (type == 0) {
493
            if ((ret = flv_get_extradata(s, st, size)) < 0)
494
                return ret;
495
            if (st->codec->codec_id == CODEC_ID_AAC) {
496
                MPEG4AudioConfig cfg;
497
                ff_mpeg4audio_get_config(&cfg, st->codec->extradata,
498
                                         st->codec->extradata_size);
499
                st->codec->channels = cfg.channels;
500
                if (cfg.ext_sample_rate)
501
                    st->codec->sample_rate = cfg.ext_sample_rate;
502
                else
503
                    st->codec->sample_rate = cfg.sample_rate;
504
                av_dlog(s, "mp4a config channels %d sample rate %d\n",
505
                        st->codec->channels, st->codec->sample_rate);
506
            }
507

    
508
            ret = AVERROR(EAGAIN);
509
            goto leave;
510
        }
511
    }
512

    
513
    /* skip empty data packets */
514
    if (!size) {
515
        ret = AVERROR(EAGAIN);
516
        goto leave;
517
    }
518

    
519
    ret= av_get_packet(s->pb, pkt, size);
520
    if (ret < 0) {
521
        return AVERROR(EIO);
522
    }
523
    /* note: we need to modify the packet size here to handle the last
524
       packet */
525
    pkt->size = ret;
526
    pkt->dts = dts;
527
    pkt->pts = pts == AV_NOPTS_VALUE ? dts : pts;
528
    pkt->stream_index = st->index;
529

    
530
    if (is_audio || ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY))
531
        pkt->flags |= AV_PKT_FLAG_KEY;
532

    
533
leave:
534
    avio_skip(s->pb, 4);
535
    return ret;
536
}
537

    
538
static int flv_read_seek(AVFormatContext *s, int stream_index,
539
    int64_t ts, int flags)
540
{
541
    return avio_seek_time(s->pb, stream_index, ts, flags);
542
}
543

    
544
#if 0 /* don't know enough to implement this */
545
static int flv_read_seek2(AVFormatContext *s, int stream_index,
546
    int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
547
{
548
    int ret = AVERROR(ENOSYS);
549

550
    if (ts - min_ts > (uint64_t)(max_ts - ts)) flags |= AVSEEK_FLAG_BACKWARD;
551

552
    if (!s->pb->seekable) {
553
        if (stream_index < 0) {
554
            stream_index = av_find_default_stream_index(s);
555
            if (stream_index < 0)
556
                return -1;
557

558
            /* timestamp for default must be expressed in AV_TIME_BASE units */
559
            ts = av_rescale_rnd(ts, 1000, AV_TIME_BASE,
560
                flags & AVSEEK_FLAG_BACKWARD ? AV_ROUND_DOWN : AV_ROUND_UP);
561
        }
562
        ret = avio_seek_time(s->pb, stream_index, ts, flags);
563
    }
564

565
    if (ret == AVERROR(ENOSYS))
566
        ret = av_seek_frame(s, stream_index, ts, flags);
567
    return ret;
568
}
569
#endif
570

    
571
AVInputFormat ff_flv_demuxer = {
572
    "flv",
573
    NULL_IF_CONFIG_SMALL("FLV format"),
574
    sizeof(FLVContext),
575
    flv_probe,
576
    flv_read_header,
577
    flv_read_packet,
578
    .read_seek = flv_read_seek,
579
#if 0
580
    .read_seek2 = flv_read_seek2,
581
#endif
582
    .extensions = "flv",
583
    .value = CODEC_ID_FLV1,
584
};