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ffmpeg / libavformat / flvdec.c @ 756fb7fe

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1 d4f5d74a Garrick Meeker
/*
2 7fbde343 Aurelien Jacobs
 * FLV demuxer
3 d4f5d74a Garrick Meeker
 * Copyright (c) 2003 The FFmpeg Project.
4
 *
5 b78e7197 Diego Biurrun
 * This file is part of FFmpeg.
6
 *
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 * FFmpeg is free software; you can redistribute it and/or
8 d4f5d74a Garrick Meeker
 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
10 b78e7197 Diego Biurrun
 * version 2.1 of the License, or (at your option) any later version.
11 d4f5d74a Garrick Meeker
 *
12 b78e7197 Diego Biurrun
 * FFmpeg is distributed in the hope that it will be useful,
13 d4f5d74a Garrick Meeker
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15
 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
18 b78e7197 Diego Biurrun
 * License along with FFmpeg; if not, write to the Free Software
19 5509bffa Diego Biurrun
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 246f86a4 Aurelien Jacobs
 *
21
 *
22
 * This demuxer will generate a 1 byte extradata for VP6F content.
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 * It is composed of:
24
 *  - upper 4bits: difference between encoded width and visible width
25
 *  - lower 4bits: difference between encoded height and visible height
26 d4f5d74a Garrick Meeker
 */
27
#include "avformat.h"
28 6cac3a3b Allan Hsu
#include "flv.h"
29 d4f5d74a Garrick Meeker
30
static int flv_probe(AVProbeData *p)
31
{
32
    const uint8_t *d;
33
34
    d = p->buf;
35 74248229 Michael Niedermayer
    if (d[0] == 'F' && d[1] == 'L' && d[2] == 'V' && d[3] < 5 && d[5]==0) {
36
        return AVPROBE_SCORE_MAX;
37 d4f5d74a Garrick Meeker
    }
38
    return 0;
39
}
40
41 428cc588 Allan Hsu
static void flv_set_audio_codec(AVFormatContext *s, AVStream *astream, int flv_codecid) {
42
    AVCodecContext *acodec = astream->codec;
43
    switch(flv_codecid) {
44
        //no distinction between S16 and S8 PCM codec flags
45
        case FLV_CODECID_PCM_BE:
46
            acodec->codec_id = acodec->bits_per_sample == 8 ? CODEC_ID_PCM_S8 : CODEC_ID_PCM_S16BE; break;
47
        case FLV_CODECID_PCM_LE:
48
            acodec->codec_id = acodec->bits_per_sample == 8 ? CODEC_ID_PCM_S8 : CODEC_ID_PCM_S16LE; break;
49
        case FLV_CODECID_ADPCM: acodec->codec_id = CODEC_ID_ADPCM_SWF;                              break;
50 57004ff1 Aurelien Jacobs
        case FLV_CODECID_MP3  : acodec->codec_id = CODEC_ID_MP3      ; astream->need_parsing = AVSTREAM_PARSE_FULL; break;
51 428cc588 Allan Hsu
        case FLV_CODECID_NELLYMOSER_8HZ_MONO:
52
            acodec->sample_rate = 8000; //in case metadata does not otherwise declare samplerate
53
        case FLV_CODECID_NELLYMOSER:
54
        default:
55
            av_log(s, AV_LOG_INFO, "Unsupported audio codec (%x)\n", flv_codecid >> FLV_AUDIO_CODECID_OFFSET);
56
            acodec->codec_tag = flv_codecid >> FLV_AUDIO_CODECID_OFFSET;
57
    }
58
}
59
60
static int flv_set_video_codec(AVFormatContext *s, AVStream *vstream, int flv_codecid) {
61
    AVCodecContext *vcodec = vstream->codec;
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    switch(flv_codecid) {
63
        case FLV_CODECID_H263  : vcodec->codec_id = CODEC_ID_FLV1   ; break;
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        case FLV_CODECID_SCREEN: vcodec->codec_id = CODEC_ID_FLASHSV; break;
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        case FLV_CODECID_VP6   : vcodec->codec_id = CODEC_ID_VP6F   ;
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            if(vcodec->extradata_size != 1) {
67
                vcodec->extradata_size = 1;
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                vcodec->extradata = av_malloc(1);
69
            }
70
            vcodec->extradata[0] = get_byte(&s->pb);
71
            return 1; // 1 byte body size adjustment for flv_read_packet()
72
        default:
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            av_log(s, AV_LOG_INFO, "Unsupported video codec (%x)\n", flv_codecid);
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            vcodec->codec_tag = flv_codecid;
75
    }
76
77
    return 0;
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}
79
80 896bcd2e Michael Niedermayer
static int amf_get_string(ByteIOContext *ioc, char *buffer, int buffsize) {
81 759dd138 Michael Niedermayer
    int length = get_be16(ioc);
82 896bcd2e Michael Niedermayer
    if(length >= buffsize) {
83
        url_fskip(ioc, length);
84 759dd138 Michael Niedermayer
        return -1;
85 896bcd2e Michael Niedermayer
    }
86
87
    get_buffer(ioc, buffer, length);
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    buffer[length] = '\0';
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    return length;
92
}
93
94 428cc588 Allan Hsu
static int amf_parse_object(AVFormatContext *s, AVStream *astream, AVStream *vstream, const char *key, unsigned int max_pos, int depth) {
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    AVCodecContext *acodec, *vcodec;
96
    ByteIOContext *ioc;
97
    AMFDataType amf_type;
98
    char str_val[256];
99
    double num_val;
100
101
    num_val = 0;
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    ioc = &s->pb;
103
104
    amf_type = get_byte(ioc);
105
106
    switch(amf_type) {
107
        case AMF_DATA_TYPE_NUMBER:
108
            num_val = av_int2dbl(get_be64(ioc)); break;
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        case AMF_DATA_TYPE_BOOL:
110
            num_val = get_byte(ioc); break;
111
        case AMF_DATA_TYPE_STRING:
112
            if(amf_get_string(ioc, str_val, sizeof(str_val)) < 0)
113
                return -1;
114
            break;
115
        case AMF_DATA_TYPE_OBJECT: {
116
            unsigned int keylen;
117
118
            while(url_ftell(ioc) < max_pos - 2 && (keylen = get_be16(ioc))) {
119
                url_fskip(ioc, keylen); //skip key string
120
                if(amf_parse_object(s, NULL, NULL, NULL, max_pos, depth + 1) < 0)
121
                    return -1; //if we couldn't skip, bomb out.
122
            }
123
            if(get_byte(ioc) != AMF_END_OF_OBJECT)
124
                return -1;
125
        }
126
            break;
127
        case AMF_DATA_TYPE_NULL:
128
        case AMF_DATA_TYPE_UNDEFINED:
129
        case AMF_DATA_TYPE_UNSUPPORTED:
130
            break; //these take up no additional space
131
        case AMF_DATA_TYPE_MIXEDARRAY:
132
            url_fskip(ioc, 4); //skip 32-bit max array index
133
            while(url_ftell(ioc) < max_pos - 2 && amf_get_string(ioc, str_val, sizeof(str_val)) > 0) {
134
                //this is the only case in which we would want a nested parse to not skip over the object
135
                if(amf_parse_object(s, astream, vstream, str_val, max_pos, depth + 1) < 0)
136
                    return -1;
137
            }
138
            if(get_byte(ioc) != AMF_END_OF_OBJECT)
139
                return -1;
140
            break;
141
        case AMF_DATA_TYPE_ARRAY: {
142
            unsigned int arraylen, i;
143
144
            arraylen = get_be32(ioc);
145
            for(i = 0; i < arraylen && url_ftell(ioc) < max_pos - 1; i++) {
146
                if(amf_parse_object(s, NULL, NULL, NULL, max_pos, depth + 1) < 0)
147
                    return -1; //if we couldn't skip, bomb out.
148
            }
149
        }
150
            break;
151
        case AMF_DATA_TYPE_DATE:
152
            url_fskip(ioc, 8 + 2); //timestamp (double) and UTC offset (int16)
153
            break;
154
        default: //unsupported type, we couldn't skip
155
            return -1;
156
    }
157
158
    if(depth == 1 && key) { //only look for metadata values when we are not nested and key != NULL
159
        acodec = astream ? astream->codec : NULL;
160
        vcodec = vstream ? vstream->codec : NULL;
161
162
        if(amf_type == AMF_DATA_TYPE_BOOL) {
163
            if(!strcmp(key, "stereo") && acodec) acodec->channels = num_val > 0 ? 2 : 1;
164
        } else if(amf_type == AMF_DATA_TYPE_NUMBER) {
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            if(!strcmp(key, "duration")) s->duration = num_val * AV_TIME_BASE;
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//            else if(!strcmp(key, "width")  && vcodec && num_val > 0) vcodec->width  = num_val;
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//            else if(!strcmp(key, "height") && vcodec && num_val > 0) vcodec->height = num_val;
168 428cc588 Allan Hsu
            else if(!strcmp(key, "audiocodecid") && acodec) flv_set_audio_codec(s, astream, (int)num_val << FLV_AUDIO_CODECID_OFFSET);
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            else if(!strcmp(key, "videocodecid") && vcodec) flv_set_video_codec(s, vstream, (int)num_val);
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            else if(!strcmp(key, "audiosamplesize") && acodec && num_val >= 0) {
171
                acodec->bits_per_sample = num_val;
172
                //we may have to rewrite a previously read codecid because FLV only marks PCM endianness.
173
                if(num_val == 8 && (acodec->codec_id == CODEC_ID_PCM_S16BE || acodec->codec_id == CODEC_ID_PCM_S16LE))
174
                    acodec->codec_id = CODEC_ID_PCM_S8;
175
            }
176
            else if(!strcmp(key, "audiosamplerate") && acodec && num_val >= 0) {
177
                //some tools, like FLVTool2, write consistently approximate metadata sample rates
178
                switch((int)num_val) {
179
                    case 44000: acodec->sample_rate = 44100  ; break;
180
                    case 22000: acodec->sample_rate = 22050  ; break;
181
                    case 11000: acodec->sample_rate = 11025  ; break;
182
                    case 5000 : acodec->sample_rate = 5512   ; break;
183
                    default   : acodec->sample_rate = num_val;
184
                }
185
            }
186
        }
187
    }
188
189
    return 0;
190
}
191
192
static int flv_read_metabody(AVFormatContext *s, unsigned int next_pos) {
193
    AMFDataType type;
194
    AVStream *stream, *astream, *vstream;
195
    ByteIOContext *ioc;
196
    int i, keylen;
197
    char buffer[11]; //only needs to hold the string "onMetaData". Anything longer is something we don't want.
198
199
    astream = NULL;
200
    vstream = NULL;
201
    keylen = 0;
202
    ioc = &s->pb;
203
204
    //first object needs to be "onMetaData" string
205
    type = get_byte(ioc);
206
    if(type != AMF_DATA_TYPE_STRING || amf_get_string(ioc, buffer, sizeof(buffer)) < 0 || strcmp(buffer, "onMetaData"))
207
        return -1;
208
209
    //find the streams now so that amf_parse_object doesn't need to do the lookup every time it is called.
210
    for(i = 0; i < s->nb_streams; i++) {
211
        stream = s->streams[i];
212
        if     (stream->codec->codec_type == CODEC_TYPE_AUDIO) astream = stream;
213
        else if(stream->codec->codec_type == CODEC_TYPE_VIDEO) vstream = stream;
214
    }
215
216
    //parse the second object (we want a mixed array)
217
    if(amf_parse_object(s, astream, vstream, buffer, next_pos, 0) < 0)
218
        return -1;
219
220
    return 0;
221
}
222
223 d4f5d74a Garrick Meeker
static int flv_read_header(AVFormatContext *s,
224
                           AVFormatParameters *ap)
225
{
226 15f14fc7 Michael Niedermayer
    int offset, flags;
227 4eb0c665 Michael Niedermayer
    AVStream *st;
228 d4f5d74a Garrick Meeker
229
    url_fskip(&s->pb, 4);
230
    flags = get_byte(&s->pb);
231 031311cb Alex Beregszaszi
    /* old flvtool cleared this field */
232
    /* FIXME: better fix needed */
233
    if (!flags) {
234
        flags = FLV_HEADER_FLAG_HASVIDEO | FLV_HEADER_FLAG_HASAUDIO;
235
        av_log(s, AV_LOG_WARNING, "Broken FLV file, which says no streams present, this might fail\n");
236
    }
237 d4f5d74a Garrick Meeker
238 4eb0c665 Michael Niedermayer
    if(flags & FLV_HEADER_FLAG_HASVIDEO){
239
        st = av_new_stream(s, 0);
240
        if (!st)
241
            return AVERROR_NOMEM;
242
        st->codec->codec_type = CODEC_TYPE_VIDEO;
243
        av_set_pts_info(st, 24, 1, 1000); /* 24 bit pts in ms */
244
    }
245
    if(flags & FLV_HEADER_FLAG_HASAUDIO){
246
        st = av_new_stream(s, 1);
247
        if (!st)
248
            return AVERROR_NOMEM;
249
        st->codec->codec_type = CODEC_TYPE_AUDIO;
250
        av_set_pts_info(st, 24, 1, 1000); /* 24 bit pts in ms */
251
    }
252
253 d4f5d74a Garrick Meeker
    offset = get_be32(&s->pb);
254
    url_fseek(&s->pb, offset, SEEK_SET);
255
256 aeb20f7f Nazo
    s->start_time = 0;
257
258 d4f5d74a Garrick Meeker
    return 0;
259
}
260
261
static int flv_read_packet(AVFormatContext *s, AVPacket *pkt)
262
{
263 aeb20f7f Nazo
    int ret, i, type, size, pts, flags, is_audio, next, pos;
264 923bd441 Alex Beregszaszi
    AVStream *st = NULL;
265 115329f1 Diego Biurrun
266 068f2a22 Michael Niedermayer
 for(;;){
267 aeb20f7f Nazo
    pos = url_ftell(&s->pb);
268 d4f5d74a Garrick Meeker
    url_fskip(&s->pb, 4); /* size of previous packet */
269
    type = get_byte(&s->pb);
270
    size = get_be24(&s->pb);
271
    pts = get_be24(&s->pb);
272 92a26775 Michael Niedermayer
//    av_log(s, AV_LOG_DEBUG, "type:%d, size:%d, pts:%d\n", type, size, pts);
273 d4f5d74a Garrick Meeker
    if (url_feof(&s->pb))
274 0bd586c5 Mike Melanson
        return AVERROR_IO;
275 d4f5d74a Garrick Meeker
    url_fskip(&s->pb, 4); /* reserved */
276
    flags = 0;
277 115329f1 Diego Biurrun
278 068f2a22 Michael Niedermayer
    if(size == 0)
279
        continue;
280 115329f1 Diego Biurrun
281 dd9f5916 Michael Niedermayer
    next= size + url_ftell(&s->pb);
282
283 6cac3a3b Allan Hsu
    if (type == FLV_TAG_TYPE_AUDIO) {
284 068f2a22 Michael Niedermayer
        is_audio=1;
285 d4f5d74a Garrick Meeker
        flags = get_byte(&s->pb);
286 6cac3a3b Allan Hsu
    } else if (type == FLV_TAG_TYPE_VIDEO) {
287 068f2a22 Michael Niedermayer
        is_audio=0;
288 d4f5d74a Garrick Meeker
        flags = get_byte(&s->pb);
289
    } else {
290 428cc588 Allan Hsu
        if (type == FLV_TAG_TYPE_META && size > 13+1+4)
291
            flv_read_metabody(s, next);
292
        else /* skip packet */
293
            av_log(s, AV_LOG_ERROR, "skipping flv packet: type %d, size %d, flags %d\n", type, size, flags);
294 dd9f5916 Michael Niedermayer
        url_fseek(&s->pb, next, SEEK_SET);
295 068f2a22 Michael Niedermayer
        continue;
296 d4f5d74a Garrick Meeker
    }
297
298
    /* now find stream */
299
    for(i=0;i<s->nb_streams;i++) {
300
        st = s->streams[i];
301 068f2a22 Michael Niedermayer
        if (st->id == is_audio)
302
            break;
303 d4f5d74a Garrick Meeker
    }
304 068f2a22 Michael Niedermayer
    if(i == s->nb_streams){
305 4eb0c665 Michael Niedermayer
        av_log(NULL, AV_LOG_ERROR, "invalid stream\n");
306
        url_fseek(&s->pb, next, SEEK_SET);
307
        continue;
308 6ed08157 Michael Niedermayer
    }
309 f3356e9c Michael Niedermayer
//    av_log(NULL, AV_LOG_DEBUG, "%d %X %d \n", is_audio, flags, st->discard);
310 6cac3a3b Allan Hsu
    if(  (st->discard >= AVDISCARD_NONKEY && !((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY ||         is_audio))
311
       ||(st->discard >= AVDISCARD_BIDIR  &&  ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_DISP_INTER && !is_audio))
312 f3356e9c Michael Niedermayer
       || st->discard >= AVDISCARD_ALL
313
       ){
314 dd9f5916 Michael Niedermayer
        url_fseek(&s->pb, next, SEEK_SET);
315 b9866ebc Michael Niedermayer
        continue;
316
    }
317 6cac3a3b Allan Hsu
    if ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY)
318 aeb20f7f Nazo
        av_add_index_entry(st, pos, pts, size, 0, AVINDEX_KEYFRAME);
319 068f2a22 Michael Niedermayer
    break;
320
 }
321
322 15f14fc7 Michael Niedermayer
    // if not streamed and no duration from metadata then seek to end to find the duration from the timestamps
323
    if(!url_is_streamed(&s->pb) && s->duration==AV_NOPTS_VALUE){
324
        int size;
325
        const int pos= url_ftell(&s->pb);
326
        const int fsize= url_fsize(&s->pb);
327
        url_fseek(&s->pb, fsize-4, SEEK_SET);
328
        size= get_be32(&s->pb);
329
        url_fseek(&s->pb, fsize-3-size, SEEK_SET);
330
        if(size == get_be24(&s->pb) + 11){
331
            s->duration= get_be24(&s->pb) * (int64_t)AV_TIME_BASE / 1000;
332
        }
333
        url_fseek(&s->pb, pos, SEEK_SET);
334
    }
335
336 068f2a22 Michael Niedermayer
    if(is_audio){
337 428cc588 Allan Hsu
        if(!st->codec->sample_rate || !st->codec->bits_per_sample || (!st->codec->codec_id && !st->codec->codec_tag)) {
338 6cac3a3b Allan Hsu
            st->codec->channels = (flags & FLV_AUDIO_CHANNEL_MASK) == FLV_STEREO ? 2 : 1;
339
            if((flags & FLV_AUDIO_CODECID_MASK) == FLV_CODECID_NELLYMOSER_8HZ_MONO)
340 01f4895c Michael Niedermayer
                st->codec->sample_rate= 8000;
341 068f2a22 Michael Niedermayer
            else
342 6cac3a3b Allan Hsu
                st->codec->sample_rate = (44100 << ((flags & FLV_AUDIO_SAMPLERATE_MASK) >> FLV_AUDIO_SAMPLERATE_OFFSET) >> 3);
343
            st->codec->bits_per_sample = (flags & FLV_AUDIO_SAMPLESIZE_MASK) ? 16 : 8;
344 428cc588 Allan Hsu
            flv_set_audio_codec(s, st, flags & FLV_AUDIO_CODECID_MASK);
345 068f2a22 Michael Niedermayer
        }
346
    }else{
347 428cc588 Allan Hsu
        size -= flv_set_video_codec(s, st, flags & FLV_VIDEO_CODECID_MASK);
348 bb01a3f0 Michael Niedermayer
    }
349
350 dd9f5916 Michael Niedermayer
    ret= av_get_packet(&s->pb, pkt, size - 1);
351 d4f5d74a Garrick Meeker
    if (ret <= 0) {
352 0bd586c5 Mike Melanson
        return AVERROR_IO;
353 d4f5d74a Garrick Meeker
    }
354
    /* note: we need to modify the packet size here to handle the last
355
       packet */
356
    pkt->size = ret;
357
    pkt->pts = pts;
358
    pkt->stream_index = st->index;
359 115329f1 Diego Biurrun
360 6cac3a3b Allan Hsu
    if (is_audio || ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY))
361 bb270c08 Diego Biurrun
        pkt->flags |= PKT_FLAG_KEY;
362 115329f1 Diego Biurrun
363 d4f5d74a Garrick Meeker
    return ret;
364
}
365
366
static int flv_read_close(AVFormatContext *s)
367
{
368
    return 0;
369
}
370
371 aeb20f7f Nazo
static int flv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
372
{
373
    AVStream *st = s->streams[stream_index];
374
    int index = av_index_search_timestamp(st, timestamp, flags);
375
    if (index < 0)
376
        return -1;
377
    url_fseek(&s->pb, st->index_entries[index].pos, SEEK_SET);
378
379
    return 0;
380
}
381
382 d2a067d1 Måns Rullgård
AVInputFormat flv_demuxer = {
383 d4f5d74a Garrick Meeker
    "flv",
384
    "flv format",
385
    0,
386
    flv_probe,
387
    flv_read_header,
388
    flv_read_packet,
389
    flv_read_close,
390 aeb20f7f Nazo
    flv_read_seek,
391 d4f5d74a Garrick Meeker
    .extensions = "flv",
392
    .value = CODEC_ID_FLV1,
393
};