libavformat/flvenc.c

   1 /*
   2  * FLV muxer
   3  * Copyright (c) 2003 The FFmpeg Project.
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21 #include "avformat.h"
  22 #include "flv.h"
  23 #include "riff.h"
  24 #include "avc.h"
  25
  26 #undef NDEBUG
  27 #include <assert.h>
  28
  29 static const AVCodecTag flv_video_codec_ids[] = {
  30     {CODEC_ID_FLV1,    FLV_CODECID_H263  },
  31     {CODEC_ID_FLASHSV, FLV_CODECID_SCREEN},
  32     {CODEC_ID_VP6F,    FLV_CODECID_VP6   },
  33     {CODEC_ID_VP6,     FLV_CODECID_VP6   },
  34     {CODEC_ID_H264,    FLV_CODECID_H264  },
  35     {CODEC_ID_NONE,    0}
  36 };
  37
  38 static const AVCodecTag flv_audio_codec_ids[] = {
  39     {CODEC_ID_MP3,       FLV_CODECID_MP3    >> FLV_AUDIO_CODECID_OFFSET},
  40     {CODEC_ID_PCM_S8,    FLV_CODECID_PCM    >> FLV_AUDIO_CODECID_OFFSET},
  41     {CODEC_ID_PCM_S16BE, FLV_CODECID_PCM    >> FLV_AUDIO_CODECID_OFFSET},
  42     {CODEC_ID_PCM_S16LE, FLV_CODECID_PCM_LE >> FLV_AUDIO_CODECID_OFFSET},
  43     {CODEC_ID_ADPCM_SWF, FLV_CODECID_ADPCM  >> FLV_AUDIO_CODECID_OFFSET},
  44     {CODEC_ID_AAC,       FLV_CODECID_AAC    >> FLV_AUDIO_CODECID_OFFSET},
  45     {CODEC_ID_NELLYMOSER, FLV_CODECID_NELLYMOSER >> FLV_AUDIO_CODECID_OFFSET},
  46     {CODEC_ID_NONE,      0}
  47 };
  48
  49 typedef struct FLVContext {
  50     int reserved;
  51     int64_t duration_offset;
  52     int64_t filesize_offset;
  53     int64_t duration;
  54     int delay; ///< first dts delay for AVC
  55 } FLVContext;
  56
  57 static int get_audio_flags(AVCodecContext *enc){
  58     int flags = (enc->bits_per_coded_sample == 16) ? FLV_SAMPLESSIZE_16BIT : FLV_SAMPLESSIZE_8BIT;
  59
  60     if (enc->codec_id == CODEC_ID_AAC) // specs force these parameters
  61         return FLV_CODECID_AAC | FLV_SAMPLERATE_44100HZ | FLV_SAMPLESSIZE_16BIT | FLV_STEREO;
  62     else {
  63     switch (enc->sample_rate) {
  64         case    44100:
  65             flags |= FLV_SAMPLERATE_44100HZ;
  66             break;
  67         case    22050:
  68             flags |= FLV_SAMPLERATE_22050HZ;
  69             break;
  70         case    11025:
  71             flags |= FLV_SAMPLERATE_11025HZ;
  72             break;
  73         case     8000: //nellymoser only
  74         case     5512: //not mp3
  75             if(enc->codec_id != CODEC_ID_MP3){
  76                 flags |= FLV_SAMPLERATE_SPECIAL;
  77                 break;
  78             }
  79         default:
  80             av_log(enc, AV_LOG_ERROR, "flv does not support that sample rate, choose from (44100, 22050, 11025).\n");
  81             return -1;
  82     }
  83     }
  84
  85     if (enc->channels > 1) {
  86         flags |= FLV_STEREO;
  87     }
  88
  89     switch(enc->codec_id){
  90     case CODEC_ID_MP3:
  91         flags |= FLV_CODECID_MP3    | FLV_SAMPLESSIZE_16BIT;
  92         break;
  93     case CODEC_ID_PCM_S8:
  94         flags |= FLV_CODECID_PCM    | FLV_SAMPLESSIZE_8BIT;
  95         break;
  96     case CODEC_ID_PCM_S16BE:
  97         flags |= FLV_CODECID_PCM    | FLV_SAMPLESSIZE_16BIT;
  98         break;
  99     case CODEC_ID_PCM_S16LE:
 100         flags |= FLV_CODECID_PCM_LE | FLV_SAMPLESSIZE_16BIT;
 101         break;
 102     case CODEC_ID_ADPCM_SWF:
 103         flags |= FLV_CODECID_ADPCM | FLV_SAMPLESSIZE_16BIT;
 104         break;
 105     case CODEC_ID_NELLYMOSER:
 106         if (enc->sample_rate == 8000) {
 107             flags |= FLV_CODECID_NELLYMOSER_8KHZ_MONO | FLV_SAMPLESSIZE_16BIT;
 108         } else {
 109             flags |= FLV_CODECID_NELLYMOSER | FLV_SAMPLESSIZE_16BIT;
 110         }
 111         break;
 112     case 0:
 113         flags |= enc->codec_tag<<4;
 114         break;
 115     default:
 116         av_log(enc, AV_LOG_ERROR, "codec not compatible with flv\n");
 117         return -1;
 118     }
 119
 120     return flags;
 121 }
 122
 123 static void put_amf_string(ByteIOContext *pb, const char *str)
 124 {
 125     size_t len = strlen(str);
 126     put_be16(pb, len);
 127     put_buffer(pb, str, len);
 128 }
 129
 130 static void put_amf_double(ByteIOContext *pb, double d)
 131 {
 132     put_byte(pb, AMF_DATA_TYPE_NUMBER);
 133     put_be64(pb, av_dbl2int(d));
 134 }
 135
 136 static void put_amf_bool(ByteIOContext *pb, int b) {
 137     put_byte(pb, AMF_DATA_TYPE_BOOL);
 138     put_byte(pb, !!b);
 139 }
 140
 141 static int flv_write_header(AVFormatContext *s)
 142 {
 143     ByteIOContext *pb = s->pb;
 144     FLVContext *flv = s->priv_data;
 145     AVCodecContext *audio_enc = NULL, *video_enc = NULL;
 146     int i;
 147     double framerate = 0.0;
 148     int metadata_size_pos, data_size;
 149
 150     for(i=0; i<s->nb_streams; i++){
 151         AVCodecContext *enc = s->streams[i]->codec;
 152         if (enc->codec_type == CODEC_TYPE_VIDEO) {
 153             if (s->streams[i]->r_frame_rate.den && s->streams[i]->r_frame_rate.num) {
 154                 framerate = av_q2d(s->streams[i]->r_frame_rate);
 155             } else {
 156                 framerate = 1/av_q2d(s->streams[i]->codec->time_base);
 157             }
 158             video_enc = enc;
 159             if(enc->codec_tag == 0) {
 160                 av_log(enc, AV_LOG_ERROR, "video codec not compatible with flv\n");
 161                 return -1;
 162             }
 163         } else {
 164             audio_enc = enc;
 165             if(get_audio_flags(enc)<0)
 166                 return -1;
 167         }
 168         av_set_pts_info(s->streams[i], 32, 1, 1000); /* 32 bit pts in ms */
 169     }
 170     put_tag(pb,"FLV");
 171     put_byte(pb,1);
 172     put_byte(pb,   FLV_HEADER_FLAG_HASAUDIO * !!audio_enc
 173                  + FLV_HEADER_FLAG_HASVIDEO * !!video_enc);
 174     put_be32(pb,9);
 175     put_be32(pb,0);
 176
 177     for(i=0; i<s->nb_streams; i++){
 178         if(s->streams[i]->codec->codec_tag == 5){
 179             put_byte(pb,8); // message type
 180             put_be24(pb,0); // include flags
 181             put_be24(pb,0); // time stamp
 182             put_be32(pb,0); // reserved
 183             put_be32(pb,11); // size
 184             flv->reserved=5;
 185         }
 186     }
 187
 188     /* write meta_tag */
 189     put_byte(pb, 18);         // tag type META
 190     metadata_size_pos= url_ftell(pb);
 191     put_be24(pb, 0);          // size of data part (sum of all parts below)
 192     put_be24(pb, 0);          // time stamp
 193     put_be32(pb, 0);          // reserved
 194
 195     /* now data of data_size size */
 196
 197     /* first event name as a string */
 198     put_byte(pb, AMF_DATA_TYPE_STRING);
 199     put_amf_string(pb, "onMetaData"); // 12 bytes
 200
 201     /* mixed array (hash) with size and string/type/data tuples */
 202     put_byte(pb, AMF_DATA_TYPE_MIXEDARRAY);
 203     put_be32(pb, 5*!!video_enc + 4*!!audio_enc + 2); // +2 for duration and file size
 204
 205     put_amf_string(pb, "duration");
 206     flv->duration_offset= url_ftell(pb);
 207     put_amf_double(pb, 0); // delayed write
 208
 209     if(video_enc){
 210         put_amf_string(pb, "width");
 211         put_amf_double(pb, video_enc->width);
 212
 213         put_amf_string(pb, "height");
 214         put_amf_double(pb, video_enc->height);
 215
 216         put_amf_string(pb, "videodatarate");
 217         put_amf_double(pb, s->bit_rate / 1024.0);
 218
 219         put_amf_string(pb, "framerate");
 220         put_amf_double(pb, framerate);
 221
 222         put_amf_string(pb, "videocodecid");
 223         put_amf_double(pb, video_enc->codec_tag);
 224     }
 225
 226     if(audio_enc){
 227         put_amf_string(pb, "audiosamplerate");
 228         put_amf_double(pb, audio_enc->sample_rate);
 229
 230         put_amf_string(pb, "audiosamplesize");
 231         put_amf_double(pb, audio_enc->codec_id == CODEC_ID_PCM_S8 ? 8 : 16);
 232
 233         put_amf_string(pb, "stereo");
 234         put_amf_bool(pb, audio_enc->channels == 2);
 235
 236         put_amf_string(pb, "audiocodecid");
 237         put_amf_double(pb, audio_enc->codec_tag);
 238     }
 239
 240     put_amf_string(pb, "filesize");
 241     flv->filesize_offset= url_ftell(pb);
 242     put_amf_double(pb, 0); // delayed write
 243
 244     put_amf_string(pb, "");
 245     put_byte(pb, AMF_END_OF_OBJECT);
 246
 247     /* write total size of tag */
 248     data_size= url_ftell(pb) - metadata_size_pos - 10;
 249     url_fseek(pb, metadata_size_pos, SEEK_SET);
 250     put_be24(pb, data_size);
 251     url_fseek(pb, data_size + 10 - 3, SEEK_CUR);
 252     put_be32(pb, data_size + 11);
 253
 254     for (i = 0; i < s->nb_streams; i++) {
 255         AVCodecContext *enc = s->streams[i]->codec;
 256         if (enc->codec_id == CODEC_ID_AAC || enc->codec_id == CODEC_ID_H264) {
 257             int64_t pos;
 258             put_byte(pb, enc->codec_type == CODEC_TYPE_VIDEO ?
 259                      FLV_TAG_TYPE_VIDEO : FLV_TAG_TYPE_AUDIO);
 260             put_be24(pb, 0); // size patched later
 261             put_be24(pb, 0); // ts
 262             put_byte(pb, 0); // ts ext
 263             put_be24(pb, 0); // streamid
 264             pos = url_ftell(pb);
 265             if (enc->codec_id == CODEC_ID_AAC) {
 266                 put_byte(pb, get_audio_flags(enc));
 267                 put_byte(pb, 0); // AAC sequence header
 268                 put_buffer(pb, enc->extradata, enc->extradata_size);
 269             } else {
 270                 put_byte(pb, enc->codec_tag | FLV_FRAME_KEY); // flags
 271                 put_byte(pb, 0); // AVC sequence header
 272                 put_be24(pb, 0); // composition time
 273                 ff_isom_write_avcc(pb, enc->extradata, enc->extradata_size);
 274             }
 275             data_size = url_ftell(pb) - pos;
 276             url_fseek(pb, -data_size - 10, SEEK_CUR);
 277             put_be24(pb, data_size);
 278             url_fseek(pb, data_size + 10 - 3, SEEK_CUR);
 279             put_be32(pb, data_size + 11); // previous tag size
 280         }
 281     }
 282
 283     return 0;
 284 }
 285
 286 static int flv_write_trailer(AVFormatContext *s)
 287 {
 288     int64_t file_size;
 289
 290     ByteIOContext *pb = s->pb;
 291     FLVContext *flv = s->priv_data;
 292
 293     file_size = url_ftell(pb);
 294
 295     /* update informations */
 296     url_fseek(pb, flv->duration_offset, SEEK_SET);
 297     put_amf_double(pb, flv->duration / (double)1000);
 298     url_fseek(pb, flv->filesize_offset, SEEK_SET);
 299     put_amf_double(pb, file_size);
 300
 301     url_fseek(pb, file_size, SEEK_SET);
 302     return 0;
 303 }
 304
 305 static int flv_write_packet(AVFormatContext *s, AVPacket *pkt)
 306 {
 307     ByteIOContext *pb = s->pb;
 308     AVCodecContext *enc = s->streams[pkt->stream_index]->codec;
 309     FLVContext *flv = s->priv_data;
 310     unsigned ts;
 311     int size= pkt->size;
 312     int flags, flags_size;
 313
 314 //    av_log(s, AV_LOG_DEBUG, "type:%d pts: %"PRId64" size:%d\n", enc->codec_type, timestamp, size);
 315
 316     if(enc->codec_id == CODEC_ID_VP6 || enc->codec_id == CODEC_ID_VP6F ||
 317        enc->codec_id == CODEC_ID_AAC)
 318         flags_size= 2;
 319     else if(enc->codec_id == CODEC_ID_H264)
 320         flags_size= 5;
 321     else
 322         flags_size= 1;
 323
 324     if (enc->codec_type == CODEC_TYPE_VIDEO) {
 325         put_byte(pb, FLV_TAG_TYPE_VIDEO);
 326
 327         flags = enc->codec_tag;
 328         if(flags == 0) {
 329             av_log(enc, AV_LOG_ERROR, "video codec %X not compatible with flv\n",enc->codec_id);
 330             return -1;
 331         }
 332
 333         flags |= pkt->flags & PKT_FLAG_KEY ? FLV_FRAME_KEY : FLV_FRAME_INTER;
 334     } else {
 335         assert(enc->codec_type == CODEC_TYPE_AUDIO);
 336         flags = get_audio_flags(enc);
 337
 338         assert(size);
 339
 340         put_byte(pb, FLV_TAG_TYPE_AUDIO);
 341     }
 342
 343     if (enc->codec_id == CODEC_ID_H264 &&
 344         /* check if extradata looks like mp4 formated */
 345         enc->extradata_size > 0 && *(uint8_t*)enc->extradata != 1) {
 346         if (ff_avc_parse_nal_units(pkt->data, &pkt->data, &pkt->size) < 0)
 347             return -1;
 348         assert(pkt->size);
 349         size = pkt->size;
 350         /* cast needed to get negative value */
 351         if (!flv->delay && pkt->dts < 0)
 352             flv->delay = -pkt->dts;
 353     }
 354
 355     ts = pkt->dts + flv->delay; // add delay to force positive dts
 356     put_be24(pb,size + flags_size);
 357     put_be24(pb,ts);
 358     put_byte(pb,(ts >> 24) & 0x7F); // timestamps are 32bits _signed_
 359     put_be24(pb,flv->reserved);
 360     put_byte(pb,flags);
 361     if (enc->codec_id == CODEC_ID_VP6)
 362         put_byte(pb,0);
 363     if (enc->codec_id == CODEC_ID_VP6F)
 364         put_byte(pb, enc->extradata_size ? enc->extradata[0] : 0);
 365     else if (enc->codec_id == CODEC_ID_AAC)
 366         put_byte(pb,1); // AAC raw
 367     else if (enc->codec_id == CODEC_ID_H264) {
 368         put_byte(pb,1); // AVC NALU
 369         put_be24(pb,pkt->pts - pkt->dts);
 370     }
 371     put_buffer(pb, pkt->data, size);
 372     put_be32(pb,size+flags_size+11); // previous tag size
 373     flv->duration = FFMAX(flv->duration, pkt->pts + flv->delay + pkt->duration);
 374
 375     put_flush_packet(pb);
 376     return 0;
 377 }
 378
 379 AVOutputFormat flv_muxer = {
 380     "flv",
 381     NULL_IF_CONFIG_SMALL("FLV format"),
 382     "video/x-flv",
 383     "flv",
 384     sizeof(FLVContext),
 385 #ifdef CONFIG_LIBMP3LAME
 386     CODEC_ID_MP3,
 387 #else // CONFIG_LIBMP3LAME
 388     CODEC_ID_ADPCM_SWF,
 389 #endif // CONFIG_LIBMP3LAME
 390     CODEC_ID_FLV1,
 391     flv_write_header,
 392     flv_write_packet,
 393     flv_write_trailer,
 394     .codec_tag= (const AVCodecTag* const []){flv_video_codec_ids, flv_audio_codec_ids, 0},
 395     .flags= AVFMT_GLOBALHEADER,
 396 };