int av_reduce(int *dst_nom, int *dst_den, int64_t nom, int64_t den, int64_t max){ AVRational a0={0,1}, a1={1,0}; int sign= (nom<0) ^ (den<0); int64_t gcd= ff_gcd(ABS(nom), ABS(den)); nom = ABS(nom)/gcd; den = ABS(den)/gcd; if(nom<=max && den<=max){ a1= _AVRational((int)nom,(int)den); //Picard den=0; } while(den){ int64_t x = nom / den; int64_t next_den= nom - den*x; int64_t a2n= x*a1.num + a0.num; int64_t a2d= x*a1.den + a0.den; if(a2n > max || a2d > max) break; a0= a1; a1= _AVRational((int)a2n, (int)a2d); //Picard nom= den; den= next_den; } assert(ff_gcd(a1.num, a1.den) == 1); *dst_nom = sign ? -a1.num : a1.num; *dst_den = a1.den; return den==0; }
/** * Routine to correct a possibly erroneous framerate being fed to us. * XviD currently chokes on framerates where the ticks per frame is * extremely large. This function works to correct problems in this area * by estimating a new framerate and taking the simpler fraction of * the two presented. * * @param avctx Context that contains the framerate to correct. */ void xvid_correct_framerate(AVCodecContext *avctx) { int frate, fbase; int est_frate, est_fbase; int gcd; float est_fps, fps; frate = avctx->time_base.den; fbase = avctx->time_base.num; gcd = ff_gcd(frate, fbase); if( gcd > 1 ) { frate /= gcd; fbase /= gcd; } if( frate <= 65000 && fbase <= 65000 ) { avctx->time_base.den = frate; avctx->time_base.num = fbase; return; } fps = (float)frate / (float)fbase; est_fps = roundf(fps * 1000.0) / 1000.0; est_frate = (int)est_fps; if( est_fps > (int)est_fps ) { est_frate = (est_frate + 1) * 1000; est_fbase = (int)roundf((float)est_frate / est_fps); } else est_fbase = 1; gcd = ff_gcd(est_frate, est_fbase); if( gcd > 1 ) { est_frate /= gcd; est_fbase /= gcd; } if( fbase > est_fbase ) { avctx->time_base.den = est_frate; avctx->time_base.num = est_fbase; av_log(avctx, AV_LOG_DEBUG, "XviD: framerate re-estimated: %.2f, %.3f%% correction\n", est_fps, (((est_fps - fps)/fps) * 100.0)); } else { avctx->time_base.den = frate; avctx->time_base.num = fbase; } }
int av_reduce(int *dst_nom, int *dst_den, int64_t nom, int64_t den, int64_t max) { AVRational a0= {0,1}, a1= {1,0}; int sign= (nom<0) ^ (den<0); int64_t gcd= ff_gcd(FFABS(nom), FFABS(den)); if(gcd) { nom = FFABS(nom)/gcd; den = FFABS(den)/gcd; } if(nom<=max && den<=max) { a1= (AVRational) { nom, den }; den=0; } while(den) { uint64_t x = nom / den; int64_t next_den= nom - den*x; int64_t a2n= x*a1.num + a0.num; int64_t a2d= x*a1.den + a0.den; if(a2n > max || a2d > max) { if(a1.num) x= (max - a0.num) / a1.num; if(a1.den) x= FFMIN(x, (max - a0.den) / a1.den); if (den*(2*x*a1.den + a0.den) > nom*a1.den) a1 = (AVRational) { x*a1.num + a0.num, x*a1.den + a0.den }; break; } a0= a1; a1= (AVRational) { a2n, a2d }; nom= den; den= next_den; } assert(ff_gcd(a1.num, a1.den) <= 1U); *dst_nom = sign ? -a1.num : a1.num; *dst_den = a1.den; return den==0; }
void ff_parse_specific_params(AVCodecContext *stream, int *au_rate, int *au_ssize, int *au_scale) { int gcd; *au_ssize= stream->block_align; if(stream->frame_size && stream->sample_rate){ *au_scale=stream->frame_size; *au_rate= stream->sample_rate; }else if(stream->codec_type == CODEC_TYPE_VIDEO){ *au_scale= stream->time_base.num; *au_rate = stream->time_base.den; }else{ *au_scale= stream->block_align ? stream->block_align*8 : 8; *au_rate = stream->bit_rate; } gcd= ff_gcd(*au_scale, *au_rate); *au_scale /= gcd; *au_rate /= gcd; }
static demuxer_t* demux_open_lavf(demuxer_t *demuxer){ AVFormatContext *avfc; AVFormatParameters ap; AVOption *opt; lavf_priv_t *priv= demuxer->priv; int i,g; char mp_filename[256]="mp:"; memset(&ap, 0, sizeof(AVFormatParameters)); stream_seek(demuxer->stream, 0); register_protocol(&mp_protocol); avfc = av_alloc_format_context(); if (correct_pts) avfc->flags |= AVFMT_FLAG_GENPTS; if (index_mode == 0) avfc->flags |= AVFMT_FLAG_IGNIDX; ap.prealloced_context = 1; if(opt_probesize) { double d = (double) opt_probesize; opt = av_set_double(avfc, "probesize", opt_probesize); if(!opt) mp_msg(MSGT_HEADER,MSGL_ERR, "demux_lavf, couldn't set option probesize to %.3f\r\n", d); } if(demuxer->stream->url) strncpy(mp_filename + 3, demuxer->stream->url, sizeof(mp_filename)-3); else strncpy(mp_filename + 3, "foobar.dummy", sizeof(mp_filename)-3); url_fopen(&priv->pb, mp_filename, URL_RDONLY); ((URLContext*)(priv->pb.opaque))->priv_data= demuxer->stream; if(av_open_input_stream(&avfc, &priv->pb, mp_filename, priv->avif, &ap)<0){ mp_msg(MSGT_HEADER,MSGL_ERR,"LAVF_header: av_open_input_stream() failed\n"); return NULL; } priv->avfc= avfc; if(av_find_stream_info(avfc) < 0){ mp_msg(MSGT_HEADER,MSGL_ERR,"LAVF_header: av_find_stream_info() failed\n"); return NULL; } if(avfc->title [0]) demux_info_add(demuxer, "name" , avfc->title ); if(avfc->author [0]) demux_info_add(demuxer, "author" , avfc->author ); if(avfc->copyright[0]) demux_info_add(demuxer, "copyright", avfc->copyright); if(avfc->comment [0]) demux_info_add(demuxer, "comments" , avfc->comment ); if(avfc->album [0]) demux_info_add(demuxer, "album" , avfc->album ); // if(avfc->year ) demux_info_add(demuxer, "year" , avfc->year ); // if(avfc->track ) demux_info_add(demuxer, "track" , avfc->track ); if(avfc->genre [0]) demux_info_add(demuxer, "genre" , avfc->genre ); for(i=0; i<avfc->nb_streams; i++){ AVStream *st= avfc->streams[i]; AVCodecContext *codec= st->codec; switch(codec->codec_type){ case CODEC_TYPE_AUDIO:{ WAVEFORMATEX *wf= calloc(sizeof(WAVEFORMATEX) + codec->extradata_size, 1); sh_audio_t* sh_audio; if(priv->audio_streams >= MAX_A_STREAMS) break; sh_audio=new_sh_audio(demuxer, i); if(!sh_audio) break; priv->astreams[priv->audio_streams] = i; priv->audio_streams++; if(!codec->codec_tag) codec->codec_tag= av_codec_get_tag(mp_wav_taglists, codec->codec_id); wf->wFormatTag= codec->codec_tag; wf->nChannels= codec->channels; wf->nSamplesPerSec= codec->sample_rate; wf->nAvgBytesPerSec= codec->bit_rate/8; wf->nBlockAlign= codec->block_align ? codec->block_align : 1; wf->wBitsPerSample= codec->bits_per_sample; wf->cbSize= codec->extradata_size; if(codec->extradata_size){ memcpy( wf + 1, codec->extradata, codec->extradata_size); } sh_audio->wf= wf; sh_audio->audio.dwSampleSize= codec->block_align; if(codec->frame_size && codec->sample_rate){ sh_audio->audio.dwScale=codec->frame_size; sh_audio->audio.dwRate= codec->sample_rate; }else{ sh_audio->audio.dwScale= codec->block_align ? codec->block_align*8 : 8; sh_audio->audio.dwRate = codec->bit_rate; } g= ff_gcd(sh_audio->audio.dwScale, sh_audio->audio.dwRate); sh_audio->audio.dwScale /= g; sh_audio->audio.dwRate /= g; // printf("sca:%d rat:%d fs:%d sr:%d ba:%d\n", sh_audio->audio.dwScale, sh_audio->audio.dwRate, codec->frame_size, codec->sample_rate, codec->block_align); sh_audio->ds= demuxer->audio; sh_audio->format= codec->codec_tag; sh_audio->channels= codec->channels; sh_audio->samplerate= codec->sample_rate; sh_audio->i_bps= codec->bit_rate/8; switch (codec->codec_id) { case CODEC_ID_PCM_S8: case CODEC_ID_PCM_U8: sh_audio->samplesize = 1; break; case CODEC_ID_PCM_S16LE: case CODEC_ID_PCM_S16BE: case CODEC_ID_PCM_U16LE: case CODEC_ID_PCM_U16BE: sh_audio->samplesize = 2; break; case CODEC_ID_PCM_ALAW: sh_audio->format = 0x6; break; case CODEC_ID_PCM_MULAW: sh_audio->format = 0x7; break; } if( mp_msg_test(MSGT_HEADER,MSGL_V) ) print_wave_header(sh_audio->wf, MSGL_V); if((audio_lang && st->language[0] && !strncmp(audio_lang, st->language, 3)) || (demuxer->audio->id == i || demuxer->audio->id == -1) ) { demuxer->audio->id = i; demuxer->audio->sh= demuxer->a_streams[i]; } else st->discard= AVDISCARD_ALL; break;} case CODEC_TYPE_VIDEO:{ sh_video_t* sh_video; BITMAPINFOHEADER *bih; if(priv->video_streams >= MAX_V_STREAMS) break; sh_video=new_sh_video(demuxer, i); if(!sh_video) break; priv->vstreams[priv->video_streams] = i; priv->video_streams++; bih=calloc(sizeof(BITMAPINFOHEADER) + codec->extradata_size,1); if(!codec->codec_tag) codec->codec_tag= av_codec_get_tag(mp_bmp_taglists, codec->codec_id); bih->biSize= sizeof(BITMAPINFOHEADER) + codec->extradata_size; bih->biWidth= codec->width; bih->biHeight= codec->height; bih->biBitCount= codec->bits_per_sample; bih->biSizeImage = bih->biWidth * bih->biHeight * bih->biBitCount/8; bih->biCompression= codec->codec_tag; sh_video->bih= bih; sh_video->disp_w= codec->width; sh_video->disp_h= codec->height; if (st->time_base.den) { /* if container has time_base, use that */ sh_video->video.dwRate= st->time_base.den; sh_video->video.dwScale= st->time_base.num; } else { sh_video->video.dwRate= codec->time_base.den; sh_video->video.dwScale= codec->time_base.num; } sh_video->fps=av_q2d(st->r_frame_rate); sh_video->frametime=1/av_q2d(st->r_frame_rate); sh_video->format = bih->biCompression; sh_video->aspect= codec->width * codec->sample_aspect_ratio.num / (float)(codec->height * codec->sample_aspect_ratio.den); sh_video->i_bps= codec->bit_rate/8; mp_msg(MSGT_DEMUX,MSGL_DBG2,"aspect= %d*%d/(%d*%d)\n", codec->width, codec->sample_aspect_ratio.num, codec->height, codec->sample_aspect_ratio.den); sh_video->ds= demuxer->video; if(codec->extradata_size) memcpy(sh_video->bih + 1, codec->extradata, codec->extradata_size); if( mp_msg_test(MSGT_HEADER,MSGL_V) ) print_video_header(sh_video->bih, MSGL_V); /* short biPlanes; int biXPelsPerMeter; int biYPelsPerMeter; int biClrUsed; int biClrImportant;*/ if(demuxer->video->id != i && demuxer->video->id != -1) st->discard= AVDISCARD_ALL; else{ demuxer->video->id = i; demuxer->video->sh= demuxer->v_streams[i]; } break;} default: st->discard= AVDISCARD_ALL; } } mp_msg(MSGT_HEADER,MSGL_V,"LAVF: %d audio and %d video streams found\n",priv->audio_streams,priv->video_streams); mp_msg(MSGT_HEADER,MSGL_V,"LAVF: build %d\n", LIBAVFORMAT_BUILD); if(!priv->audio_streams) demuxer->audio->id=-2; // nosound // else if(best_audio > 0 && demuxer->audio->id == -1) demuxer->audio->id=best_audio; if(!priv->video_streams){ if(!priv->audio_streams){ mp_msg(MSGT_HEADER,MSGL_ERR,"LAVF: no audio or video headers found - broken file?\n"); return NULL; } demuxer->video->id=-2; // audio-only } //else if (best_video > 0 && demuxer->video->id == -1) demuxer->video->id = best_video; return demuxer; }
static void handle_stream(demuxer_t *demuxer, AVFormatContext *avfc, int i) { lavf_priv_t *priv= demuxer->priv; AVStream *st= avfc->streams[i]; AVCodecContext *codec= st->codec; int g; switch(codec->codec_type){ case CODEC_TYPE_AUDIO:{ WAVEFORMATEX *wf= calloc(sizeof(WAVEFORMATEX) + codec->extradata_size, 1); sh_audio_t* sh_audio; if(priv->audio_streams >= MAX_A_STREAMS) break; sh_audio=new_sh_audio(demuxer, i); mp_msg(MSGT_DEMUX, MSGL_INFO, MSGTR_AudioID, "lavf", i); if(!sh_audio) break; priv->astreams[priv->audio_streams] = i; priv->audio_streams++; // mp4a tag is used for all mp4 files no matter what they actually contain if(codec->codec_tag == MKTAG('m', 'p', '4', 'a')) codec->codec_tag= 0; if(codec->codec_id == CODEC_ID_ADPCM_IMA_AMV) codec->codec_tag= MKTAG('A','M','V','A'); if(!codec->codec_tag) codec->codec_tag= av_codec_get_tag(mp_wav_taglists, codec->codec_id); wf->wFormatTag= codec->codec_tag; wf->nChannels= codec->channels; wf->nSamplesPerSec= codec->sample_rate; wf->nAvgBytesPerSec= codec->bit_rate/8; wf->nBlockAlign= codec->block_align ? codec->block_align : 1; wf->wBitsPerSample= codec->bits_per_sample; wf->cbSize= codec->extradata_size; if(codec->extradata_size) memcpy(wf + 1, codec->extradata, codec->extradata_size); sh_audio->wf= wf; sh_audio->audio.dwSampleSize= codec->block_align; if(codec->frame_size && codec->sample_rate){ sh_audio->audio.dwScale=codec->frame_size; sh_audio->audio.dwRate= codec->sample_rate; }else{ sh_audio->audio.dwScale= codec->block_align ? codec->block_align*8 : 8; sh_audio->audio.dwRate = codec->bit_rate; } g= ff_gcd(sh_audio->audio.dwScale, sh_audio->audio.dwRate); sh_audio->audio.dwScale /= g; sh_audio->audio.dwRate /= g; // printf("sca:%d rat:%d fs:%d sr:%d ba:%d\n", sh_audio->audio.dwScale, sh_audio->audio.dwRate, codec->frame_size, codec->sample_rate, codec->block_align); sh_audio->ds= demuxer->audio; sh_audio->format= codec->codec_tag; sh_audio->channels= codec->channels; sh_audio->samplerate= codec->sample_rate; sh_audio->i_bps= codec->bit_rate/8; switch (codec->codec_id) { case CODEC_ID_PCM_S8: case CODEC_ID_PCM_U8: sh_audio->samplesize = 1; break; case CODEC_ID_PCM_S16LE: case CODEC_ID_PCM_S16BE: case CODEC_ID_PCM_U16LE: case CODEC_ID_PCM_U16BE: sh_audio->samplesize = 2; break; case CODEC_ID_PCM_ALAW: sh_audio->format = 0x6; break; case CODEC_ID_PCM_MULAW: sh_audio->format = 0x7; break; } if(mp_msg_test(MSGT_HEADER,MSGL_V) ) print_wave_header(sh_audio->wf, MSGL_V); if((audio_lang && st->language[0] && !strncmp(audio_lang, st->language, 3)) || (demuxer->audio->id == i || demuxer->audio->id == -1)) { demuxer->audio->id = i; demuxer->audio->sh= demuxer->a_streams[i]; } else st->discard= AVDISCARD_ALL; break; } case CODEC_TYPE_VIDEO:{ sh_video_t* sh_video; BITMAPINFOHEADER *bih; if(priv->video_streams >= MAX_V_STREAMS) break; sh_video=new_sh_video(demuxer, i); mp_msg(MSGT_DEMUX, MSGL_INFO, MSGTR_VideoID, "lavf", i); if(!sh_video) break; priv->vstreams[priv->video_streams] = i; priv->video_streams++; bih=calloc(sizeof(BITMAPINFOHEADER) + codec->extradata_size,1); if(!codec->codec_tag) codec->codec_tag= av_codec_get_tag(mp_bmp_taglists, codec->codec_id); bih->biSize= sizeof(BITMAPINFOHEADER) + codec->extradata_size; bih->biWidth= codec->width; bih->biHeight= codec->height; bih->biBitCount= codec->bits_per_sample; bih->biSizeImage = bih->biWidth * bih->biHeight * bih->biBitCount/8; bih->biCompression= codec->codec_tag; sh_video->bih= bih; sh_video->disp_w= codec->width; sh_video->disp_h= codec->height; if (st->time_base.den) { /* if container has time_base, use that */ sh_video->video.dwRate= st->time_base.den; sh_video->video.dwScale= st->time_base.num; } else { sh_video->video.dwRate= codec->time_base.den; sh_video->video.dwScale= codec->time_base.num; } sh_video->fps=av_q2d(st->r_frame_rate); sh_video->frametime=1/av_q2d(st->r_frame_rate); sh_video->format=bih->biCompression; sh_video->aspect=codec->width * codec->sample_aspect_ratio.num / (float)(codec->height * codec->sample_aspect_ratio.den); sh_video->i_bps=codec->bit_rate/8; mp_msg(MSGT_DEMUX,MSGL_DBG2,"aspect= %d*%d/(%d*%d)\n", codec->width, codec->sample_aspect_ratio.num, codec->height, codec->sample_aspect_ratio.den); sh_video->ds= demuxer->video; if(codec->extradata_size) memcpy(sh_video->bih + 1, codec->extradata, codec->extradata_size); if( mp_msg_test(MSGT_HEADER,MSGL_V) ) print_video_header(sh_video->bih, MSGL_V); /* short biPlanes; int biXPelsPerMeter; int biYPelsPerMeter; int biClrUsed; int biClrImportant; */ if(demuxer->video->id != i && demuxer->video->id != -1) st->discard= AVDISCARD_ALL; else{ demuxer->video->id = i; demuxer->video->sh= demuxer->v_streams[i]; } break; } case CODEC_TYPE_SUBTITLE:{ sh_sub_t* sh_sub; if(priv->sub_streams >= MAX_S_STREAMS) break; /* only support text subtitles for now */ if(codec->codec_id != CODEC_ID_TEXT) break; sh_sub = new_sh_sub_sid(demuxer, i, priv->sub_streams); mp_msg(MSGT_DEMUX, MSGL_INFO, MSGTR_SubtitleID, "lavf", priv->sub_streams); if(!sh_sub) break; priv->sstreams[priv->sub_streams] = i; sh_sub->type = 't'; demuxer->sub->sh = demuxer->s_streams[priv->sub_streams++]; break; } default: st->discard= AVDISCARD_ALL; } }
int64_t ff_gcd(int64_t a, int64_t b) { if(b) return ff_gcd(b, a%b); else return a; }