使用ffmpeg时,首先使用av_register_all()注册所有的容器格式,编解码格式,然后会用av_open_input_file打开文件。av_open_input_file的原型是 int av_open_input_file(AVFormatContext **ic_ptr, const char *filename, AVInputFormat *fmt, int buf_size, AVFormatParameters *ap) 参数ic_ptr是指向AVFormatContext指...
*/ int64_t duration; /** decoding: total file size, 0 if unknown */ int64_t file_size; /** Decoding: total stream bitrate in bit/s, 0 if not available. Never set it directly if the file_size and the duration are known as FFmpeg can compute it automatically. */ int bit_rate; ...
* needed to maintain a smaller size. This can lead to slower or less * accurate seeking (depends on demuxer). * Demuxers for which a full in-memory index is mandatory will ignore * this. * muxing : unused * demuxing: set by user */ unsigned int max_index_size; /** * Maximum amo...
data_size = av_samples_get_buffer_size(NULL, is->audio_st->codec->channels, is->audio_frame.nb_samples, is->audio_st->codec->sample_fmt, 1); memcpy(is->audio_buf, is->audio_frame.data[0], data_size);//将解码数据复制到输出缓存 } is->audio_pkt_data += coded_consumed_size;/...
* If the index exceeds this size, entries will be discarded as * needed to maintain a smaller size. This can lead to slower or less * accurate seeking (depends on demuxer). * Demuxers for which a full in-memory index is mandatory will ignore * this. * muxing : unused * demuxing: ...
* If the index exceeds this size, entries will be discarded as * needed to maintain a smaller size. This can lead to slower or less * accurate seeking (depends on demuxer). * Demuxers for which a full in-memory index is mandatory will ignore ...
// we already have one make another, bigger/smaller SDL_FreeYUVOverlay(vp->bmp); } // Allocate a place to put our YUV image on that screen vp->bmp = SDL_CreateYUVOverlay(is->video_st->codec->width, is->video_st->codec->height, SDL_YV12_OVERLAY, screen); vp->width = is->video...
--enable-small optimize for size instead of speed --disable-runtime-cpudetect disable detecting CPU capabilities at runtime (smaller binary) --enable-gray enable full grayscale support (slower color) --disable-swscale-alpha disable alpha channel support in swscale ...
Configuration options: --disable-static do not build static libraries [no] --enable-shared build shared libraries [no] --enable-small optimize for size instead of speed --disable-runtime-cpudetect disable detecting CPU capabilities at runtime (smaller binary) --enable-gray enable full grayscale...
* needed to maintain a smaller size. This can lead to slower or less* accurate seeking (depends on demuxer).* Demuxers for which a full in-memory index is mandatory will ignore* this.* muxing : unused* demuxing: set by user*/