Understanding of media codecs and containers. This type of content is only available toįfmpeg copy encoder and bitstream filters and requires a fairly good Copy content, that is encoded content stored asįfmpeg internal packets.It can be used to avoid data copies back and This type of content is only available to ffmpegįilters and raw encoders. Raw content, that is decoded content but stored asįfmpeg internal frame.Liquidsoap operators: PCM audio and YUV420p

Internal content, that is content available to all.3.Since the 2.0.x release cycle, liquidsoap integrates aįfmpeg support includes 3 types of content: LOGCATE( 'DecoderBase::InitFFDecoder avformat_open_input fail.') Open the input file and unpack it if(avformat_open_input(m_AVFormatContext, m_Url, NULL. M_AVFormatContext = avformat_alloc_context() AVFrame: Stores audio or video decoded data (raw data).AVPacket: Stores audio or video encoded data.AVStream: a structure for storing audio or video streaming information.AVCodec: a structure for storing codec information.AVCodecContext: a structure that must be used for encoding and decoding, including the type of the codec, the width and height of the video, the number of audio channels, and the sampling rate.AVFormatContext: a structure for unsealing functions, including file name, audio and video stream, duration, bit rate, etc.Lei xiaohua's audio and video processing flow chart, we have roughly understood the processing flow of this section :(Mp4 files) unpacking protocol - unpacking - video decoding - scaling or format conversion - rendering.

This paper will use FFmpeg to decode the video stream of an Mp4 file, then use libswScale to convert the decoded YUV frame into RGBA frame, and finally use ANativeWindow to render. The original article was first published on the wechat official account Byteflow

Ffmpeg decoder