Some test or trimed codes from ffmpeg, based on version 4.1. The demo programs are all compiled & tested under MSYS2 and RaspberryPi.
use another API(avformat_open_input) replace some codes, and save decoded audio data(PCM) to wave file(RIFF Wave format).
A trimed program from ffplay, codes for video removed.
Another trimed program from ffplay, codes for video removed.