avcodec_decode_video2 第三个参数 got_picture_ptr 的含义

ffmpeg 文档中这样描述 

got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.

 

ask :

(ffmpeg avcodec_decode_video) what does the value got_picture_ptr mean ,

i found it is a random num after function avcodec_decode_video() 

 

 

answer;

for almost codecs: 

*got_picture_ptr  = sizeof(AVFrame); 

It is just a flag to notice a frame ready!