extracting h264 raw video stream from mp4 or flv with ffmpeg generate an invalid stream

Question

I\'m trying to extract the video stream from an mp4 or flv h264 video (youtube video) using ffmpeg. The original video (test.flv) play without trouble with ffplay , ffprobe

Answer 1

To extract a raw video from an MP4 or FLV container you should specify the -bsf:v h264_mp4toannexb or -vbfs h264_mp4toannexb option.

ffmpeg -i test.flv -vcodec copy -an -bsf:v h264_mp4toannexb test.h264

The raw stream without H264 Annex B / NAL cannot be decode by player. With that option ffmpeg perform a simple "mux" of each h264 sample in a NAL unit.