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 gives an error as follow:
ffprobe version N-55515-gbbbd959 Copyright (c) 2007-2013 the FFmpeg developers
built on Aug 13 2013 18:06:32 with gcc 4.7.3 (GCC)
configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-av
isynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enab
le-iconv --enable-libass --enable-libbluray --enable-libcaca --enable-libfreetyp
e --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --ena
ble-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-l
ibopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libsp
eex --enable-libtheora --enable-libtwolame --enable-libvo-aacenc --enable-libvo-
amrwbenc --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --
enable-libxvid --enable-zlib
libavutil 52. 42.100 / 52. 42.100
libavcodec 55. 27.100 / 55. 27.100
libavformat 55. 13.102 / 55. 13.102
libavdevice 55. 3.100 / 55. 3.100
libavfilter 3. 82.100 / 3. 82.100
libswscale 2. 4.100 / 2. 4.100
libswresample 0. 17.103 / 0. 17.103
libpostproc 52. 3.100 / 52. 3.100
[flv @ 000000000031ea80] Stream discovered after head already parsed
Input #0, flv, from 'test.flv':
Metadata:
starttime : 0
totalduration : 142
totaldatarate : 692
bytelength : 12286492
canseekontime : true
sourcedata : B42B95507HH1381414522145462
purl :
pmsg :
Duration: 00:02:22.02, start: 0.000000, bitrate: 692 kb/s
Stream #0:0: Video: h264 (Main), yuv420p, 640x268, 568 kb/s, 23.98 tbr, 1k t
bn, 47.95 tbc
Stream #0:1: Audio: aac, 44100 Hz, stereo, fltp, 131 kb/s
Stream #0:2: Data: none
Unsupported codec with id 0 for input stream 2
to get rid of the extra streams ( I only needs the video) I used the following ffmpeg command line:
ffmpeg -i test.flv -map 0:0 -vcodec copy -an -f h264 test.h264
The new stream is unreadable by any player including ffplay and gives an error with ffprobe : test.h264: Invalid data found when processing inputq= 0B f=0/0
Any body have an idea about what am I doing wrong?
I also tried simpler youtube command line:
ffmpeg -i test.flv -vcodec copy -an test.h264
if I use another format (avi for example):
ffmpeg -i test.flv -vcodec copy -an test.avi
the output video is valid.
If I transcode the video
ffmpeg -i test.flv -an test.h264
the output is also valid
Any suggestions?
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.
来源：https://stackoverflow.com/questions/19300350/extracting-h264-raw-video-stream-from-mp4-or-flv-with-ffmpeg-generate-an-invalid