ffmpeg decoder warning: warning: first frame is no keyframe

[yinglcs]

I am getting this warning when I stream a flv file (source)

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ffmpeg decoder warning: warning: first frame is no keyframe

My full command:

Code: Select all

vlc -vvv -I dummy video.flv --sout '#transcode{vcodec=mp4v,vb=400,acodec=mpga,ab=128}:rtp{dst=127.0.0.1,port-video=3342,port-audio=3346,sdp=file:///usr/local/movies/test.sdp}'

However, when I just use vlc to view the same flv file, I don't see the same ' first frame is no keyframe' warning.

Can you please tell me why? I assume using vlc to view a flv and using vlc to stream a flv are using the same flv deocder.
Then why it can find the keyframe when viewing not but when streaming?

I am investing why vlc has a lot of green areas in the beginning of streaming flv file. I wonder if this has anything to do with it.

Thank you.