[FFmpeg-user] Screencast produces only gray output

Carl Eugen Hoyos cehoyos at ag.or.at
Mon Nov 19 14:48:00 CET 2012

 <look <at> ebookring.net> writes:

> Here's the original code I used that produces the 
> gray screen;
> $ ffmpeg -f alsa -ac 2 -i pulse -f x11grab -r 10 
> -s 1280x800 -i :0.0 -acodec pcm_s16le -vcodec libx264 
> -preset ultrafast -crf 0 -threads 0 output.mkv

> Output #0, matroska, to 'output.mkv':
>    Metadata:
>      encoder         : Lavf54.36.100
>      Stream #0:0: Video: h264, yuv444p, 1280x800

Can you confirm that the output file plays fine with ffplay 
(that your playback software is the culprit)?

Is the playback speed problem reproducible no matter if 
you encode with audio or without?

Carl Eugen

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