[FFmpeg-user] Slow conversion when using very low frame rates

[Tobias Rapp]

Hi,

I'm making some kind of "video preview" files from 25Hz SD/HD AVI files by
scaling the frames and lowering the frame rate. During the process I
noticed that when I use a command like:

$ ffmpeg -i ffmpeg-huffyuv.avi -codec:v mjpeg -r 1:5 -an -y ffmpeg-test.avi

the processing needs still around 80% of the original processing time even
though only about 1% of the frames are passed through. It seems like FFmpeg
is still reading and decompressing each image before dropping 99% of the
frames.

Is there another option to reduce frame-rate in a more optimized manner?

Regards,
Tobias