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I'm using ffmpeg to generate image previews from flv videos. The OS is Debian 5 and it's the apt version of ffmpeg. The flv files are located on a NAS share that is mounted as NFS. Getting the thumbnails from the beggining of the flvs is pretty fast but is very slow when seeking above 10 minutes into the video. I call ffmpeg from python like so:

os.system('ffmpeg -ss "%d"  -i %s -an  -r 1 -vframes 1   -bufsize 1835k -s 360x288 -f image2 -vcodec mjpeg -y "%s"'%(offset_seconds, video_file_path,  image_path))

Is there a way to speed the seeking process towards the end of the flvs? What could cause it to be so slow?

I've tried the same thing on my local machine (Mac OS X snow leopard with ffmpeg compiled from source) and I can't feel any difference in speed when capturing images from the begging of the video and 50 minutes into the video.

Edit: The mentioned debian server has a faster hardware configuration than my local machine.

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migrated from Jun 22 '11 at 9:56

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