I FOUND OUT SOLUTION
For all GNOME users who use nautilus but no thumbnail for .flv files.
I had installed ffmpegthumbnailer (version:1.3.0-1) using
#apt-get install ffmpegthumbnailer
For flv video.Run
Edit string of /desktop/gnome/thumbnailers/video@x-flv/command to
"/usr/bin/ffmpegthumbnailer -s %s -i %i -o %o -f -t 25"(without double quotes).
I have noticed that avi files are supported by gnome-video-thumbnailer so ffmpegthumbnailer was not used in ubuntu 9.04 64bit edition no matter whatever I try.
i reached the developer who replied(so nice of him
) to use ffmpegthumbnailer 1.5.6 on ubuntu 9.10 and consult http://code.google.com/p/ffmpegthumbnailer/wiki/Faq
NOTE:string I have mentioned above is slightly different(but worked well) than mentioned on wiki.
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