You've got a 720p video, that contains a picture that's only 4:3, so the edges left and right stay empty/black. And you want to cut off the left and right so that video is 4:3
- Input: WMV, 1280x720px - Output: WMV, AVI or MPEG, 960x720px
With a recent version of ffmpeg, you can achieve this effect from the command-line:
ffmpeg -i input.mp4 -filter:v 'crop=ih/3*4:ih' \ -c:v libx264 -crf 23 -preset verfast -c:a copy output.mp4
The -crf 23 -preset veryfast are libx264 options that set the quality. Basically: a lower CRF=better quality, but larger file. A faster preset means faster encoding, but a larger file. See this page on the excellent FFmpeg wiki for details of their use - superuser.com
See the ffmpeg filter documentation for more information about the crop filter.
# See also