I have a 1080p wmv video that I'd like to convert to a lower quality (preferably 720p) video. I would like to keep the audio intact. How can I accomplish this in Ubuntu?


Since you used an ffmpeg tag I will use that for the answer.

ffmpeg -i input.wmv -s hd720 -c:v libx264 -crf 23 -c:a aac -strict -2 output.mp4

Change the video quality by specifying a different CRF parameter. See the x264 encoding guide for more info.

  • 1
    Option 'sameq' was removed. If you are looking for an option to preserve the quality (which is not what -sameq was for), use -qscale 0 or an equivalent quality factor option. – juanmah Apr 4 '13 at 9:15
  • According to ffmpeg's wiki, this can be as simple as: ffmpeg -i input.avi -vf scale=-1:720 output.avi – andersonvom Feb 9 '17 at 17:35

Time has moved on a little since the original accepted answer for this question in 2012. Newer versions of FFmpeg would be better to use FFmpeg's 'scale' video filter.

I give an example below, using this filter, which also simply copies the audio track as you have requested:

ffmpeg -i input.wmv \
       -c:v libx264 -preset veryslow -tune film -crf 22 -vf scale=-2:720 \
       -c:a copy \

The -tune film option given above can be omitted or you could try -tune animation depending on the type of video clip you are using.

If you decided that you would like to transcode the audio a good choice would be to use the external library libfdk_aac as follows:

ffmpeg -i input.wmv \
       -c:v libx264 -preset veryslow -tune film -crf 22 -vf scale=-2:720 \
       -c:a libfdk_aac -b:a 128k \

This is certainly what I would do with a wmv file that I was scaling, you will find the results more than acceptable...


If you want to keep intact all the audio tracks, subtitles and so on, you should use something like this:

ffmpeg -i input.mkv \
       -map 0:0 -map 0:1 -map 0:2 -map 0:3 -map 0:4 \
       -vf scale=-1:720 -c:v libx264 -crf 18 -preset veryslow \
       -c:a:0 copy -c:a:1 copy -c:s copy \

In this case, the input.mkv file has two audio tracks and two subtitles. You can specify all the audio tracks (or subtitles, or videos, etc.) one by one or as a single entity (as I specified for subtitles).

Hope it helps...

  • 1
    You don't need to specify each stream in the manner above: -map 0:0 -map 0:1 -map 0:2 -map 0:3 -map 0:4 Instead, you can simply specify -map 0 instead. This will automatically select all streams in input 0. similar with audio copy codecs. The only codec options you need to specify are -c:copy -c:v libx264. This means: "set all stream codecs to copy, except video which should transcode to x264." – Cheekysoft May 26 '16 at 14:59
  • Equivalent (showing parameter ordering): ffmpeg -i input.mkv -map 0 -vf scale=-1:720 -c:copy -c:v libx264 -crf 18 -preset veryslow output.mkv – Cheekysoft May 26 '16 at 15:07

protected by Community Oct 13 '16 at 3:21

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