user7956: I have a video (.mpg) and currently it has the wrong aspect ratio (16:9).  I now want to change it to the correct aspect ratio (5:4).  How can I do this?
I know that on VLC player I can change the aspect ratio while the video is playing.  However, I am wondering if there is a permanent way of changing the aspect ratio, such that each time this video is played, it is in the correct aspect ratio?
Thank you.

user8075: It's easy to do this with FFmpeg which is run from the command line.
Method 1 – this will size the video appropriately and encode the result in H.264 MP4 format:
ffmpeg.exe -i inputfile.mpg -vcodec h264 -s 720x576 -aspect 5:4 outputfile.mp4

Method 2 – this will set a hint in the file as to the size it should be displayed at (with no recompressing or quality loss). VLC should respect this although not all players/editors will:
ffmpeg.exe -i inputfile.mpg -vcodec copy -aspect 5:4 -acodec copy outputfile.mpg

Method 3 – if you detect a decrease in the quality of the MPEG you can compress it at a high-bitrate MPEG-2:
ffmpeg.exe -i inputfile.mpg -vcodec mpeg2video -aspect 5:4 -acodec pcm_s16le -b 30000k outputfile.mpg

Good luck!

7956: <p>I have a video (.mpg) and currently it has the wrong aspect ratio (16:9).  I now want to change it to the correct aspect ratio (5:4).  How can I do this?</p>

<p>I know that on VLC player I can change the aspect ratio while the video is playing.  However, I am wondering if there is a permanent way of changing the aspect ratio, such that each time this video is played, it is in the correct aspect ratio?</p>

<p>Thank you.</p>
 8075: <p>It's easy to do this with FFmpeg which is run from the command line.</p>

<p><strong>Method 1</strong> – this will size the video appropriately and encode the result in H.264 MP4 format:</p>

<pre><code>ffmpeg.exe -i inputfile.mpg -vcodec h264 -s 720x576 -aspect 5:4 outputfile.mp4
</code></pre>

<p><strong>Method 2</strong> – this will set a hint in the file as to the size it should be displayed at (with no recompressing or quality loss). VLC should respect this although not all players/editors will:</p>

<pre><code>ffmpeg.exe -i inputfile.mpg -vcodec copy -aspect 5:4 -acodec copy outputfile.mpg
</code></pre>

<p><strong>Method 3</strong> – if you detect a decrease in the quality of the MPEG you can compress it at a high-bitrate MPEG-2:</p>

<pre><code>ffmpeg.exe -i inputfile.mpg -vcodec mpeg2video -aspect 5:4 -acodec pcm_s16le -b 30000k outputfile.mpg
</code></pre>

<p>Good luck!</p>
