Transcode to change aspect ratio from 4:3 to 16:9
Posted: 03 Aug 2013 00:07
Hi. Can anyone help me with this aspect ratio conversion problem? I have a recording which is in the wrong aspect ratio. It's 720x576 and should be displayed in widescreen 16:9. Due to some mix-up at the encoding stage it is wrongly identified as 4:3. So when I play it in VLC it appears squashed by default. In the player I can manually change the aspect ratio to 16:9 and everything looks fine.
But I need to fix the source file permanently. In theory it should be possible to do it without transcoding. All the bits in the picture can stay exactly as they are. I assume it's just some labelling in the headers that needs to change so the picture is displayed correctly. I tried various ways to do this and failed completely.
So now I'm resigned to transcoding the entire video stream. But I still can't find a way to do it in VLC. I tried using a command like this.
It looks like the --aspect-ratio option is being ignored. Maybe this only applies to the on-screen player. Is there Is there a way to do this conversion with VLC?
But I need to fix the source file permanently. In theory it should be possible to do it without transcoding. All the bits in the picture can stay exactly as they are. I assume it's just some labelling in the headers that needs to change so the picture is displayed correctly. I tried various ways to do this and failed completely.
So now I'm resigned to transcoding the entire video stream. But I still can't find a way to do it in VLC. I tried using a command like this.
Code: Select all
vlc myfile.mpg --aspect-ratio="16:9" :sout=#transcode{vcodec=mp2v,vb=4096,fps=25,height=576,width=720}:file{mux=ps,dst=vid020.mpg}