[pvrusb2] Aspect ratio trouble

[Bernhard Geier]

> Try some experiments with mplayer first.  I know this is not what you
> want, but it will help to see what's happening to the stream.  Do a
> 720x576 capture into a file with the video_aspect set to 4:3.  Now do
> another capture into another file with the video aspect set to 16:9.
> Play back each with mplayer.  You should see mplayer sizing the frame
> correctly for the aspect ratio in each case.  I know this works - I've
> done it (actually I've even done this mid-stream and mplayer still  
> gets
> it right).  But if it isn't working for you here with mplayer then we
> need to investigate a problem with the driver or how you're using it.

Mplayer, Xine and MythTV show the right 4:3 or 16:9 frame, so this is  
working.

> If it *does* work, then we know that you're getting a properly  
> formatted
> stream.  So next I'd look at your playback app.  If the app isn't  
> paying
> attention to the embedded aspect ratio info, then let's hope there's a
> way to manually set that within the app - perhaps there's another  
> way to
> tell the app that your pixels aren't actually square.  What app is  
> this?
> If you can't find a way to set the desired aspect ratio from within  
> the
> app, then the only option I think you have left is to try changing the
> capture resolution so that the pixels are in fact square again.
> (Actually if the app really is assuming square pixels, then 720x576
> already isn't 4:3 - it's 5:4.)
>

The stream is technically perfect, if it's recorded in 4:3 all apps  
(and also my TV) show it in 4:3, it it's recorded in 16:9 in 16:9.
The real problem are the black borders and the image stretching.
Maybe I should not have mentioned the capure resolution but better  
that I'm living in a PAL country. As far as I know the pvrusb2 module  
does not know wide screen signalling (WSS), so I hoped to get rid of  
the black bars by setting pvrusb2 manually to 16:9.
As long as I have set  pvrusb2's aspect ratio setting  to 4:3,  
everything looks fine: No picture deformation, and black bars at the  
top and the bottom if the content is in 16:9. If I set pvrusb2 to  
16:9, the mpeg stream's aspect ratio is correctly set to 16:9, the 4:3  
picture is taken (including the black bars at top and bottom) and, by  
the 16:9 flag in the stream, simply stretched horizontaly - instead of  
just recording the middle of the picture.

Bernhard

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