[pvrusb2] aspect ratio

[Mark Brand]

Here's a speculative question about the possibility of automatic
detection of aspect ratio.

While using mplayer or xine to play /dev/video, the aspect ratio of the
displayed video is automatically adjusted on the fly when one changes
ctl_video_aspect between 4x3 and 16x9. I suppose mythtv does this too,
but I have not tried. Anyway, my conclusion is that ctl_video_aspect
sets the aspect ratio flag embedded in the MPEG-2 stream coming out of
the pvrusb2.

It seems to me that it would be nice if the pvrusb2 device could
automatically detect the aspect ratio of the incoming signal (whether
broadcast, composite or s-video) and set the flag accordingly. At
present, I have to visually decide what the intended aspect ratio is and
manually set ctl_video_aspect, which is inconvenient. I am particularly
interested in having this functionality for composite and s-video.
(Analog TV broadcasts have stopped here). But, I have to admit that I
don't even know if composite or s-video contains information about
aspect ratio. Would someone care to comment?

Mark