On Thursday 09 October 2008 16:36:07 Jim Stichnoth wrote:
> I have a Hauppauge PVR-150, with the S-Video input connected to an SD
> DirecTiVo box. This is on a system running MythDora 5 -- "uname -r"
> reports 2.6.24.4-64.fc8 and "ivtvctl --version" reports "ivtvctl
> version 1.0.3 (tagged release)".
>
> I'm seeing a small problem where enabling closed captions causes the
> top 10 or so lines to be cropped and the image shifted up, leaving
> ~10 lines of black at the bottom.
>
> I took a couple of screen shots to show the problem more clearly. I
> paused the input source, then ran either "v4l2-ctl -b cc" or
> "v4l2-ctl -b off" to turn closed captioning on or off, and then
> captured a frame using xine. If you flip back and forth between the
> two images, it's clear that the first several lines are being cropped
> and everything shifted up when cc is enabled.
>
> cc on: http://www.flickr.com/photos/[EMAIL PROTECTED]/2905480460/sizes/o/
> cc off: http://www.flickr.com/photos/[EMAIL PROTECTED]/2905480878/sizes/o/
>
> I would assume that this has something to do with VBI
> removal/cleanup. But it's interesting that even with the uncropped
> picture, the VBI stuff has apparently already been removed. If I had
> to guess, I would say that VBI removal is being done twice when cc is
> on.
>
> Ideally, I would like to have the VBI "junk" preserved and rely on
> the monitor or player to handle the overscan, especially since I
> already have to deal with that for my HDHomeRun. The next best thing
> would for VBI removal (or whatever) to be done only once, yielding
> the "cc off" picture. By the way, the MythTV WAF requires closed
> captions to be preserved...
>
> Any ideas on this?
I know what this is and I guess I should pick it up again: when CC is on
the vblank register of the cx2584x is changed. In my opinion this
should not happen, but I need to verify this some more. If I recall
correctly this problem does not occur with PAL/SECAM, it is NTSC
specific.
(For those who really want to know: it's register 0x474).
Regards,
Hans
_______________________________________________
ivtv-users mailing list
[email protected]
http://ivtvdriver.org/mailman/listinfo/ivtv-users
