[mythtv-users] MythTV/CX88 Problems (yuyv)

[Mike Isely]

Which version of mythtv is this?  CVS?  0.16?

I just hit what may be the same problem in setting up an ATI TV Wonder
last night - also cx88xx based.  The yuyv conversion is a piece of logic
that changes the frame buffer format on the fly.  It's definitely there,
but it also stack allocates a large buffer to do the conversion and from
looking at the source I suspect the buffer may be too small for the
incoming frame buffer size.  I'm not entirely sure of the specifics yet,
but I did note that the "default" size was 352x240 and when I changed the
software encoder's setting to 352x240 the segmentation fault went away and
Live TV started working.  Try changing that and see if it helps.

This is the bug I just wrote up about the problem:

http://www.mythtv.org/bugs/show_bug.cgi?id=189

By the way, if/when you do get LiveTV working, are the colors trashed and
the picture washed out?  That's a second problem I noticed.  It appears
that the contrast has to be backed off to around 35%, and the Hue setting
seems to have been implemented to think that the Hue V4L2 parameter is an
unsigned char when in fact it's behaving like a signed char.  Setting Hue
to 0 or 100% will fix the colors.  (Set the _recording_ Hue, not the
playback Hue.)

  -Mike


On Tue, 11 Jan 2005, El Draper wrote:

> Hi guys,
> I've been setting up a Linux PVR using MythTV on a Fedora Core 3
> machine, with a recompiled 2.6.9 kernel (to fix some wifi issues). I
> have a Hauppauge WinTV PCI tv card (CX88) and have successfully got the
> program Zapping working with it, and capturing video etc. I have
> configured MythTV, grabbed program listings etc, setup some channels;
> however whenever the backend starts to record something I've setup to be
> recorded, I get the following error:
>
> 2005-01-11 02:39:17 Changing from None to RecordingOnly
> 2005-01-11 02:39:17 Using profile 'Default' to record
> 2005-01-11 02:39:17 Commercial Detection initialized: width = 480,
> height = 480, fps = 25, method = 1
> NVR: v4l2: format set, getting yuyv from v4l, converting
>
> [2]+  Segmentation fault      mythbackend -v all
>
> Now (from what little I know) yuyv is some form of codec? Could it be
> that Myth has a missing dependency for this on my machine that is
> causing this error? I have noticed that in trying to setup my channels
> with the correct frequencies, I don't see anywhere for the exact
> frequency in Mhz ("finetune" and "freqid" are int's). How can I setup a
> channel with an exact frequency in Mhz? Could this be causing the above
> problem when trying to record?
>
> I've searched around, so far unsuccessfully on this problem, so any help
> you guys can offer would be great as I'm now a little stuck :-)
>
> Thanks!
>
> -= El =-
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>
>

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