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

[Mike Isely]

On Tue, 11 Jan 2005, Mike Isely wrote:

>
> On Tue, 11 Jan 2005, El Draper wrote:
>
>    [...]
>
> >
> > Mike:
> > Sorry, I should have said I am using version 0.16 of MythTV, but in RPM
> > format from atrpms.net. I have tried setting the size to 352x240 (as you
> > may have seen from the log output previously it was set to 480x480)
> > however this hasn't solved the problem:
> >
> > 2005-01-11 15:50:19 TuneToFrequency(11636)
> > 2005-01-11 15:50:19 Changing from None to RecordingOnly
> > 2005-01-11 15:50:19 Using profile 'Default' to record
> > 2005-01-11 15:50:19 Commercial Detection initialized: width = 352,
> > height = 240, fps = 25, method = 1
> > NVR: v4l2: format set, getting yuyv from v4l, converting
> >
> > [1]+  Segmentation fault      mythbackend -v all
> >
> > Just so I'm sure, I changed the width and height in the "codecparams"
> > table of the mythtv database, for the profiles that I'm using (in this
> > case, "Default"). Are there any other width/height capture sizes that
> > have any effect here, that maybe are still set to something bigger and
> > are causing a problem?
>
>    [...]
>
> El:
>
> The only things I can think of are:  (1) If you just tested this change
> with LiveTV (but I note from your original message that you tested
> recording) then you also need to change the LiveTV profile's encoding size
> to 352x240.  (2) I encountered this problem with a CVS snapshot (from
> 9-Jan-2005), so we're not running the same codebase.  Perhaps there is
> another problem in 0.16 since solved...
>
> I plan tonight on chasing my problem further; when/if I figure it out the
> rest of the way perhaps that might shed more light on this.
>
>   -Mike
>

El:

I looked at my situation further and found the cause.  I had been trying
to do 720x480 with this cx88 capture driver, and it just doesn't appear to
handle it well.  The segmentation fault is because mythbackend is running
off the end of the buffer given to it by the driver - because the driver
didn't provide a big enough buffer.  Trying 480x480 works fine for me, and
that's what you were using.  My situation strictly isn't a mythtv problem
(though any program which handles being fed garbage by throwing up likely
needs some fixes of its own).

Sorry I couldn't provide any useful help.

  -Mike


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