[mythtv-users] Corrupted bottom line of pixels (THAT IS ABSOLUTELY DEFINITELY NOT IN THE SOURCE!!!!)

Paul Gardiner lists at glidos.net
Wed Sep 1 08:39:13 UTC 2010


On 01/09/2010 05:33, Glen Hawksworth wrote:
>
>
> On Tue, 2010-08-24 at 09:28 -0400, Michael Lynch wrote:
>> On Tue, Aug 24, 2010 at 9:23 AM, David Asher<asherml at gmail.com>  wrote:
>>> Its certainly seeming likely.
>>>
>>> My case is #3, but it is also associated with the HD-PVR.  I only see the issue with HD-PVR 1080i recordings.  I switched the STB to output only 720p and have had no issues (which is why this dropped pretty low on my todo list).  My OTA MPEG-2 1080i recordings have had no issues.
>>>
>>> David.
>>>
>>
>> Same here, green line on the bottom with HD-PVR at 1080i, swapping to
>> 720p removes the line, but then causes the Dish Network audio/video
>> lag problems.  That said, I'm just living with the green line and
>> hoping one of these firmware updates will fix it.
>
> 2 cents:
>
> I don't know if it helps but I get a dotted line on the bottom edge of
> some of my DVB channels and all I do is overscan the picture 1% and it
> is kicked off the bottom.

Interesting. Is that on an ION board? Do you see a four-fold repeating
pattern? Is it a single line of your display, or a single line of the
source?

Yeah, I can set overscan on my TV to get rid of it, but I don't like
doing that for two reasons. The main reason, is that I have conclusive
proof that the corruption is not in the source. So it is definitely a
fault in either MythTv, a driver, or the hardware. Absolute certainty
because:

1) I can change the scaling and offset in myth, so that what would be
the effected area of the source is miles off screen, but still the
last screen line shows the same type of corruption.

2) I sometimes see the corrupted line in MythMusic visualisations.

3) Viewing the source on other players shows no corrupted line.

The other reason I don't like using overscan is that it means there
will be two phases of scaling applied to the picture that cannot
help but slightly reduce quality (although on SD that might be
indiscernible). My TV - when not overscanning - gives 1-1 pixel
mapping.

Cheers,
	Paul.


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