[mythtv] NVidia Pixellation

David Engel david at istwok.net
Mon Jul 30 22:56:08 UTC 2018

On Mon, Jul 30, 2018 at 05:41:00PM -0400, Peter Bennett wrote:
> On 07/30/2018 04:26 PM, Aman Gupta wrote:
> > 
> >     Aman, do you have a good connection at Nvidia?  My local ABC station
> >     seems to have again started sending streams that show corruption when
> >     decoded with MediaCodec (and VDPAU, for that matter), but not when
> >     decoded with ffmpeg software.  I have a short sample that I can
> >     provide.
> > 
> > 
> > Yes I can forward the bug report and sample if you email them to me.
> > Please test the sample with the latest Exoplayer and make sure it
> > reproduces there so they can investigate easily.
> > 
> > 
> I have a channel that has this problem. The local NBC station changed hands
> at the beginning of 2017 and since then the stream gets periodic pixellation
> but only on NVidia. The pixellations are at exactly the same places on
> Shield as with VDPAU on my low-end, $20 NVidia cards. Apparently NVidia are
> using the same (faulty) software in the Shield as they have used for years
> in the low-end GEForce 210.
> These recordings play perfectly with software decoding, VAAPI, and
> *_Raspberry Pi OpenMAX_*. ($30 Raspberry Pi works better than Shield?!?).

Interestingly, when I first encountered this problem (probably 8 or
more years ago) older Nvidia cards didn't exhibit the problem.  For
example, my GT 430 and and GT 730 showed the problem, but the previous
generation 9500 GT I had my mom using didn't show it.  I reported the
problem back then and sent Nvidia several samples as requested, but it
never got fixed.

David Engel
david at istwok.net

More information about the mythtv-dev mailing list