[mythtv] Green line android patch

[Mark Spieth]

On 9/27/2018 6:06 AM, Peter Bennett wrote:
> Hi Mark
>
> I see there is a patch that was never applied, for fixing the green 
> line issue. I assigned the ticket back to you.
>
> Ticket URL: <https://code.mythtv.org/trac/ticket/13230#comment:25>
>
> I found that playback on the amazon fire stick has some ugly artifacts 
> in the display, These are fixed by reverting the ifdefs that I has 
> added that prevent use of YV12. There is a green line but it is 
> preferable to the other ugliness that I see.
>
Yes I wasnt happy with it since I had to change the ordering of the 
interleaving lines. I just recently found out that there is an option 
for that too.
The green line is all 0's for that line. I traced it down to N vs N-1 as 
the last V line (somethimes H line too). This may be nvidia specific 
which would be really annoying.
Obviously desktop seems to be working fine.
> I tried your patch in ticket 13230 but it does not seem to make any 
> difference to the green line.
>
> I suppose what I need to do is make it conditionally use NV12 based on 
> where it is running. I will try to find an appropriate way to test 
> what type of device we have.
I had NV12 working ok but the resultant picture is not nearly as good as 
YUYV as it halves the chroma lines. This also had a line count 
difference between odd/even fields and were not aligned correctly after 
deinterleaving. Looks like a herring bone type pattern after deinterleaving.

NV12 is better for low power/bus bandwidth devices as it reduces the mem 
accesses to/by the GPU. This may explain the performance difference.
>
> Let me know if you have any suggestions around this.
>
Another option somewhere in video?
32 bit?
You have probably considered these.

How about a test to the gpu with a interlaced frame (16x16 or something 
small) to check behavior. It could test for green line, deint line order 
after rendering. This is complex but only has to be done once on first 
play or startup.

Dont know.

Mark