[SOLVED] Define underscan only for 720p

[p4trykx]

edit
Look for the partial solution in the last post. It's kind of workaround but it works on Sony TVs

My TV Sony KDL-46v5500 (few years old) does not support fully 720p input but works fine with 1080. The problem is that with 720p I get an overscan. Depending on video source size XBMC switches between those two resolutions.
So when I'm in the main menu or play full HD movies it displays at 1080 just fine without any overscan or black stripes at the edges.
But when displaying something less than 720p the resolution is reduced and portions of screen are cut.
The solution would be to just define somewhere the overscan just for 720p but AFAIK it's not possible to do it on config.txt without affecting 1080p.

I have another TV which works fine with both resolutions so I suspect it's a Sony bug. On LG I get (native) shown both on 720p and 1080p but on Sony only at 1080p.

From Sony

Code:

xbian@xbian:~# tvservice  -m CEA
Group CEA has 16 modes:
           mode 1: 640x480 @ 60Hz, progressive
           mode 2: 720x480 @ 60Hz, progressive
           mode 3: 720x480 @ 60Hz, progressive
           mode 4: 1280x720 @ 60Hz, progressive
           mode 5: 1920x1080 @ 60Hz, interlaced
           mode 6: 720x480 @ 60Hz, interlaced
           mode 7: 720x480 @ 60Hz, interlaced
  (native) mode 16: 1920x1080 @ 60Hz, progressive
           mode 17: 720x576 @ 50Hz, progressive
           mode 18: 720x576 @ 50Hz, progressive
           mode 19: 1280x720 @ 50Hz, progressive
           mode 20: 1920x1080 @ 50Hz, interlaced
           mode 21: 720x576 @ 50Hz, interlaced
           mode 22: 720x576 @ 50Hz, interlaced
           mode 31: 1920x1080 @ 50Hz, progressive
           mode 32: 1920x1080 @ 24Hz, progressive

From LG

Code:

xbian@xbian1:~# tvservice -m CEA
Group CEA has 15 modes:
           mode 1: 640x480 @ 60Hz, progressive
           mode 2: 720x480 @ 60Hz, progressive
           mode 3: 720x480 @ 60Hz, progressive
  (native) mode 4: 1280x720 @ 60Hz, progressive
           mode 5: 1920x1080 @ 60Hz, interlaced
  (native) mode 16: 1920x1080 @ 60Hz, progressive
           mode 17: 720x576 @ 50Hz, progressive
           mode 18: 720x576 @ 50Hz, progressive
           mode 19: 1280x720 @ 50Hz, progressive
           mode 20: 1920x1080 @ 50Hz, interlaced
           mode 21: 720x576 @ 50Hz, interlaced
           mode 31: 1920x1080 @ 50Hz, progressive
           mode 32: 1920x1080 @ 24Hz, progressive
           mode 33: 1920x1080 @ 25Hz, progressive
           mode 34: 1920x1080 @ 30Hz, progressive

[raspberry_pd]

I am experiencing the same problem with my Sony KDL - 32W5500. I haven't played around with the settings to try and fix it though. Strangely enough I also have an LG

I have the same output as you do from tvservice -m CEA and tvservice -m DMT displays:

Code:

Group DMT has 4 modes:
           mode 4: 640x480 @ 60Hz, progressive
           mode 9: 800x600 @ 60Hz, progressive
           mode 16: 1024x768 @ 60Hz, progressive
           mode 35: 1280x1024 @ 60Hz, progressive

The strange thing for me is that when I play video on the Sony and that video is not 1080p, I get a small top left on screen display from the Sony that says "720p". Or at least it has sometimes. Right now I cannot get it to do that! LOL.

I'll keep an eye on this thread to see if I can offer any help.

[p4trykx]

Maybe it would be sufficient to force only 1080p even for smaller resolutions. I think that previous version did not change the resolution.

[Bytec]

(26th Dec, 2012 10:19 PM)p4trykx Wrote:  Maybe it would be sufficient to force only 1080p even for smaller resolutions. I think that previous version did not change the resolution.

I also would like RPI to upscale all video to 1080P and skip 720P mode entirely, because my TV is not so good in upscaling.

Any advice on how to achieve all video upscaling to 1080P?

[p4trykx]

I've just checked and setting a resolution in config.txt forces xbmc to use it all the time. However it's a partial solution.

Code:

hdmi_group=1
hdmi_mode=16

[p4trykx]

Some more news. I was looking around the TV's menu and found some settings that make the screen look OK in 720p resolution.
First you have to switch to 720p in Xbian Settings System. This cuts the edges of the screen on my Sony TV. Then push Home button on remote and go to Screen Settings. I think it's the 3 active option. You can set it -1 +1 and maybe "all the pixels". In 1080p I can set it to "all the pixels" which seems to be the best but in 720p when setting "+1" the screen is about right.