On Fri, 28 Jan 2011 09:57:50 +0000 (GMT)
Stuart Morris <stuart_mor...@talk21.com> wrote:

> Standard definition video is going to be harder than I thought.
> I used xrandr to set this mode via HDMI to my LCD TV:
> # 1440x576i @ 50Hz (EIA/CEA-861B)
> ModeLine "1440x576" 27.000 1440 1464 1590 1728 576 581 587 625 -hsync
> -vsync Interlace The TV reported mode 576i ok, but the desktop
> graphics were unreadable. I tried to view an interlaced standard def
> video using my little test application and it looked awful. However
> the 1080i mode worked very well: # 1920x1080i @ 50Hz (EIA/CEA-861B)
> Modeline "1920x1080" 74.250 1920 2448 2492 2640 1080 1085 1095 1125
> +hsync +vsync Interlace
> 
> I think for standard definition video via HDMI there will be a need to
> upscale to a resolution better supported by HDMI and that requires
> inverse telecine and deinterlacing. This may still be within the
> capabilities of todays low power systems.
> 
> My little test has staisfied me that 1080i or 1080p video can be
> displayed with interlaced output.
> 
> Stuart
> 
> BTW my hardware setup was an old Sony KDL32V2000, and AMD HD4200
> integrated graphics with the AMD closed driver.

I have the same model of TV (I still think of mine as quite new!). For
SD I just use 1280x720 progressive. The PC can deinterlace and upscale
576i with negligible CPU/GPU. I have to say xine's software rendering
doesn't give as good a picture as the TV's DVB-T, but I thought
subjectively upscaling to 720p looked better than using a native 576
line mode. I haven't had much success with libxine and VDPAU so far, but
I haven't tried since updating my NVidia drivers etc to Debian
"experimental" (260.19.21). The "unstable" ones are quite out of date
(195.36.31) because of the impending Debian release. I've had VDPAU
working OK in mplayer for ages though.

The TV's 1280x720 modes are better for video than the 1360x768 native
resolution because it automatically turns on some processing and colour
balance features, but the overscan and scaling make it unsuitable for
the desktop.

Another feature of this TV is that 1280x720 forces 16:9, but 720x576
enables the various options for 4:3 (centre, zoom, "smart", 14:9) so you
could use mode switching as a form of aspect ratio signalling. However,
changing mode causes the picture and sound to blank out for several
seconds :-(.

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