[MPlayer-matrox] mga_vid and interlaced output via DVI (NOT tv-out)

[Michael Langguth]

> On Tuesday, September 11, 2007 1:44 AM
> "Attila Kinali" <attila at kinali.ch> wrote:
>
> Morgen!
>
>> On Sun, 9 Sep 2007 23:32:47 +0200
>> "Michael Langguth" <mail at michael-langguth.de> wrote:
>>
>> so i tried to use 576i. after i realized that the horizontal
>> resolution has to be doubled from 720 to 1440...
>
> I don't really understand what you are doing. Please
> provide at least your xorg.conf, eventually used
> mga_vid parameters and the parameters you pass to MPlayer.
> See bugreports.html for a complete list of information needed.
>

hallo attila,

i try to play a video in standard pal resolution via dvi connected to hdmi. 
as stated in my original posting, progressive modes work well in top quality. 
only interlaced modes are missing for a perfect "tv-out 2.0".

the doubled horizontal resolution is part of the hdmi spcification (see 
http://www.hdmi.org/pdf/HDMISpecInformationalVersion.pdf, capt. 6.4):

  "Video formats with native pixel rates below 25 Mpixels/sec
  require pixel-repetition in order to be carried across a TMDS
  link. 720x480i and 720x576i video format timings shall always
  be pixel-repeated."

this is the normal procedure used in any consumer device outputting 576i via 
hdmi: the device doubles each pixel and sends the signal in 1440x576i to the 
display. the display ignores every second pixel to get back the original 
720x576i. if you look in the manual of flat tv's you often will read about 
pal over hdmi as "720(1440)x576i at 50hz". higher resolutions like 1080i have 
high enough pixel rates and do not need this special treatment.


but thats not my problem. my problem is the doubling of vertical lines. i can 
reproduce this in 576i and 1080i (which has no hor. doubling), independant of 
mplayer just by using mga_vid_test. i do not use an x-server, i have a simple 
text based "gui" running in a framebuffer console.

here my fb.modes entry for the interlaced modes:

  mode "576i-50"
      # hdmi cannot handle 13.5 mhz, so every pixel has to be doubled.
      # D: 27.000 MHz, H: 31.250 kHz, V: 50.000 Hz
      geometry 1440 576 1440 576 32
      timings 37037 120 40 42 4 128 3
      laced true
  endmode

  mode "1080i-50"
      # D: 61.874 MHz, H: 28.124 kHz, V: 49.999 Hz
      geometry 1920 1080 1920 1080 32
      timings 16162 148 88 31 4 44 10
      laced true
  endmode

mplayer.conf is realative simple:

  vo=mga
  ao=alsa
  fs=yes
  framedrop=yes
  cache=8192
  monitoraspect=16:9
  aspect=16:9
  vop=hue
  contrast=-15
  brightness=10
  saturation=-15
  hue=0
  rtc=1
  mc=0.002
  autosync=100
  lirc=yes
  lircconf=/usr/local/etc/lirc/mplayer.rc
  joystick=no


insmod mga_vid is done without any parameters.


i am not sure if i was able to describe what i see on the screen: if i have a 
1080i video, only the upper half of it will be displayed, zoomed to 
fullscreen. egghead alert!

when i start mga_vid_test from the console, i see a rectangle instead of a 
square. you remember, if you run mga_vid_test, the square is displayed over 
the console. in my case this is also the case and the console remains visible 
completely in correct aspect. only the test pattern is not square but a 
rectangle with width:height = 1:2.

if it helps i can provide a photo.


by the way: is there any kind of description of the bes registers available? 
may be i could try out something by my self...


viele grüße,

michael