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720x576 / 720x480 video output modes

Posted: Mon Aug 02, 2004 1:20 pm
by axc97c

Is it possible to get gentoox to output these modes (720x576 and 720x480) for PAL and NTSC respectivly, maintaining a 1 to 1 pixel mapping on the video encoder (no scaling).

Although this would give fairy large overscan on most TV's, its the perfect video mode for playing DVD's within gentoox.

Im looking to run these modes through a RGB scart cable.

If looked at the specs for the video encoder, and it supports output of these modes, ive just not been able to get a video output at these modes.



Posted: Tue Aug 03, 2004 1:04 pm
by axc97c
Ive got a bit firther on this. I can get both modes working almost perfectly in the framebuffer mode (with fbset). However, i cant seem to translate these modes into x-windows modes. When i use fbset -x to get the Modeline, using that i cant get anything other that a garbled display.

For 720x576 @ 50Hz, i used:

fbset -g 720 576 720 756 32 -t 36036 8 56 32 12 104 5 -extsync true -accel true
/etc/xbv/xbv DIS_FFILT 1 -auto 720 576 0 0

For 720x480 @ 60Hz, i used:

fbset -g 720 480 720 480 32 -t 37000 56 18 29 9 64 7 -extsync true -accel true
/etc/xbv/xbv DIS_FFILT 1 -NTSC -auto 720 480 0 0

Thses modes are exactly the ones i want. How can i get them working in X-Windows?

Im using the old connexant video encoder chip btw.



edit: Typo

Posted: Fri Aug 06, 2004 2:32 pm
by axc97c
Solved this.

Ive found out that 720x480 and 720x576 modes have problems within X-Windows. This seems to be a bug within the nv driver as these modes work fine in the framebuffer.

The best solution i could come up with was to use 704x480 / 704x576 modes instead which work perfectly. If anyone want the modelines for these shout up.


Posted: Mon Dec 11, 2006 10:25 pm
by chipsugar
Shouting up now. modelines would be much appreciated.

Posted: Thu Dec 14, 2006 6:28 am
by dopey
fbset can actually transalate to X modelines. That's how I got my system up and running.

Code: Select all

fbset -x

Re: 720x576 / 720x480 video output modes

Posted: Tue Feb 05, 2008 7:18 pm
by pepsi_max2k
>> If anyone want the modelines for these shout up.

4 years later... this is gonna be a hella loud shout. :o :o WWWAAAAAAANNNNNNNNNTTTT :o :o


seriously though... I've just been trying out modelines in xebian / xfree86 and came across the same bug with 720*576 modes, ie. really horizontally + diagonally stretched screen, no way of making anything out.

Strangely enough though, although the mythfrontend ui is messed up, video isn't. so what i've done now is use a 798*576 modeline for the gui and 720*576 for the vid and for the most part that works fine. will post them tomorrow but would be nice to see anyone else's pal 720 modelines and experience with setting it up on a connexant chip with xfree86.


Modeline "792x576" 29.750 792 832 912 952 576 599 601 625 -Hsync -Vsync
Modeline "720x576" 27.000 720 760 824 864 576 599 601 625 -Hsync -Vsync

replacing all "640x480" options with "792x576" to get ui to use that at boot and then use myth settings to get 720x576 enabled for video (check /var/log/XFree86.0.log to make sure it's working). they give 50Hz (and i guess progressive) output, and i'm altering overscan using this at the end of append line in linuxboot.cfg (x + y being % between 0 and 20):


it's not perfect (text is still a little blurred compared to set top box) but i don't know if the fault for that lies with the modeline or something else...