MythTV TV-Out Mode Error

[quixote23]

I'm having trouble getting my MythTV box to display properly on my TV. I am getting an image, but there's no colour and the picture is distorted and seems to be at a resolution too large for the TV. I've messed around with xorg.conf endlessly but nothing I add or change seems to make any difference. I'm a linux noob and I just installed MythBuntu a couple of days ago so it's possible there's something really obvious that I'm missing. Any help would be appreciated.

Video card: ATI Radeon 9550
Driver: fglrx
Connection: S-Video

xorg.conf below:


# xorg.conf (X.Org X Window System server configuration file)
#
# This file was generated by dexconf, the Debian X Configuration tool, using
# values from the debconf database.
#
# Edit this file with caution, and see the xorg.conf manual page.
# (Type "man xorg.conf" at the shell prompt.)
#
# This file is automatically updated on xserver-xorg package upgrades *only*
# if it has not been modified since the last upgrade of the xserver-xorg
# package.
#
# If you have edited this file but would like it to be automatically updated
# again, run the following command:
# sudo dpkg-reconfigure -phigh xserver-xorg

Section "ServerLayout"
Identifier "Default Layout"
Screen 0 "aticonfig-Screen[0]-0" 0 0
EndSection

Section "Files"
EndSection

Section "Module"
EndSection

Section "InputDevice"
Identifier "Generic Keyboard"
Driver "kbd"
Option "XkbRules" "xorg"
Option "XkbModel" "pc105"
Option "XkbLayout" "us"
EndSection

Section "InputDevice"
Identifier "Configured Mouse"
Driver "mouse"
Option "CorePointer"
EndSection

Section "Monitor"
Identifier "aticonfig-Monitor[0]-0"
ModeLine "640x480" 25.2 640 656 720 840 480 481 484 500 -hsync -vsync
HorizSync 15-45 # 31.47 # 60
VertRefresh 50-60 # 59.94 # 56-76
Option "VendorName" "ATI Proprietary Driver"
Option "ModelName" "Generic Autodetecting Monitor"
Option "DPMS" "true"
EndSection

Section "Device"
Identifier "aticonfig-Device[0]-0"
Driver "fglrx"
Option "ForceMonitors" "tv,none"
Option "NoTV" "no"
Option "TVOutFormat" "S-VIDEO"
Option "VideoOverlay" "off"
Option "OpenGLOverlay" "on"
Option "TVFormat" "NTSC"
Option "UseInternalAGPGART" "no"
Option "XAANoOffscreenPixmaps" "on"
Option "TexturedVideo" "on"
Option "Textured2D" "on"
Option "TexturedXrender" "on"
Option "UseFastTLS" "1"
BusID "PCI:1:0:0"
EndSection

Section "Screen"
Identifier "aticonfig-Screen[0]-0"
Device "aticonfig-Device[0]-0"
Monitor "aticonfig-Monitor[0]-0"
DefaultDepth 24
SubSection "Display"
Viewport 0 0
Depth 24
Modes "640x480" "832x624" "300x200" "800x600"
EndSubSection
EndSection

[SiHa]

My first thought is 'ATI, that's the problem'. In common with many others I found ATI to be unuseable for video.

I have a couple of thoughts:

I *think* the correct value for TVOutFormat is "SVIDEO" (no '-').

How many pins does the S-Video connector on your card have. I aquired a PNY Nvidia FX7200, which had a VIVO (video in-video out) port on the back with 9 pins. PNY customer support said I could use a standard 4-pin S-Video lead, but it didn't work - I got B&W. If you've got more than 4 and you're using a standard cable, that might be your problem.

When you say the resolution is too large - how much? If you're missing an inch or so around the edges that's just the TV overscan. I'm not sure about ATI, but with the Nvidia utils, there's a slider to correct overscan for TV-Out.

In MythTV there's a screen setup wizard that will allow you to adjust the size of of the GUI to within the visible portion of your screen. Beware that if you're using Mythbuntu (the xfce desktop), you might need to hide the panel at the top of the screen - there's a known bug that causes the MythTV GUI to appear below this panel if it's anything other than full-screen

[quixote23]

Okay, I finally got it to work after going back to my initial backed-up xorg.conf and running aticonfig and messing with the options. My only problem now is slightly diagonal scanlines running across the screen. I suspect these may be coming from one of three sources:

1. My refresh rate isn't configured properly. The TV is 60.0hz NTSC-M and that's what I have it set to in xorg.conf.

2. Interlacing. I haven't really figured out modelines and that seems to be the only way to change interlacing settings.

3. Poorly-shielded and\or cheap cables. I'm using a 4-pin S-Video cable that seems to work fine on other devices (DVD player, etc) so I'm not really sure if this is likely.

Any ideas?