NVIDIA Component Out
These are the tricks for me in order to get component out to work with a Nvidia card on a MythTv box. Note that doing component out directly from a graphics cards is far from an ideal setup for high definition. Using a television that supports DVI is the best method. Utilizing a VGA to component transcoder provides higher quality. For anyone that does not have a TV capable of DVI or VGA and wanting to avoid the expense of a transcoder, this is one option that works.
I have included a summary of inforation from the MythTV users list and nvnews.com forums. You can look there for more detailed answers. Please edit this page if you find more accurate information and can provide clarification.
This guide assumes a person has the Nvidia drivers loaded and functioning for VGA.
The Nvidia Linux drivers have "TVStandard" and "Modes" that supports component out directly from the card. No modelines required! To get it going, look at the following Xorg.conf. The key line to getting the component out to work is TVStandard. Note: Component is not a valid "TVStandard" such as SVideo and component. The NVidia README is a great resource for those looking to better understand the options.
Section "Screen" Identifier "Default Screen" Device "NVIDIA Corporation NV43 [GeForce 6600]" Monitor "Visual Sensa" DefaultDepth 24 Option "TVStandard" "HD1080i" SubSection "Display" Depth 24 Modes "1920x1080" EndSubSection End Section
Section "Monitor" Identifier "Visual Sensa" HorizSync 15.0 - 620.0 VertRefresh 15.0 - 600.0 Option "DPMS" Option "ConnectedMonitor" "TV" EndSection
There's a bug in Nvidia: If you try to do video at 1080i, X will lock up. This is a bug on all Nvidia versions up through and including, 8756. To workaround that, launch nvidia settings. Make sure that 'Sync to VBlank' under Video Texture Adaptor is NOT checked. Also, in Xorg.conf, include the line, Option "RenderAccel" "True" as you can see in my Xorg above. Finally, the nvidia-settings need to be loaded everytime X starts. I have a line in my startup group that runs the command: nvidia-settings -l I think there is a cleaner way to do this with a line in your xorg but I don't know how to do that. Please edit this WIKI if you know what that line is.
I haven't tested the "Option "ConnectMonitor" "TV" I added that last minute after realizing the component out wouldn't work unless I disconnected my monitor and connected the television directly. I know that connecting the component through an A/V reciever without that line is a bad idea. Unless the card detects a television is connected directly to it, the card won't enable the TV-Out encoder.
That's it. Component out from Mythtv without a transcoder.
1). Overscan. There is no way to compensate for the televisions overscan since the TVStandard "HD1080i" overrides all modelines from what I can tell and there is no overscan setting in nvidia-settings when 1080i is selected. A workaround to this problem is to set the gui size in the MythTV general settings. I had to cut more than 100 pixals out of my picture for both height and width which makes me believe it is a nvdia problem (or my problem) more so than the TV. Then check play video at the size of gui. Others have complained about artifacts in the screen but I don't see anything so this works for me.
2). Interlacing. I have interlacing artifacts. They are minor, only a line or two at the top of the screen during scenes with significant motion but it is annoying none the less.
3). The bug. The bug in Nvidia is not likely to get fixed. There aren't currently many people that have this setup so Nvidia doesn't have the bug high on their development list. I got that from their Nvidia Linux forum.
A big warning: The quality coming from the component out is not nearly as good as other options. Here is a post if you are considering buying a 6200 for component out capability. http://www.nvnews.net/vbulletin/showthread.php?t=67261&highlight=6200+component