Myself and other users have complained about jitter, bouncing up and down, whatever in the you want to call it in the GUI when you switch to 1080i output on a nvidia card with the 6629 drivers. Newer drivers break 1080i altogether. Playback seems fine but the GUI gives you a headache to look at.

After fiddling around over the course of a few weeks I have finally managed to come up with a setup I can work with and thought I would share.

First I use this modeline which I picked out of PowerStrip which should be standard 1080i output.



Then I choose a Display Size that gave me the biggest GUI font the buttons for the blue skin could handle. By upping the Display Size option in the XFconfig-4 "Monitor Section", I kept increasing the hsize by multiples of 16 and the Vsize by multiples of 9



I then changes the GUI size and pixel offsets under the Setup-> appearances menu. I basically inched over and down until I could see desktop and then backed off a few pixels. Then I decreased the GUI size until I could see some desktop on the bottom and right and then added a few more pixels.
Be sure to uncheck the box that says something like use GUI size for TV playback. (maybe not depending on how much overscan you get.)

Then I changed all the font sizes to the biggest size that wouldn't screw up the menus (later in the appearance menu)

This fixed several problems. My gui is now the exact correct size. I no longer get the funny noise lines that sometimes occur in the Watch Videos and Watch recordings. Some thin horizontal lines are still a little bouncy in some of the menus, but now they are no worse then when I used to use SVideo. I also unchecked deinterlace. I only notice a little tearaway on really fast motion pretty tolerable (except for sports).

With the large fontsize and resized GUI, sitting 10 feet away from the TV I notice almost no bounce,jitter whatever in the GUI.

On another note with myth 18.1 XVMC seems pretty stable. I only see the flickering menu problem, but I can now watch live football like I am using a setup HDTV tuner.

Some dead ends I found along the way. The XRANDR functionality almost seemed to work. I resized the desktop to 960x540 and was happy for a while. The I tried to delete a program and the dialog popped up way in the lower right mostly off the screen. DVI seemed to be a dead end. Hmm I just thought of something, maybe with this setup I can get DVI to work. I'll have to try that later. I don't want to screw anything up for Lost tonight. I'll post my results in this thread when I try it.

So in conclusion, these steps may be obvious to many people, but it took me a lot of playing to find my solution.

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FRONTEND 1 - R5A16, Athlon 3000+, NVidia Motherboard, SB live, GeForce 5200, AA 9A60
FRONTEND 2 - R5A16, Athlon 2500+, Nvidia Motherboard, SB Live, GeForce 440MX, TV-OUT
BACKEND - R5A16, Althon 1700+, Nvidia MB, 2- HD3000's, 450GB LVM partition

this is definitely good information. I know when I was using 1080i I unchecked deinterlace, and never saw any problems even in sports or 720p shows. thats one thing I really liked about 1080i it displayed everything correctly, except the menus.

As far as the XRandR stuff goes I played with that a bit too, and it seemed to work fine for me, other than the fact that it didn't appear to get the video geometry correctly from the video so always used the default resolution no matter what I played. I though it would be great since my tv supports all the modes to have 480i play at 480i 720p play at 720p and 1080i play at 1080i, alas no such luck. I suppose some work needs to be done on the detection code, but I never had a chance to look at it.

_________________
Have a question search the forum and have a look at the KnoppMythWiki.

Xsecrets

OK now I remember why I don't use the DVI output for 1080i. The screen bounces up and down like 1/32 of the entire height. I really need to write this stuff down somewhere so I don't do things 3 to 4 times over.

What I want for Christmas is a nvidia driver that does 1080i properly, maybe a correctly working DVI port as a stocking stuffer. A guy can dream

_________________
FRONTEND 1 - R5A16, Athlon 3000+, NVidia Motherboard, SB live, GeForce 5200, AA 9A60
FRONTEND 2 - R5A16, Athlon 2500+, Nvidia Motherboard, SB Live, GeForce 440MX, TV-OUT
BACKEND - R5A16, Althon 1700+, Nvidia MB, 2- HD3000's, 450GB LVM partition

I use FX5200 VGA -> 9A60 -> TV. Here are the modelines I use. Effective pixels are "856x480" and "1712x960". With these modeline, desktop fit almost exactly to my TV screen.

ModeLine "960x540p" 37.26 856 936 1040 1104 480 522 536 563 +hsync +vsync
ModeLine "1080i" 74.52 1712 1872 2080 2208 960 1044 1060 1125 interlace +hsync +vsync

Is it only the gui that doesn't look good with dvi or is it playback as well?

I hear you I don't have dvi, but using the 6629 drivers I get really bad flicker on the white menu items, not the whole screen. This problem appears to go away in the newer drivers, but the big black bar down the center of the screen pretty much sucks.

Lets all cross our fingers and hope they fix this problem that nvidia (not to long ago) claims they've never heard about for the 8xxx drivers that are due out very soon.

_________________
Have a question search the forum and have a look at the KnoppMythWiki.

Xsecrets

I don't remember. I guess I'll have to do it for the 5th or 6th time. The gui was so bad though that it was unusable. rkshack if you are planning on doing some digging into the code to search for the problem, I'll be happy to give it another try. If it's just idle curiosity,I'd rather spend 15 minutes on something else.

_________________
FRONTEND 1 - R5A16, Athlon 3000+, NVidia Motherboard, SB live, GeForce 5200, AA 9A60
FRONTEND 2 - R5A16, Athlon 2500+, Nvidia Motherboard, SB Live, GeForce 440MX, TV-OUT
BACKEND - R5A16, Althon 1700+, Nvidia MB, 2- HD3000's, 450GB LVM partition

Thank you for your effort. I want to build a box for my new hdtv. I was starting to order parts until I saw the problems with good hdtv video. Before I spend the money on the parts I was trying to find out if it is possible to have myth tv show high quality hdtv. It does not need to be through dvi but that seems the most convenient interface. I just don't want to spend time/money on the project and then get poor or only fair video quality on my hdtv. I asked my question because in general poor quality is ok on the gui providing the playback is very good or excellent. I am very experienced in building pc but a total newbie in linux. I can hack a tivo but that is my only linux experience. So I just was trying to find out if it is worth doing. Any thoughts would be great.

Rkshack

From my own experience, the quality I get from my AA 9A60has been good to pretty good. What the 9A60 does is convert a VGA signal to component video. You are converting an analog signal to another analog signal. Yes DVI would theretically be better because it is digital, but how much better is a good question.

My Sony 46Wt510 looked very good and very crisp using the 9A60 and 540p. But I knew I wasn't watching at full resolution. For my personality that is something that just eats away at you. The newer nvidia drivers gave me a peek at how good 1080i could look, but there's just a large problem with the screen wrapping around the edge and back. Once nvidia fixes that problem I think 1080i will look very good. Now the DVI bouncing i'm not sure if that is my modeline, my graphics card, the nvidia driver or my TV.

I think if you compare a Settop HDTV box with DVI output with the current output of MythTV, you are going to notice some degradation. I think it is very watchable though. You have to ask yourself if going from a perfect picture to a very good picture is a good trade off for the features you gain with mythtv. In my opinion it is a resounding yes. I watch zero live tv. I can't even understand why anyone would want to watch live tv. I guess sports is the exception. But in that case I just start recording it and watch the recording (For some funny reason it takes more horsepower than my system has to watch live tv, but watching a recording while it is being recorded works just fine)

Now this is a little off topic for the HDTV section, but have you considered Standard definition programming over HDTV. I would say that 70% of what I watch is Digitally broadcast SDTV. I've read and listened about people having a lot of problems watching SDTV on their HDTVs. That the quality looks bad. I think most of the problem is due to using a non crt based TV (plasma, LCD, LCOS,DLP) The rest is due to crappiy upconverting by the TV. I listen to the HDTV guys podcast and they POO POO CRTs all the time, but I think realistically less than 30% of the TV shows are in HDTV. So realistically how good SDTV looks is more important. I would have to guess that since you are looking at 1080i thread that you bought a crt based TV.

As an unexpected benefit. SDTV looks better on my Mythtv box than through the tuner on my HDTV. I'm sure it is because the computer is doing the upconverting.

Anyway...

_________________
FRONTEND 1 - R5A16, Athlon 3000+, NVidia Motherboard, SB live, GeForce 5200, AA 9A60
FRONTEND 2 - R5A16, Athlon 2500+, Nvidia Motherboard, SB Live, GeForce 440MX, TV-OUT
BACKEND - R5A16, Althon 1700+, Nvidia MB, 2- HD3000's, 450GB LVM partition

I have a sdtv tivo. I started to get interested in this project because I bought a plasma. I got a panasonic th-50px50u. I love watching the hd content. I want to use the myth box to record my hdtv because with 2 small kids I never get to watch live tv. My local cable company uses a motorola dct 6200 for their hd pvr. Reviews have said its hd output is very good. I am considering using the asus nvidia 6200 extreme tc for my video out. How good should I be able to get the output on a plasma tv. It has hdmi/dvi, svideo and the rgb type component video. It can run 1080i, 780p, 480i, 480p. I think it does not have the 1080i as native resolution but scales up. It does tell me that the show is being eceived at 1080i though. So how good should a signal should I be able to put out.

rkshack