Missing bottom half of video

[heckheck]

I'm wondering if anybody knows what is happening to cause me to lose the lower half of my video for certain types of video playback. I can see the top half of the frame, but not the bottom half.

Some background first.

The SAGE TV application is not currently suffering from this, but DVDs and MPEG4s played through Windows Media player (or Intervideo Media Player) are. SAGE did have this problem at first, but it seems to have cured itself.

The problem occurs when I am using VGA output converted through a color space converter (Key Digital) to display on my 480i component ready Sony TV. The problem does not occur when I use S-Video connection to the TV. Note: To obtain a stable picture with the converter to the component input, I had to use composite sync +H and +V sync settings on the video card and composite sync on the video converter.

My video card is an ATI 7500 video card in 640x480 interlaced mode. Special note (the card has been modified to support very low pixel clocks and has custom resolutions programmed in to support ARCADE video modes, including the 640x480i mode I'm using. I think the same thing -- excepting the low pixel clock, which is a resistor/capacitor change -- could be achieved with PowerStrip).

I know this is a really non-obvious setup, and what I'm hoping is that someone knows a simple answer to my problems. Clearly some mode somewhere is getting confused, since Sage does the video right, but other apps don't. If I can get this working, it would REALLY make my day, since this setup is part of a big project I've been working on for many months to create a PVR/Multi-Arcade-Machine-Emulation entertainment center. PS The transcoded component video is beautiful to look at (BLOWS the doors off SVideo), I just wish I could see all of it all the time!

Thanks for reading this far

heck_heck

[stanger89]

Sounds like the infamous ATI Interlaced overlay bug. Try using Default or VMR9 as your renderer, or, to actually fix it try Catalyst v 3.4, 4.2, or 4.3 (those work for me).

FWIW, on my Radeon 9500, I've run 640x480i (semi-successfully) via PS alone.

[heckheck]

Stranger89,

THANKS! I have confirmed now that you are right on the money. Going back and forth in Sage between Overlay and VMR9, causes and corrects the problem respectively. This explains why SAGE was not having the problem, since I was already using VMR9.

Two questions. Do you know of any way to force Intervideo and/or MSFT Media player to use VMR9? I'd change to one of the newer catalyst drivers, except they probably won't work with my reworked card (I'll give it a try, but the default MSFT driver doesn't work, so I have small hopes). I will report back to the manufacturer (Ultimarc), and ask him to update his special drivers.

Second question, what do you mean by "semi-successful" with the ATI9000? Can it drive the pixel clock low enough to get down to 640x480i, or are you having other problems? I'd like to know if I can hope to drive this video mode if I pick up another card like the ATI9000.

Thanks so much for your help already,

heckheck

[heckheck]

Answering my own question. There is a player that will use VMR9 instead of overlay for ALL kinds of media (DVDs, MPEG4s, MPEG2, etc). Media Player Classic is my salvation. You can find it here

http://sourceforge.net/projects/guliverkli/

This player is amazing. Simple yet powerful. Makes M$FT Media Player 8 and 9 look like .. well I'd rather not say. I'll leave it at this player solves my problems, the others don't and no advertising on startup to boot!

VMR9 (or 7) can be set under View | Options | Playback | Output | Video.

[stanger89]

I can succesfully set my 9500 to 640x480i (Arcade in PS) but the TV seems to loose sync every once in a while like that, not sure if the TV or video card is at fault. I also have the Component Dongle and may have to give that a try for ya, I think it's supposed to support 480i.

[heckheck]

Stranger89,

Thanks for the response. With the discovery of Media Player Classic, I at least have a work around using my current drivers, though it leaves me stuck in VMR9 land (not a bad place, but less options).

Your sync issue might or might not be card related. The main problem with achieving 640x480 i is the low pixel clock rate. If the PLL on the RAMDAC is losing sync occasionally, that could explain your loss of sync. The PLL can lock over a range of frequencies, but the range is skewed to the high side these days to accomodate higher and higher pixel clocks for high refresh rates at mondo resolutions. That is why most modern cards can't get back down to 640x480i or lower. That is why I bought the modified card, since I was going for really low clock rates to support the old video arcade resolutions.

Thanks for your help.

heck_heck