Problems capturing computer screen through component

[Titan91]

I'm wanting to capture my computer screen via component out using the Hauppauge HD PVR. I know this sounds silly, but I'm doing this to capture HD gaming footage as I don't have a RAID HDD array. I have a NVIDIA GeForce 9600GT video card outputting in cloned dual monitor mode via VGA and a component breakout cable. My HD PVR is capable of capturing component signals at up to 1080i. So essentially I want to record my screen without taxing my computer's CPU and HDD, as the PVR has seperate hardware video encoding. I got this to work, but with 2 problems:

First, when outputting to the PVR at 720p pretty much any video mode higher than 1024x768 shows distortions in the image coming out through the PVR's component output. It can get so bad that the PVR actually loses sync with the signal and drops the image, sometimes not grabbing the signal again until I change modes. This also happens with 1080i but not as often.

Now keep this in mind: My video card handles video output via component in two different ways. It first allows me to select a common mode, such as 1080i, 720p, etc. to be sent over the component cable. Secondly, when I change my system resolution either through desktop proerties or the NVIDIA control panel, the card will scale the image to fit the signal going to the PVR over component. The component video mode doesn't change no matter what I set my system resolution to. This video mode conversion is why I see distortions on my PVR with high-res modes that otherwise wouldn't be present in low-res modes. So basically with 720p and 1080i going to the PVR over component, my results change depending on what I set my system resolution to.

I can avoid the video distortion problem by using a low system resolution, but doing that defeats the purpose of this setup in the first place, since captures wouldn't really be HD. I have yet to find out what the actual cause for these image distortions is, I'm thinking it's NVIDIA's drivers and not the PVR, since the video mode going to the PVR never changes. Has anyone else ever had this problem? I know this is a pretty particular issue and may be hard to recreate.

My second problem with this setup is the image going to the PVR is always overscanned, meaning pixels all around the edges are cut off. I can fix this by adjusting the edges with the NVIDIA control panel, creating a custom resolution. However, the resolution is modified from 1080i (or 720p), meaning it's high-res, which won't work because of the first problem. So unless I get the first issue fixed I can't use NVIDIA's image scalar to fix the overscan. Is there any way of making the image size going to the PVR correct without having to create a custom video resolution?

Thanks for reading, this is a bit of a complex problem. If there's any way you can help, please post. Thanks again.

[psyfect]

First, when outputting to the PVR at 720p pretty much any video mode higher than 1024x768 shows distortions in the image coming out through the PVR's component output.

720p in computer resolution is 1280x720. I know you said 'any,' but on the off chance you skipped this one, I'm mentioning it.

The component video mode doesn't change no matter what I set my system resolution to.

So basically with 720p and 1080i going to the PVR over component, my results change depending on what I set my system resolution to.

These two thoughts are conflicting, but you should set your computer resolution to 1280x720 (to record in 720p).

If you haven't already, record a test video and play it back. If you're just looking at the preview window within the arcsoft application it may be scaling the preview to fit the window.

How does it look when you switch between a low resolution (which you said is fine, but not hd) and 1280x720? Perhaps you could upload two comparison videos?

[Titan91]

720p in computer resolution is 1280x720. I know you said 'any,' but on the off chance you skipped this one, I'm mentioning it.

It still happens when I set my system resolution to 1280x720. Actually, this is probably the worst mode for this problem.

These two thoughts are conflicting, but you should set your computer resolution to 1280x720 (to record in 720p).

They don't conflict, I'm saying the results change depending on my resolution, not the video mode going to the PVR.

If you haven't already, record a test video and play it back. If you're just looking at the preview window within the arcsoft application it may be scaling the preview to fit the window.

Actually I tried that to visualize the problem. And believe it or not, there was no distortion in the video! It looked pretty much perfect, no horizontal stretching or blacking out. I concluded from this that it's a problem with the PVR passing the signal through, but it doesn't affect the recorded video. I e-mailed Hauppauge about this and should get a reply next week.

How does it look when you switch between a low resolution (which you said is fine, but not hd) and 1280x720? Perhaps you could upload two comparison videos?

I basically have a perfect picture with the lower resolutions, but overscanning is still a problem.