Capturing pc to usb encoding device through vout?

2006-06-10 10:40:14 am

I'm trying to find a way of capturing videos without slowing my pc down (tried fraps).
The way that seems best the moment would be to use the TV-out of my X800 XL card and connect that through s video to a usb device with hardware encoding which is connected to another pc. This way I shouldn't get dropped frames..

I'm considering this capturing device since it supports mpeg4 hardware encoding:
Plextor ConvertX PVR PX-TV402U

My questions:
Good idea so far?
What happens with the big resolutions (1600*1200) I'm playing at? Does the TV out or the plextor scale that down?

thanks,
felix

Thread title:

Radix

2006-06-10 01:49:57 pm

I'm addicted to games

Anything sent out on s-video would get scaled down to an analog 720x480i 59.94 fps picture... could make it look crappy. But probably still etter than recording the game in 640x480 with fraps and getting 10-15 fps.

felixjo

2006-06-10 02:12:51 pm

I suppose it wouldn't look too bad as long as the scaling technique is reasonable.

Are you sure that the ati card will put something on tv out?
I'm a bit afaid that it will only do it on low desktop resolutions, that would make the whole thing pretty boring.

felix

ballofsnow

2006-06-10 02:16:28 pm

My ATI Radeon 9800 has tv-out and it works. I think you need to have the ATI Catalyst installed to be able to turn on the tv-out.

felixjo

2006-06-10 03:08:04 pm

Did you try capturing at high in-game resolutions?

ballofsnow

2006-06-10 09:38:20 pm

Quote:

Did you try capturing at high in-game resolutions?

Quote:

Anything sent out on s-video would get scaled down to an analog 720x480i 59.94 fps picture....

nate

Edit history:

nate: 2006-06-10 10:15:41 pm

2006-06-10 10:15:24 pm

it will definitely be acceptable for this site if you can avoid vhs. it'll be 640x480 60 fps (assuming the game is in fact running at 60 fps), and it won't look as good as fraps at 640x480 60 fps, but it'll be decent.

felixjo

2006-06-11 01:46:39 am

Well, I don't know if I formulated the problem in an understandable way.

The problem is that at least some cards apparently only put out an s video signal if you have your card set to 1024*768, maybe they can't scale the image down if you use higher resolutions.
A friend told me that they had to play at a lower resolution than normal to record a video with a capture card because of that.

nate

Edit history:

nate: 2006-06-11 05:15:57 am

2006-06-11 05:15:17 am

well, the resolution is more or less irrelevant when it comes to analog (disregarding the ntsc/pal cleavage). do you have an analog tv to test with? if you can see a picture on the screen, then you know a good analog capture card will capture it. with the capture card you'll be capturing in 640x480 regardless of what the output resolution was.

felixjo

2006-06-11 08:40:09 am

I would need a s video to scart adapter to connect them directly.

I'll play when I record, that's why I care about the resolution. I know that my tv out will only put out PAL resolution.

felixjo

2006-06-15 09:48:38 pm

I've got the plextor capture x usb this week.
So far it seems to work rather good.
Setup was easy and it converts mpeg 2, divx, vcd and mpeg 4 in hardware. Sound wise you can get mp2 or mp3, depending on the video codec.

I tried all formats, for some reason highest quality (6000kbit/s) mpeg2 doesn't work, I emailed Intervideo (maker of win dvr) and plextor today, maybe they know what to do about that...

This works with the tv out up to 1024 * 768 ingame resolution. I've ordered a Grandtec Ultimate XP scan converter which can scale a vga signal (up to 1600*1200) down to a pal or ntsc signal. This way it should be possible to play at high resolutions and still record in tv format.

I'll probably use the dvi out to for the scan converter and capture device, this way I don't have to use the pass-through stuff...
Maybe the quality will be better since the built-in video out is of poor quality?

nate

2006-06-16 01:10:49 am

wow, i think it's safe to say this is the furthest anyone has ever taken this capture method here at sda.

felixjo

2006-06-16 04:06:23 pm

I've tried out the Grandtec Ultimate XP Pro PC to TV converter.

It seems like using the dvi out with this converter doesn't provide better quality.
Connecting the convertX directly to tv out (with s video) gives a clearer picture.

Check 85.88.7.188 for test images.
1.bmp (1024*768 scaled by ultimate xp),
2.bmp (1600*1200 scaled by ultimate xp) and
3.bmp (1024*768 scaled by sapphire x800xl)

One possible use for the scan converter would still be the possiblity of playing at high resolutions, of course. This might be interesting for realtime strategy games...

felixjo

2006-06-16 04:08:03 pm

The images were taken by recording a 4500kbit/s mpeg 2 stream and then saving the bitmap in movie player classic.

nate

Edit history:

nate: 2006-06-17 12:26:35 am

2006-06-17 12:24:00 am

yikes yeah. got some serious chroma issues in 1 and 2 there (compare the "black"). definitely prefer 3.

und es war eine überraschung, eine deutsche fehlermeldung zu sehen. Wink

especially when you speak such good english.