G400TV capture quality Vs Rest Of World

[DrP]

As you might know, I'm in the process of replacing my trusty G400TV. I'm doing it for two reasons 1) want better graphics performance 2) the tuner in the BOB is on the way out and getting severe herring boning on the pic (PAL fault).

Does anyone know of a capture card (prefer standalone rather than a combo display / capture) that does the same quality captures as the G400TV. Here's a couple of clips from frames that were captured concurrently with the G400TV and a WinTV 647 (BT878a). Both were sourced from the same video signal (the G400TV was simply aligator clipped onto the video out from the WinTV and set to composite mode). The captures were done with huffyuv. As you can see from the pics attached, the Matrox kicks the WinTV all the way down the street and back.


hmmm, ok so you cant attach two files. look here for the pics instead..

http://members.dingoblue.net.au/~alfalfa1/matrox.bmp

http://members.dingoblue.net.au/~alfalfa1/wintv.bmp

[Indiana]

I don't know what went wrong there, but I do not get such a blurry picture when capturing with my WinTV.
You can look at a few examples of vidcaps with my WinTV:

http://www.indiana.claranet.de/Werbung1.jpg

http://www.indiana.claranet.de/HotShots1.jpg

http://www.indiana.claranet.de/HotShots3.jpg

The noise in those caps is unfortunately how my TV antenna signal-quality is, but still they don't have this blurry filtered look - even though those were capped with MJPEG and are recompressed to jpg for size reasons (thus being double jpg-compressed which is very liekly to blur things).

Do you deinterlace while capturing?

[DrP]

its a CIF capture, so no deinterlace required. The Matrox sample was done with AVI_IO, WinTV with iuVCR. All codec and resolution settings in both programs were the same.

[Indiana]

I'm still wondering how you get that NVidia "blur-vision"™ look. I had captures that were similarly blurred (but still not that bad, I think) when I used the input of my RadeonVIVO - which is why I've never used it but the much better hauppauge instead. Maybe it's a NTSC vs. PAL issue?

[AndrewDV]

Hello,

WinTV 647 - which model is that?

iuVCR? Doesn't that require WDM drivers (which would explain why AVI_IO was not used)? If so, ditch it. The VFW drivers are MUCH better.

It looks like the images up top are:
-1 field capture
-The fields have been swaped (remember the G400-TV is opposite the WinTV in field order).
-Using the WDM drivers.

One "trick" that any WinTV user should be aware is to turn off both overlay and preview options. That allows a 2 field capture. If you don't do that, you get 1 field only no matter what you set in AVI_IO or the codec.

[DrP]

Tested using the WinTV VFW drivers. Same blur effect.


A 647 is PAL, Stereo (NICAM for the UK too).

Yes, iuVCR uses WDMs. The PC actually had two active captures - one via VFW + G400TV + AVI_IO, the other WDM + WinTV + iuVCR.

I've tried the WinTV VFW drivers, but can't seem to get AVI_IO to present a channel select GUI, so unless I start a 3rd party app first, it aint gonna be easy to set the channel to record from (I've have written a kixtart script to do timer recordings etc, works well)

I'll use the WinTV VFW and do a quality comparison.

Yes, its a single field capture CIF PAL - both the WinTV and Matrox were doing CIF so field order doesnt really come into it. The logo is the same resolution and sharpness on A or B fields from the broadcast.

[DrP]

For anyone who's interested, the problem is with the Hauppauge driver in general (VFW / WDM). They are setting the BT to do a rather blurry capture. If the wdm drivers at btwincap.sourceforge.net actually ran my card properly, I'd be using them in a flash.

[Dr Mordrid]

I've seen compalints of blurriness with several PAL analog capture devices so perhaps some of the "blurriness" is due to PAL's alternate line encoding.

In NTSC things look pretty sharp.

Dr. Mordrid

[DrP]

You're probably right. The BT is probably averaging the luminance a bit as well as the chroma when doing PAL decodes. The driver from btwincap.sourceforge.net allows adjustment of the sharpness level of the BT or perhaps a minor miracle will occurr and Hauppauge will write the feature into their driver.