Cant get higher captures

[craigarta]

I am running Xp with the following:

Asus A7A266 board
1.2 Ghz Thunderbird
512 DDR ram
Hauppage 401 WinTV

Now when ever I use Virtualdub it only lets me capture at 352 x 240 with the Huffyuv compression at 24 RGB. Any other setting I always get unsupported format. I am running the latest drivers.

Is there some setting I need to tweak?
Or should I try some other program?

[mpb]

I am running Xp with the following:

Asus A7A266 board
1.2 Ghz Thunderbird
512 DDR ram
Hauppage 401 WinTV

Now when ever I use Virtualdub it only lets me capture at 352 x 240 with the Huffyuv compression at 24 RGB. Any other setting I always get unsupported format. I am running the latest drivers.

Is there some setting I need to tweak?
Or should I try some other program?

Don't use 24RGB setting. Use:

UYVY YUV 4:2:2 interleaved.

That will allow you to use any resolution you want, with most capture cards. Capturing with more than 480 horizontal usually is meaningless, though, since that's all the lines of signal you'll be receiving.

[wway]

Capturing at more than 480 horz resolution is not meaningless. I can not give you the exact technical reasons, but i know from experience that a 640x480 capture encodes to a lower overall quantization value than a 480x480 capture.

I remember reading a post from someone explaining why this is true. Maybe one of the moderators can offer a better explanation (SKittelsen, Truman, Vitualis)

wway

[BJ_M]

just a note to not confuse pixel with lines .. a general rule of thumb is that lines equal 75% of pixels

hence 720 pixel = 540 lines , so 480 lines equals 640pixels

capture at 640 x 480 is about the max possable of information you can get from ntsc signal , but , just like oversampling - by going futher than this will yield better quality ..

DVD's and svcd are always 4:2:0 chroma value , DV is 4:1:1 and 500 line (480) .. while at the other end of the scale VHS is only 240 lines

capture in 4:2:2 wille certainly give you a lot better over all colour .. though you have to convert it with your encoder ..

[craigarta]

Thanks All now it makes more sense to me.