Please Help, 33% dropped frames!

[bchball]

I am trying to capture from PAL TV using Virtual Dub at 352x288 and no matter what codec i use to capture with, i get a large amount of dropped frames (huffyuv, divx, etc.). I have also tried different audio compression and get the same result.

I use:
WinXP Pro
AMD XP2000+
256meg DDR2100
Geforce2 GTS Deluxe (for capture)
Creative SB Live!
IBM 7200rpm HDD

Also when using VirtualDub the bottom of the picture is chopped off and don't know how to fix it.

Would be extremely grateful for any hints/ideas about how to solve these problems.

[Fozzee]

Hi
I haven't used it in ages but.......
I sem to remember the default frames per second is 15 I think.
This caused loads of dropped frames for me.
If you are capturing to Pal you need 25FPS.
Try adusting that and see how you get on.

Fozzee

[bchball]

I was using 25fps and also get many dropped frames as 15fps. Also Virtual Dub's CPU usage does'nt go over 30%.

I have also tried using Win98 and get the same results.

[bchball]

Well i'll be stuffed how that happened. I got home from work and thought I would give it one more try. For some strange reason it works perfectly now, no dropped frames, capturing at 25fps instead of 16.99998@25fps and i'm getting the whole picture without the bottom chopped off. All I did was to unplug and plug the leads from the vid card and amplifier and started VDub from the AuxSetup.exe although I can't see how any of this would have made a difference.
Anyway, i'm BAAAACK! yeha.
If I notice anything else to determine what happened i'll post it here.

[lpn1160]

You don't say what format you're capping to, so if you are capping to RGB try YUV (YUY2) interleaved, settings in advanced format in vdub, then in huffys config box switch to "convert to YUY2". Audio should ALWAYS be capped UNCOMPRESSED!!! Compressing audio, beleive it or not during a capture can cause dropped frames. If this works you should then attempt to up your cap res to 352x576(PAL). capping both fields gives much better results

[bchball]

Thanks Ipn, but I can only capture in UYVY YUV 4:2:2 Interleaved. The other settings like RGB give me an unsupported format error and when I change the depth to 576 it just increases the black above and below the picture.

[rijnoutgankema]

Hi,

To solve your "unsupported format error" try the Brooktree´s Bt8xx WDM driver. At least if you use a BT8xx capture card.

see http://btwincap.sourceforge.net/

regards,

Rijnout

[kenmo]

I would NEVER recommend those btwincap drivers. They are EVIL (although well intended)...

[bchball]

I found out why!
On restart of pc the cap drivers are possibly set to NTSC. I installed PowerVCR II and it is set by default to U.S.A. standard. By changing it to Australia PAL-B then closing the PowerVCR II application and starting Virtual Dub everything is ok because this somehow changes the driver settings to PAL hence not getting bottom chopped of picture and dropping heaps of frames.
I'm still having a little trouble capturing VHS once it goes more than 2 min into it. I get a bunch of about 5 dropped frames every 20 seconds and it shows in the finished avi by stuttering where it missed the frames. I think that I need to capture to a dedicated empty HDD as I was trying to capture to my local drive which is the only one I have that has plenty of space.

[xmann]

I found out why!
On restart of pc the cap drivers are possibly set to NTSC. I installed PowerVCR II and it is set by default to U.S.A. standard. By changing it to Australia PAL-B then closing the PowerVCR II application and starting Virtual Dub everything is ok because this somehow changes the driver settings to PAL hence not getting bottom chopped of picture and dropping heaps of frames.
I'm still having a little trouble capturing VHS once it goes more than 2 min into it. I get a bunch of about 5 dropped frames every 20 seconds and it shows in the finished avi by stuttering where it missed the frames. I think that I need to capture to a dedicated empty HDD as I was trying to capture to my local drive which is the only one I have that has plenty of space.

ree: rchball 33%dropped frames

i do it just like you first starting power vcr then close it to avoid dropped frames in virtualdub but ther most be a easy way of doing it.


any help ?

sorry my bad english