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View Full Version : What manner of noise is this (and what do I do about it)


superfrosty
29th August 2005, 17:19
When capturing video on to my PC from VHS, i often get a large, white line at the top of my screen. It only last a frame or two, but it is a commen occurace. Looks like this
http://img179.imageshack.us/img179/4464/noise26bb.png (http://imageshack.us)
The picture comes from an A&E movie taped off cable on a different vcr. My capture card is an ATI ALL IN WONDER 9700, recorded with ATI TV
Can someone please tell me what the problem is, and how to deal with it?!
Thanks in advance.

mic
29th August 2005, 19:21
The picture comes from an A&E movie taped off cable on a different vcr.
Personally suspect tracking prob from one vcr to another. Might try manual tracking adjustments, or worse case, if it happens at different times (randomly) capturing twice and patching from one to the other in an NLE. Easiest way is if you could borrow original vcr.

superfrosty
29th August 2005, 19:28
Easiest way is if you could borrow original vcr.
Um...can't borrow the vcr, its 200 miles away in Long Island :( .
Doesn't look like tracking, b/c adjusting the tracking does nothing helpful. The problem appears in the same spot each time I record, so i don't think recording twice will help. I am using composite cables...would a co-ax connection fix the problem?
If not, any VDub filters that will help?

mic
29th August 2005, 20:37
The easy way to verify if it's something with your ATI card or the vcr / tape is if it's something you see on TV when you're playing it. S-Vid cables would be better then composite would be better then co-ax if that helps.

To me it looks like the video signal got lost or damaged, perhaps a bad section of tape, maybe the original broadcast, maybe because the vcr heads are reading the tape a bit differently then the original vcr's & this is a marginal or dirty section of the tape, that sort of thing. It might not hurt to try the tape in another vcr, but you might be stuck with it.

If so, what I'd suggest is editing it out. If it's 3 frames or less, you can copy the before and after frames over frames 1 & 3, blend the two at 50% transparency for number two. If it's 2 frames, just copy before and after and so on. This appears to be an intro (Rating showing), so hopefully it's pretty static and won't notice.

Another method would be to eliminate the scene (should just be a few seconds), but then you should blend the audio cuts -- not difficult, but better in an NLE where you have tracks and can blend audio.

In V/Dub or NLE you could make a copy of that scene, crop and enlarge it, then replace the original. Easier in an NLE, in V/Dub I think I'd direct stream copy up to the cut or split, repeat it for the cut, then repeat it for the remainder. After fixing the scene and rendering it, I'd import all three appending 2nd and 3rd pieces, then render.

superfrosty
29th August 2005, 22:19
Thanks, its just one frame so i can delete it in VDub, although this problem isn't specific to one spot or one tape--you're right, it's probably the difference in VCRs. Different problem, but in the same movie:
http://img331.imageshack.us/img331/7328/lines23ir.png (http://imageshack.us)
streaks across the video. This can last for minutes at a time, so frame deleating/repeating won't work. I can live with it, but wonder if a filter can help me out. Again, this isn't specific to just one tape/movie.

mic
30th August 2005, 00:53
Don't delete the frame -- copy one over it if possible. Won't notice the repeat, but helps keep everything in sync. 1 frame isn't a big deal, but bad habit to get into. :) Personal opinion anyway. :):)

This isn't as bad, & I think filters can help, but they have their cost too... If you blend to cover up a streak or band, you also tend to blend everything else for example. I think if you could post a sample clip in a new post asking for specifically for filter advice in the title, you'll get a few more responses, opinions.

jaymanchu
6th September 2005, 00:39
I have this EXACT same problem and was getting ready to post a question like this as well. My problem is worse though as the picture likes to jump around and gets distorted as well. Every once in a while. It's definately NOT a tracking problem as I can play this on the same VCR through my television with NO problems. I can record this on my set-top DVD recorder but the quality sucks (very pixelated). Here's what I get when I try to capture "The Gong Show Movie":

http://www.freewebs.com/yodakiss/gong1.jpg

http://www.freewebs.com/yodakiss/gong2.jpg

http://www.freewebs.com/yodakiss/gong3.jpg

mic
6th September 2005, 02:50
I have this EXACT same problem and was getting ready to post a question like this as well. My problem is worse though as the picture likes to jump around and gets distorted as well. Every once in a while. It's definately NOT a tracking problem as I can play this on the same VCR through my television with NO problems. I can record this on my set-top DVD recorder but the quality sucks (very pixelated). Here's what I get when I try to capture "The Gong Show Movie":
Edit: Your links or pix didn't show in post.
At 1st anyway...

But they are nasty. How are you connecting your vcr to your capture hardware, & what sort of hardware is it? Looks to me anyway like bad signal, maybe copy protection on tape if retail?

setarip_old
6th September 2005, 03:23
maybe copy protection on tape if retail?

Or, possibly, copy protection on a Pay-Per-View channel...

jaymanchu
6th September 2005, 14:26
It's not copy protected, even if it was I have a Sima Copymaster. I am using and XP Pro box with 512 Megs of RAM, ATI All-In-Wonder 9200 capture card, and monster cables. I have tried changing cables, VCRs, even had this problem on my old ATI card. This problem doesn't exist when I plug straight into a tv. Only when I try to capture it on my PC.

mic
6th September 2005, 23:46
Well... the way copy protect usually works with tape is to reduce the signal quality, so while it will play fine on TV, the signal is too poor to be recorded. (that's the quick version anyway :)).

I'd suggest trying to capture broadcast or cable directly, using your vcr as a tuner. If that checks OK, cables etc. are probably OK, so then try recording regular broadcast, cable, or sat etc. to a new tape in your vcr. If you can capture this ok, that would point to bad or protected tapes. And FWIW, might also want to try it without the Copymaster.