Ghost Images At Edit Points

[rezzodog]

I've done a lot of analog capturing, but this is a new one on me. Using a variety of capture programs (VirtualDub, AVI_IO, ATI TV) and a variety of codecs (Huffyuv, MJPEG, Uncompressed) I am getting these weird ghost images whenever there is a cut in the film. What I mean by 'ghost' is the previous shot and the next shot are overlapping for a single frame just as the shot changes, which cause an odd jump in the video during playback.

Not sure if that describes it very well...it's a strange thing.

Anyway, if anybody has encountered this before and has a solution, I'd love to hear it.

If any additional info would be helpful, please let me know.

Thanks.



-Rezzo

[rezzodog]

I thought showing what I meant instead of trying to describe it would be more effective:




1. Shot One
2. Shot Two
3. Single frame between the two shots, which seems to overlay one on top of the other.


Hopefully this makes it more clear.

Again, any help would be greatly appreciated. Thanks.

[rezzodog]

OK, here's one more important clue. I ONLY seem to have this ghosting problem when capturing from an S-VHS source. I just tried a test using the same S-VHS VCR, but with a standard VHS source, and the ghosts did NOT appear.

Thanks for any help.

[johns0]

Usually that effect is caused by deinterlacing and using blend when you are encoding,the next frame which is supposed to follow is blended in.If that is the case dont de-interlace as it is not needed.If that is on playback of the captured source before encoding then the fields might be reversed and need to be set the right way during encode.

[rezzodog]

Thanks for the reply. Problem is, I'm not doing any deinterlacing at all. This is immediately after capture.

After some more experimentation, here's what I found:

Using a JVC HR-S4600U VCR, I need to have the Image Stablization feature ENABLED. That takes care of the ghosts. Of course, that brings up a different problem. With the stabilzer enabled, the image flickers wildly using an ATI AIW 9000 card. I do not have any flicker using a Pinnacle DC-10+, but the image quality is pretty terrible.

So now I guess the problem is the flickering that occurs with the image stablization enabled on a JVC HR-S4600U capturing with an ATI AIW 9000.

Argh.

[rezzodog]

People aren't exactly pouncing all over this topic, so I have to assume it's unique to my situation/set up. Lucky me.

The ONLY way I've found getting around it was to deinterlace during capture. That made the problem go away, but at the cost of a pretty blurry picture (no surprise there).


Does the fact that the problem goes away when deinterlaced tell us anything?

Thanks.

[Sulik]

It may indicate that this is a playback issue, and not a capture issue (whatever codec deinterlaces on playback is blending both fields).

[ronnylov]

My JVC SVHS video with TBC and DNR does the same thing when the TBC/DNR is activated. There is probably some kind of temporal filter in the digital noise reduction that averages pixels from previous frames to reduce noise. I can't see it at normal playback speed so it's not a big problem for me.