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glennpierce
January 29, 2007, 19:11:18
Sorry. One final problem.

I am trying to record at the same time as painting to a window.

I am running the sample program CreateVideoFile. However, when I move my hand across the camera fast I get horizontal lines appearing over the paint window.

The IC Capture program does not do this while recording.
Does IC Capture do anything more advanced ?

Thanks for all the help.

Glenn.

Stefan Geissler
January 30, 2007, 09:12:48
Glenn,

I would identify the horizontal as interlacing lines, produced by your analog camera. IC Capture should show these lines too, because it uses exactly the same technique. There is nothing more advanced.

Stefan Geissler
January 30, 2007, 09:12:49
Glenn,

I would identify the horizontal as interlacing lines, produced by your analog camera. IC Capture should show these lines too, because it uses exactly the same technique. There is nothing more advanced.

glennpierce
January 30, 2007, 11:38:29
Thatís what I first thought but having asked a few people IC Capture definitely doesn't produce these lines on fast moving objects.
Unfortunately I can't get a screen grab of the effect. I have noticed a difference between IC Capture and the CreateVideoFile sample. Under windows task manager I have two cpu windows due to my processors hyper threading.
IC Capture utilises both of these when recording but when running the sample only one shows any activity. Maybe this is a clue ?

I could maybe get another camera and try to record the effect if you think it will help.

Thanks

Stefan Geissler
January 30, 2007, 12:57:48
Hi Glenn,

What camera do you use?
Are the lines horizontal and are thay 1 pixel thick?
Do you use a laptop, and if so, what kind of laptop?

glennpierce
January 30, 2007, 15:08:54
Its an anolog sercurity camera working though the video to usb converter
DFG/USB2-It I will hunt around for the exact model of the camera.

I am working from a desktop machine
pentium 4 2GB Ram.

The horizontal lines are greater than 1 pixel, they are not sharp their intensity seems to decrease from the center.

When moving my hand fast across the camera I get about 20 horizontal lines around the area of my hand spaced at around 8mm.

I am capturing with UYVY 768x576 Composite

Interesting when recording my screen using a desktop movie grabber app the problem doesn't appear on the recording in the same way. Then the lines are about 1 pixel and do look like interlacing.

Thanks

glennpierce
January 30, 2007, 15:30:12
I have just tried with another camera.
A cohu 2700 series black and white camera but have the same problem.

Stefan Geissler
January 31, 2007, 12:05:05
Hi Glenn,

You encounter usual interlacing artefacts. This is a problem of analog cameras and not easy to fix. Also IC Capture has no special things in to reduce deinterlacing.