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View Full Version : Interlacing problems with Radeon capture

Franky
19th March 2009, 11:59
I've been using my Radeon x1800 to capture VHS for quite a while now, but recently, something strange has happened. My usual workflow look like this:

1. Capture using VirtualDub to MJPEG AVI.
2. Frameserve through AviSynth using this script:
loadplugin("Convolution3DYV12.dll")
avisource("capture.avi")
converttoyv12()
separatefields()
even = selecteven(last).Convolution3d(preset="vhsBQ")
odd = selectodd(last).Convolution3d(preset="vhsBQ")
interleave(even,odd)
ColorYUV(levels="PC->TV")
weave()
3. Encode to MPEG2 using HC.
4. Author to DVD using TMPGEnc DVD Author.

Up until recently, this has worked fine. But suddenly, it seems that something strange has happened. All my captures seems to be deinterlaced, and deinterlaced badly, somewhere along the way, and it looks like it's in the first step. It's very obvious every time there's subtitles on the screen, as they seem to vibrate. I suspect something is wrong with my video card. I've tried downgrading my drivers but with no effect.
Guest
19th March 2009, 13:28
Post an unprocessed source sample.
Franky
19th March 2009, 21:44
Here you go:
http://www.megaupload.com/?d=9W5CHVOE
reepa
20th March 2009, 15:36
The top field has been swapped with the bottom field. Just insert SwapFields() right after AviSource().
Franky
20th March 2009, 23:30
Sorry, doesn't work. Swapping the fields make subtitles look better, but the video itself starts skipping.
Guest
21st March 2009, 00:05
It's progressive PAL with phase shifts. So you can do this:

avisource("test.avi")
telecide() # fix phase shifts by matching fields
converttoyv12(interlaced=false)
Convolution3d(preset="vhsBQ") # progressive so no need to separate
ColorYUV(levels="PC->TV")
reepa
22nd March 2009, 02:08
Sorry, doesn't work. Swapping the fields make subtitles look better, but the video itself starts skipping.

If it skips, then you also need to add ComplementParity() right after AviSource, whether you use neuron2's solution or mine. Your sample can be made to look nice with SwapFields() without skipping.
Guest
22nd March 2009, 02:17
SwapFields() here puts fields in the wrong spatial positions.
reepa
22nd March 2009, 02:24
Maybe my decoder (ffdshow) is configured wrong, but I assumed it was his problem too since swapped fields make subtitles look especially bad.