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View Full Version : Trying to remove black lines from low quality NTSC to PAL conversion

oledoe
13th March 2004, 17:38
I'm capturing from a cable tv channel that presents a black line every two lines, that is:

IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII
IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII
BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII
IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII
BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII
IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII
BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB

I guess they converted NTSC sources to PAL using a low quality converter box.
From previous posts I learned it's impossible to undo the field blending, but I'd like to remove the black lines before compressing to XviD.
I would appreciate any ideas.
scharfis_brain
13th March 2004, 21:22
this should be possible with some kind of spearatefields-weave combo.

would you please make a short - clip of this available?

btw. the fieldblending can be made undone (with some limitations) using restore24
oledoe
14th March 2004, 21:07
Hello, Scharfis Brain.
My computer with a tvcap card is down at the moment, so all I can provide is a couple of 384x288 single field images.

web page with PNG Images (http://www.geocities.com/juanpablodoe/remove-black-lines/index.html)

Thanks for the restore24 suggestion, but I'm willing to live with the blends because most of the footage I want to capture from this source is music video clips, and I think they must be interlaced from the start. Besides, I tend to capture only single fields, because I have little experience with deinterlacing and IVTC.
scharfis_brain
15th March 2004, 00:57
at first, I do not think that those darker (not black!) lines are crap from a bad NTSC -> PAL transfer.
but with a short example-clip (2 or 3 secs) I should be able to write a script that is able to repair this.

They might be caused due to a bad reception of the Antenna or interferences of the TV-card.
Is everything on this channel lined like your examples or just a few clips.

btw. pleeeeeze do your caps at 7xx*576. Else you'll get annoying stutters every second on standard-converted videos.