dot crawl is not fun

[HyperSpad]

I capture analog ntsc television through a coaxial cable. What are some good ways to eliminate the additional chroma noise that comes in? I'm mainly referring to DOT CRAWL. This has been a very troublesome thing for me and I'm not sure if it's something that can be better fixed before capturing or afterwards (via filters).

All help is appreciated

Thanks,
HYPERSPAD


(bold text was just edited)

[Mug Funky]

if you have an s-video output on your TV there may be a chance, but all it means is it'll be using the comb filter in your TV rather than the one in your card... it's a gamble to see which is better.

apart from that, DeDot is often very helpful. run it before any other filters, and make sure it gets interlaced frames as input. if the crawls are too horrible then it wont help though.

also, one thing i noticed on my $2 capture card is an auto colour thing which boosts the saturation, but seems to amplify the crawls and rainbows more than the actual picture. if you find one of these, turn it off and DeDot might have a better chance.

[Guest]

What is the best way... Please read and follow forum rules, specifically, rule 12: Do not ask what's best. Thank you.
:readrule:

[HyperSpad]

if you have an s-video output on your TV there may be a chance, but all it means is it'll be using the comb filter in your TV rather than the one in your card... it's a gamble to see which is better.If the quality of the picture I see on my tv is any indication of how well its comb filter performs, then I'd say this is definetly worth a try. Only thing is, keeping a tv near my computer will take up quite a bit of extra space, not to mention that I'd have to buy one with s-video out. I don't think I have one that supports that.

Do you know if VCRs or other types of cable boxes have comb filters built in? I keep hearing about cable boxes that convert the input to s-video out, but I'm not sure if that would do anything for the quality of the picture.


also, one thing i noticed on my $2 capture card...As in you paid $2 for a capture card?!? Which one?


...auto colour thing which boosts the saturation, but seems to amplify the crawls and rainbows more than the actual picture. if you find one of these, turn it off and DeDot might have a better chance.hmmm, saturation settings, eh? I'll definetly try playing around with that tonight when I get home. That would be great if tweaking a simple setting like that could fix this whole problem, or at least minimize it a bit.

[HyperSpad]

Originally Posted by neuron2
Please read and follow forum rules, specifically, rule 12: Do not ask what's best. Thank you.Sorry...I just reworded my question. How's that?

[Guest]

Sorry...I just reworded my question. How's that? Perfect. Thank you very much.

If you can arrange to capture from S-Video rather than composite, you'll eliminate the problem at its source. Don't you have an S-Video or component output?

[HyperSpad]

Would it be worth it to buy a VCR with s-video out that I could first run my analog cable through, and then hook the s-video out up to my capture card?

Do VCRs have comb filters like TVs do?

[Guest]

Would it be worth it to buy a VCR with s-video out that I could first run my analog cable through, and then hook the s-video out up to my capture card? Probably not. Capturing S-Video is most useful when you have a source signal that is not composite, such as digital cable, satellite, DVD player, etc.

If the VCR receives composite and outputs S-Video, then yes, it must have a comb filter. I would doubt that it is better than the one in a quality TV, however, but I couldn't rule it out. It might be better than the one in a cheap capture card; you'd have to try it to see.

[Inc]

I do use an external s-video output capable VCR as tunerdevice. The Quality is better then the served signal via the SAA7134 Cards internal Tuner. As its an external device its less sensible to the PCs internal things which could cause an affecting of the cards tuner output. But the dotcrawl sometimes is still present as the signal from the analog CableTv Provider for shure is not served as separate y/c signal as also neuron2 mentioned.