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Discussion Starter #1
I Have recently started de-interlacing tests, and I'm not sure what/how much to expect from DScaler. From comparisons to a Farouja 3000, they really appear to be quite close in general, however with a very cheap tuner card and S-Video, I notice a lot of 'shimmering' with white text on dark backgrounds. In greedy 2 I still see interlacing artifacts on fast motion, like someone's arm swinging.


Can a cheap capture card cause this? Have I mis-configured DScaler somehow, or is this acceptable performance considering how bad interlaced broadcast video really is?


Duron 700

ABit KT7

Geforce2 MX

256 MB

STB (cheap Tuner) capture card

Win 98 SE


Thanks for any insight,

Oz
 

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Doing movie deinterlacing is easier than video. Thus with a movie, DScaler or Faroudja will do the same. The difference will be seen on stability and, of course, quality of the a/d stage. That's where grab cards often suck.


With video deinterlacing, you can experience bad a/d conversion, but also deinterlacing artefacts.


So perhaps start your deinterlacing tests with movies, where you can be quite confident that any bad things you see is only related to the capture card.


If you want to see quite high quality grabs, see Ken's recent ones of the 5th element http://www.avsforum.com/avs-vb/showt...threadid=87743


Really the kind of thing that makes you say "yes, scaling an external source is possible"
 

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If you see motion artifacts using Greedy (High Motion) they are probably not a result of your capture card. They are more likely a result either of dropped frames or of switching in and out of Auto Pulldown mode.


On a Duron 700 you should probably not be using any of the advanced options in the Greedy/HM control panel. All the check boxes should be turned off.


Then, depending upon your test material, you can turn DScaler's regular Auto Pulldown on or off, to try to isolate the problem. Watching a movie you would expect to have it turned on. However if you keep the status bar visible you can see when it changes pulldown methods or rapidly goes into or out of pulldown mode. If it does this too often for a given source then you may want to turn it off.


When watching video source you might want to turn Auto Pulldown off. If there is still jerky video or dropped frames then you can try lowering your pixel width to 640.


At this point even with video source on your machine there should be very few motion artifacts. But remember that video deinterlacing is often a tradeoff between detail and blemishes. If you really have to you can go into the Greedy/HM control panel, click Advanced, and (very slightly) lower the Motion Threshold or (very slightly) increase the Motion Sensitivity sliders. If you get it hosed up then just click the Defaults button.


Doing this can decrease any remaining motion artifacts but if you overdo it there may be a loss of detail, jagginess on diagonal lines, or even increased jitter at higher levels.


Remember that it is possible to have multiple named profiles, so if you wanted to have one customized for, say, watching basketball video with high motion, it is possible to do this.


Good luck,


- Tom
 

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Try setting sleepinterval=0 in your dscaler.ini file. That helps some people with frame drops, including myself. Text shimmers for me when I'm dropping frames.
 

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Discussion Starter #5
Thanks everyone for the info. I'll be spending the weekend doing tweaks as you all have suggested. I'll certainly report back on interesting findings that may help others too.


I didn't' realize that a Duron 700 might not quite keep up for DScaler. I was running relatively high too... 1024x768. Maybe I'll drop a 1.0GHz athalon chip in, if it is determined to be a lot of processing issues.


Oz
 
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