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Capture quality? (Read 897 times)
mark hill
Capture quality?
Aug 16th, 2005, 10:01am  
I'm using a fairly standard, but not too new video camera to capture. The cameras main feature is a decent lens and optical zoom.

I need to capture for reproduction purposes. Does anyone know what the limits are?

Grabbing for 300dpi means setting things really big. If I want a 50cm image it means I've got a video size of 5900, 5900 which kills the cpu and prevents me from doing anything with it. (plus 5900 is probably nonsense in terms of what's available from the camera)

Does anyone have any suggestions, or know what the basic guidelines are for video capture and print?


*** UPDATE ***

How does rendering from pre-recorded film differ from direct capture in terms of what's available?

*** Further Update ***

After experimenting I'm beginning to suspect that capture resolution reaches its maximum at around 640*480 - due to capture cards and DV encoding for firewire transfer. Anything after that is just doubling up, making fatter files and slowing things down.

I'm still not 100% that I'm straight on all this, so any pointers would be appreciated, as the best print quality with the above resolution gives an image probably around 5cm high, and I was hoping for much more!
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« Last Edit: Aug 16th, 2005, 2:07pm by mark hill »  
 
fry
Re: Capture quality?
Reply #1 - Aug 16th, 2005, 2:45pm  
couple things..

- your camera is probably limited to somewhere around 640x480. if it's a dv camera, it might be dv size which i think might be something like 720x480. this would likely be somewhere in your camera specs (perhaps a "technical info" page at the end of the manual?)

- if you're on windows and using winvdig, you might be limited even further, as winvdig uses older msft video apis which were formerly limited to 320x240, but i haven't verified this for a while. if you're on a mac, you should be able to get as high res as what you're being sent by the camera.

- as for using a pre-recorded file (i think that's what you mean?) you'd be better off going that route if possible. processing simply isn't built for real-time rendering of large video. so if you just want to write a sketch to operate on a file and render that back out as frames, then you'd be in better shape doing that from a saved .mov file.
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mark hill
Re: Capture quality?
Reply #2 - Aug 16th, 2005, 3:14pm  

I'm on a mac and seem to be getting the full wack.

I've got the rendering side of things squared away, now that I'm not capturing duplicate info to a huge buffer.

Thanks Ben.

What do folk usually do, when they want to make high-quality prints from video? Dedicated capture cards etc.?
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