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Sampling device

jasonben

Jul 15, 2009
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cradlemess’s post about a camera got me to thinking. I’ve heard of sampling methods before – and how they can be random or organized in different ways. Is there a time-lapse photography method that involves sampling different areas in a field of vision at different time intervals – perhaps to save memory? What would an algorithm used by such a camera consider?
 

Resqueline

Jul 31, 2009
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Some video compression algorithms (mpeg4?) does just that; record one full scene, and then just the movements (the pixels that are changing state) for a while. This limits the bandwidth needed for transmission. You can sometimes see the effect of a too narrow bandwidth (or too high compression) when there's a lot of movement filling the picture (like rushing water). Then there appears square blocks similar to what you see when you try to save a jpg picture with too high compression.
 

jasonben

Jul 15, 2009
22
Joined
Jul 15, 2009
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Some video compression algorithms (mpeg4?) does just that; record one full scene, and then just the movements (the pixels that are changing state) for a while. This limits the bandwidth needed for transmission. You can sometimes see the effect of a too narrow bandwidth (or too high compression) when there's a lot of movement filling the picture (like rushing water). Then there appears square blocks similar to what you see when you try to save a jpg picture with too high compression.

So that algorithm is based on some kind of rate of change of groups of data that are spacially coordinated. I just looked up memory on the computer. It was related to how information - which could be images, was categorized, how distinct it was, how much energy was required to capture the image, and how much the information - which could be an image, was related to its environment. Or, something like that. I had looked up the extrastriate cortex - and learned that there were many ways of categorizing visual data. I imagine that there is equipment that utilizes algorithms related to all of these concepts, and relations of these concepts to time - such as how long occurrence lasts. However, the possibilities still aren't clear to me. I was wondering what related algorithms consider.
 
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