Detect image without curves

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ethaniel
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Detect image without curves

Post by ethaniel » 2019-04-12T20:45:32-07:00

Dear IM community, I've been banging my head against a wall for 6 months now.
I have a live beach camera which sometimes loses it's signal and produces a still image (which has no curves):
Image

This is a example of a good image:
Image

Is there non-expensive computing wise way of detecting the first image? (the camera is connected to a udoo board, which can barely pull the broadcast of the stream). The problem is that it always contains different colours (but the shape stays pretty much the same).

I am thinking that a good approach would be to count the number of curves in the image (but couldn't figure a way how to do it).

snibgo
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Re: Detect image without curves

Post by snibgo » 2019-04-13T02:17:43-07:00

How often is an image captured? A good method might be to compare adjacent frames: if they are similar, they are both good, but if they are very different then at least one is bad.
snibgo's IM pages: im.snibgo.com

ethaniel
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Re: Detect image without curves

Post by ethaniel » 2019-04-13T04:18:13-07:00

I tried comparing 2 frames, but sometimes there are variations in 2 "bad" frames which are higher than variations in 2 "good" night frames. So it's not a 100% optimal solution.

snibgo
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Re: Detect image without curves

Post by snibgo » 2019-04-13T07:22:22-07:00

That's what we want. A small difference between two good adjacent frames, and a large difference between one good and one bad, or two bad frames.

If two adjacent bad frames have a small difference, then the test needs to be more complex.
snibgo's IM pages: im.snibgo.com

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