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I will try to explain my problem in few words. I have an image representing a person. Thanks to my code I manage to compute the background subtraction and have the resulting shape of the person in HSV color space. Unfortunately, I have some noise (as you can see in the image below) and I should properly choose the HSV values in order to minimize them.

What I should do (according to my professor) is:

"Mark in Photoshop what the foreground for the image should be and calculate how far you’re off with specific settings".

Now, I can try to figure out how to extract the shape of the body and reconstruct what the final image should be. But I am definitely not able to compute this "distance" between what the image should be and the image that I am provided in order to find the HSV parameters.

Any suggestion?

Thank you in advance!


share|improve this question
There's a good question in here, but I'm not sure if this is suitable for this stackexchange. Maybe better at (if this is a frame of a video) or (if this is just a photo). I flagged this for moderator attention so it can be moved. Furthermore it is not clear to me what you mean by the sentence But I am definitely not able.... Can you explain that by making and edit? – Saaru Lindestøkke Dec 9 '13 at 17:09
It means that I just do not know how to compute that distance in a way to find those parameters that I need. I am sorry if this is not the right place for the question! – Enrico Ribelli Dec 9 '13 at 20:39
It's also unclear to me why you use HSV values to reduce the noise and how distance relates to HSV values. – Saaru Lindestøkke Dec 9 '13 at 21:16
It is not my decision. I just have to decide properly which values of HSV I have to use to reduce the noise. I still don't know how photoshop can be useful to determine them. So I asked my professor to explain me better how to find these values and he answered me exactly what you see above in quotes. It seems that I should get the ideal shape of the body without any kind of noise. Put it in a black background in order to reproduce the ideal image. Compute the distance between it and the image with noises and find out with any photoshop function which are the best values for my HSV filter. – Enrico Ribelli Dec 9 '13 at 21:55
I finally understand what you mean by distance. You mean the difference, right? In that case open the source image in Photoshop, select the person standing with any tool of your liking (e.g. lasso tool), copy and paste the selection on a black background, add a color overlay such that the selected area is white and show this image side-by-side with the result from your code. You could also quantify the difference by comparing the two images programmatically. Your prof. just wants that you have a baseline to which you can compare your code. – Saaru Lindestøkke Dec 9 '13 at 22:07

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