Fix clipping bug in SQDIFF_NORMED template matching

[danielenricocahall]

Addresses #15215 regarding CV_TM_SQDIFF_NORMED clipping at 1.0, despite the range being > 1. The test case is the example presented in the ticket.

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[danielenricocahall]

Hi @vpisarev! I'm having some trouble addressing the last few failing tests for the CL builds + Mac build. They all seem to be the same, and I can't replicate locally. It looks like the norm is still being clipped at 1 when the difference is computed - do you have any thoughts/suggestions?

[asmorkalov]

There is OpenCL implementation of MatchTemplate that follows the original function logic: https://github.com/opencv/opencv/blob/3.4/modules/imgproc/src/opencl/match_template.cl

[danielenricocahall]

There is OpenCL implementation of MatchTemplate that follows the original function logic: https://github.com/opencv/opencv/blob/3.4/modules/imgproc/src/opencl/match_template.cl

@asmorkalov yes I saw that - I made changes to the function in that file to match the new logic, but it doesn't appear to be addressing the issue. With SQDIFF Normed, we should just be taking the numerator and the denominator with no conditionals.

[asmorkalov]

@alalek I created PR opencv/opencv_extra#916 for sanity check update. Please take a look.

[alalek]

@asmorkalov Public CI is not able to collect patches from different users (not implemented because it is unusual case)

[asmorkalov]

Replacement: #20770