Fix bugs in Sobel operator and Canny's nonMaxSuppression #2600
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The gradient computation equations where flipped earlier which is fixed now. Also, modified the sobel to use same border management as OpenCV. Any pixel accessed outside the borders is reflected across the border now. The test data has also been updated accordingly.
Fix gradient factor equation in canny nonmaxsuppression. In the case of negative gradients along both x and y directions, the interpolation factor was incorrectly being calculated. Apart from this, sobel derivaties respective sobel masks were flipped along edge direction (not a transpose, but flip along axes). Terrible bug introduced by me and fixed now in f5e4e0e
umar456
approved these changes
Jul 27, 2019
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Resolves #2588
@greennbeans , thank you!
Fix gradient factor equation in canny nonmaxsuppression. In the case of negative gradients along both x and y directions, the interpolation factor was incorrectly being calculated.
Apart from this, sobel derivaties respective sobel masks were flipped along edge direction (not a transpose, but flip along axes). Terrible bug introduced by me and fixed now in 5e5c022
Requires arrayfire/arrayfire-data#15