Border width could be individually selected for each side within Border Size selector. If sync box (next to the selector) is checked, then the width assigned to any border side, would automatically be inherited by the 3 remaining sides. Otherwise, if sync box is unchecked border width is assigned independently for each side of the main image.
Border coloring is done by assigning a certain gradient type with 4 transitional color points + center and hatch color.
All sample border display images were create with a plain yellow image surrounded by a thick 20 px. border with bright colors as they have assigned on a configuration displayed below:

There are 4 types of the border could be created (gradient configuration vise).
Gradient none
Classic Border. Gradient points 1-4 render respectively: top, right, bottom and left border. |
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Gradient Blend Corners
Similar to none. Gradient points 1-4 render respectively: top, right, bottom and left border. Corners however are blended. |
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In addition the center color is used to blend from center to sides. Although in the most of the cases this type of blending is masked by the main image, it does set the shade for all 4 border colors. Darker center color creates darker border shade.
Here is the same image with fully transparent main gradient so that border image is completely revealed.
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Gradient Angle
Gradient Shape Burst
Color points 1-4 are used to render gradient across all 4 sides of border image in respect to the image shape- from side to the center. |
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Center color is used to blend color point 4 with the center of the border image. Although in the most of the cases this type of blending is masked by the main image, in certain cases (when border width is different for each side) it would partially be revealed. Here is the same image with fully transparent main gradient so that border image is completely revealed. |
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