How to remove floating background?
I have images with a black figure on white background, but the brightness of the latter varies smoothly in different parts.
How to make it uniform or max. white (255)? Threshold cut is not possible because at the corners brightness drops almost to the brightness of the figure.
I think you can try the answers given here
The second method looks better because it doesn't require parameters like object's size. Any hints what it does? So far as I understand, there is no source image here. Only the background produced from it and the difference. Right?
Method 2 is fit background with a quadric. Image can be thresholded and only white pixel can be fit