Convert all pixels of one color to another in JAVA

edit

then you invert (the color of) your Mask by:

Core.subtract(new Scalar(255), mask, mask); // mask = 255 - mask;

and again use setTo() with the inverted mask, and another color.

In the inrange function if we have an image which has various shades of brown then how can we decide the lower bound and upper bound?

maybe convert to HSV first, and look mainly at Hue (careful: [0..180] range in opencv)

Can you please show by an example on how to select a range of color like shades of brown/black as even in HSV its having 3 parameters and in an image there are many shades of the same color, so how will the range be decided with one being lower and other being higher.

sorry, i do not have java here.

Right now what I am doing is I took an average color of brown from the image, saw the RGB value and then for lower index I am subtracting 20 and for higher I am adding 20 from all RGB. It does give shape in some form. If my approach is wrong then please inform me.