Choosing neighbours, window, matrix size in GLCM
Hello, I'm going to implement GLCM to retrieve texture features of leaves. I've already read about algorithm and it is clear to me, but I don't know:
1) How to choose the best offset of neighbours(distance and direction)?
In one text I've read that too large glcm matrix may give worse results if image has less gray levels(many zeroes in matrix). Author gives advice to rescale data to 4 bit.
2) Is it worth to do that? Will image not lost many information?
2a) Can I do rescaling in opencv with some built-in function?
Despite of above, I intended to take gray scale image and calculate GLCM on entire image, but there is also a concept of window not clear for me, so:
3) How the algoritm will lool like with using window of particular size?
Please take into account tha performance is important to me, because this will be used in android app.
4) Is there anything else important about GLCM on what should I pay attention?
Thanks in advance.