Thank you. I've tested both img files. Suppose you want to clip the image, you just need to do
instead of image(MM). Because image requires color matrix data, but your img file is a grayscale image.
I'm not sure what is the root cause of this issue without an actual img file, but you're using R2020b you can use readgeoraster function for ERDAS IMAGIN file (.img). Mapping Toolbox is requred, but it's more easier.
Instead of using imageload, how about using readgeoraster?
I = readgeoraster('D:\regionGrowing_MLT\TM570007_LML_08_06.img');