In order to achieve the desired task of separating foreground from the background of the provided images, consider using 'Image Segmenter' app. Refer to this MathWorks documentation to know about the 'Image Segmenter' app:
Also, consider using this File Exchange tutorial provided by @Image Analyst: https://www.mathworks.com/matlabcentral/fileexchange/25157-image-segmentation-tutorial?s_tid=srchtitle
Another approach which can be used in this case could be to use 'grabcut' function which extracts the region of interest from the image as defined by the user. Follow the example given in this MathWorks documentation to know more about this:
Hope this helps! Thanks.
