Takes a set of images and variably-shaped ROI masks, extracts the masked regions into rectangular tiles, and assembles into one image. Useful for visualizing training examples that come from lots of images.
Python 3.5+
pillow - Python Imaging Library
scikit-image
rectpack - 2D-bin packing library. Obtain via pip install rectpack, or from https://github.com/secnot/rectpack/ .
Extract the tiles from each of your images and masks.
tiles = extracttiles(img1, mask1, 5)
tiles.extend(extracttiles(img2, mask2, 5))
Then call layouttiles to arrange the tiles into a nice mosaic using 2D bin packing.
mosaic = layouttiles(tiles)