Histogram comparison

One interesting functionality offered by OpenCV in connection with histograms is the cv2.compareHist() function, which can be used to get a numerical parameter expressing how well two histograms match each other. In this sense, as histograms reflect the intensity distributions of the pixel values in the image, this function can be used to compare images. As previously commented, the histograms show only statistical information and not the location of pixels. Therefore, a common approach for image comparison is to divide the image into a certain number of regions (commonly with the same size), calculate the histogram for each region, and, finally, concatenate all the histograms to create the feature representation of the image. In this example, for simplicity, we are not going to divide the image into a certain number of regions, so only one region (the full...