Histogram equalization Compute the gray level (luminance) histogram for an image and equalize it so that the tones look better (and the image is less sensitive to exposure settings). You may want to use the following steps: 1. Convert the color image to luminance (Section 3.1.2). 2. Compute the histogram, the cumulative distribution, and the compensation transfer function (Section 3.1.4). 3. (Optional) Try to increase the "punch" in the image by ensuring that a certain fraction of pixels (say, 5