Smooth chroma quantization curve for Daala

This video is a before and after comparison of continuously varying the chroma quantization offset on still images from the subset1 corpus. The curve has been fitted to minimize the mean of perpixel CIEDE2000 color distance. A tightly fitted curve was found by global optimization and relaxed to a simple function of similar shape. Daala is the codename for a new video compression technology. The effort is a collaboration between Mozilla Foundation, Foundation and other contributors.