1. A method comprising: obtaining, by a computing device, an input image, wherein the input image has a white point represented by chrominance values that define white color in the input image; based on colors of the input image, generating, by the computing device, a two-dimensional chrominance histogram of the input image; convolving, by the computing device, the two-dimensional chrominance histogram with a filter to create a two-dimensional heat map, wherein entries in the two-dimensional heat map represent respective estimates of how close respective tints corresponding to the respective entries are to the white point of the input image; selecting, by the computing device, an entry in the two-dimensional heat map that represents a particular value that is within a threshold of a maximum value in the heat map; and based on the selected entry, tinting, by the computing device, the input image to form an output image.