Pixel blocks of a user-generated print job raster page are clustered into raster color clusters, and pixel blocks of a corresponding scanned page are clustered into scanned color clusters. For each raster color cluster, if a color difference between the cluster and a corresponding scanned color cluster is greater than a threshold, color fading of the cluster is determined from simulated depletion of each colorant of a printing device, and a likely depleted colorant is determined based on the corresponding scanned color cluster and the determined color fading. A most likely depleted colorant is determined from the likely depleted colorant predicted for each raster color cluster for which the determined color difference is greater than the threshold.