1. A method, comprising: segmenting a head image from a source image based on a model of the source image as a mixture of at least two image layers, wherein one or more of the image layers are components of a foreground corresponding to the source head image and one or more other ones of the image layers are components of a background corresponding to parts of the source image outside the source head image; color-adjusting the source head image based on skin regions of a target head image in a target image; geometrically transforming the color-adjusted source head image to conform to the target head image in pose and size; and generating a composite image, wherein the generating comprises compositing the geometrically transformed and color-adjusted source head image into a version of the target image at a location corresponding to the target head image.