1. A computer-implemented method, comprising: obtaining a plurality of images of a scene, wherein one of the images is a base image and a different one of the images is a source image; obtaining input indicating a stroke applied to the source image, wherein the stroke specifies a set of pixels in the source image; identifying a region of the source image from the stroke, wherein the region comprises a plurality of contiguous pixels in the source image, and wherein said identifying a region comprises determining that each of the plurality of pixels in the region is similar to the pixels in the set of pixels specified by the stroke according to one or more characteristics of the pixels; blending the pixels from the region of the source image with pixels in a corresponding region of the base image to generate a blended image; performing iteratively said obtaining input indicating a stroke, said identifying a region of the source image from the stroke, and said blending the pixels for a plurality of different strokes identifying a plurality of regions from the plurality of images of the scene, wherein each performance updates mapping information that maps pixels in the blended image to one or more of the plurality of regions used to blend each respective pixel; and in response to input modifying a blending level used to blend at least one of the plurality of regions, blending pixels from the plurality of images with the corresponding pixels of the base image to generate a new blended image based on the mapping information and according to the modified blending level.