1. A method for image processing, the method comprising: receiving first and second pattern exemplars and a blend map for merging the first and second pattern exemplars; and utilizing a correspondence search process, including a parallel coherent random walk search, to determine first and second target images for use in producing a composite image, the first and second target images corresponding respectively to the first and second pattern exemplars; wherein a constraint imposed on the correspondence search process is based on the blend map for merging the first and second pattern exemplars.