Region correspondence for image matching via EMD flow

The content of an image can be summarized by a set of homogeneous regions in an appropriate feature space. When exact shape is not important, the regions can be represented by simple "blobs". Even for similar images, the blobs in the two images might vary in shape, position, and the represented features. In addition, separate blobs in one image might get merged together in the other image. We present a novel method to compute the dissimilarity of two sets of blobs. Gaussian mixture modeling is used to represent the input images. The Earth Mover's Distance (EMD) is utilized to compute both the dissimilarity of the images and the flow matrix of the blobs between the images. The flow is used to merge blobs such that the dissimilarity between the images gets smaller. Examples are shown on synthetic and natural images.