Image coding using concentration and dilution based on seam carving with hierarchical search

Image concentration is an image resizing technique which shrinks an image size but does not change important region(s) in the original image, whereas image dilution is the reverse process to image concentration. In this paper, we incorporate image concentration/dilution process in image coding. An image retargeting method called seam carving is used for image concentration. Furthermore, it is modified to yield rate-distortion optimized seams by a hierarchical search process. Our method can be incorporated into any image encoder since the image concentration (dilution) is a pre(post)- processing of image encoder (decoder). In the experimental results, JPEG/SPIHT with image concentration/dilution presents significant bitrate savings compared with the original JPEG/SPIHT alone and reconstructed image qualities are very similar to each other.