Extrema points coding based on empirical mode decomposition: An improved image sub-band coding method

The extrema points coding approach is an attractive way to represent the image. This approach will potentially become a new scheme to compress the still image and will make a great progress for mobile visual search technique. According to the idea of extrema points coding, a complete image compression approach is presented in this paper. Based on the Empirical Mode Decomposition (EMD) theory, digital image is decomposed into different sub-bands, where the most important extrema points are extracted. On mid and low frequency sub-bands, a novel compression method with obvious advantages over current methods is brought out. Combined this method with Linderhed’s “coding of the EMD using DCT of variable sampled blocks (VSDCTEMD)”, a complete digital image compression scheme is designed. It improves Linderhed’s image compression scheme based on EMD.

► Design a complete extrema points coding scheme at different sub-bands and give a new choice to compress the still image.
► Solve the problem of position coding for extrema points.
► Design an effective method for the initial step of high-speed mobile visual search.