关键词: 稀疏表示, 图像压缩, K-SVD算法, 小波变换

Abstract: The sparse representation based on over-complete dictionary is a new image representation theory. The redundancy of over-complete dictionary can make it effectively capture the geometrical characteristics of the images. SAR image compression is achieved based on over-complete dictionary sparse representation. Only the sparse decomposition coefficients and the index are needed to be stored in order to seize the image’s information. A learning method—K-SVD is adopted to design the dictionary. Because the training examples are all from the image itself, the dictionary should be more approximate to the image’s structure. The simulation implies the proposed method is useful for SAR image compression and it outperforms the DCT based Jpeg method and the wavelet based EZW and SPIHT method.

Key words: sparse representation, image compression, K-SVD algorithm, wavelet transform