Ways to sparse representation: An overview

Many algorithms have been proposed to find sparse representations over redundant dictionaries or transforms. This paper gives an overview of these algorithms by classifying them into three categories: greedy pursuit algorithms, l _p norm regularization based algorithms, and iterative shrinkage algorithms. We summarize their pros and cons as well as their connections. Based on recent evidence, we conclude that the algorithms of the three categories share the same root: l _p norm regularized inverse problem. Finally, several topics that deserve further investigation are also discussed. Supported by the Joint Research Fund for Overseas Chinese Young Scholars of the National Natural Science Foundation of China (Grant No. 60528004) and the Key Project of the National Natural Science Foundation of China (Grant No. 60528004)