An Improved STC Image Compression Method

In this paper, inspired by the idea of the S-Tree Coding (STC), we propose an improved STC image compression method by using the Nonoverlapping Non-symmetry and Anti-packing Model (NNAM) and the extended shading approach, which is called the NNAM Coding (NNAMC) method. In our method, the encoding can be performed in O(n log n) time and the decoding can be performed in O(n) time, where n denotes the number of pixels in a gray image. By comparing our proposed NNAMC method with the conventional STC method, the experimental results presented in this paper show that the former can significantly reduce the lower bit rate and the number of homogenous blocks than the latter whereas remaining the satisfactory image quality.