Abstract: Combining spatial layered coding with fine granularity scalability coding techniques, an algorithm of spatial fine granularity scalable coding (S-FGS) is proposed. It provides high adaptability to network bandwidth, does not reduce the compression ratio and retains quality of reconstructed images. Based on this algorithm, a coding system model is proposed for still image data compression. Experimental results show that the time complexity of the algorithm is mainly affected by scalable granularity, and the algorithm is viable with specific granularity setting.