An Embedded and Efficient Low Memory Hierarchical Image Coder

An embedded and efficient low memory hierarchical image coder is expressed in this passage. The memory occupancy can be reduced through four measures adopted in the arithmetic in the process of coding and coding efficiency can be increasingly improved, respectively. The four measures mentioned above are: (1) adopt a large quantized interval (2) define bit-length and establish block bit-length chart in terms of block maximal absolute value to substitute for lists in the process of fining and ranking, so memory space can be saved; (3) output bit-length chart in terms of bit-length difference and limit code current; (4) swift search according to bit-length chart and overcome repeating scan. The experimental results showed that: the arithmetic can reduce memory occupancy in the process of coding and increase the coding speed effectively, meanwhile, it can keep the high quality of SNR. It has great significance in hardware design for wavelet coding.