A wavelet coding method based on low memory and block bit-length

A wavelet coding method based on memory optimization and block bit-length is expressed in this passage. The memory occupancy can be reduced through three measures adopted in the arithmetic in the process of coding and coding efficiency can be increasingly improved, respectively. The three measures mentioned above are: (1) define bit-length and establish block bit-length chart in terms of block maximal absolute value to substitute for lists in the process of delicating and ranking, so memory space can be saved; (2) the output of bit-length chart is in terms of bit-length difference and is provided for the decoding process; (3) swift search according to bit-length chart and overcome repeat 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 PSNR.