Using Fixed-Point DSP Implementation Method of LS9/7 to Improve the Performance of JPEG2000

JPEG2000 is the state-of-the-art image compression standard which has many attractive features. However, the lifting coefficients of CDF9/7 used in JPEG2000 are a group of irrational numbers. It will result in complex computation and vast storage if we directly use CDF9/7 in lifting algorithm. Therefore, CDF9/7 needs to be implemented in fixed-point method. The existed fixed-point implementation methods of CDF9/7 can solve the problem of computation and storage, but they make the quality of reconstructed image degrade. To solve this problem, we use the fixed-point implementation method of LS9/7, which adopts the post-scaling method, to improve the performance of JPEG2000 in this paper. Compared with the two fixed-point implementation methods of CDF9/7, the computation complexity of the proposed method has been decreased by 34% and 28.3% while the quality of reconstructed image has been improved by more than 3 db. Its performance is very close to the float-point implementation of CDF9/7.