摘要
JPEG2000压缩算法在卫星遥感图像压缩领域有着广阔的应用前景,但由于JPEG2000中的CDF9/7小波提升系数是一组无理数,其直接用于提升算法存在计算复杂度高、存储量急剧增加的问题,因此,需要对其进行定点实现。CDF9/7定点实现方法虽可以解决上述问题,但存在恢复图像质量下降的缺点。为了解决这一矛盾,在构造LS9/7小波的基础上,结合后拉伸算法,提出了一种LS9/7小波定点实现方法。与CDF9/7的两种定点实现方法相比,其计算复杂度分别降低了34%和28.3%,而恢复图像的质量(信噪比)却提高了3dB以上,与CDF9/7浮点实现方法的性能相当。
JPEG2000 compression algorithm has broad applications in the field of satellite remote image compression. However, the lifting coefficients of CDF9/7 are a group of irrational numbers, which result in complex computation and require vast storage directly used in lifting algorithm, plus a fixed-point method is needed. The existed fixed-point implementation methods of CDF9/ 7 can solve the problem of computation and storage, but they degrade the quality of the reconstructed image. In order to solve this problem, a fixed-point implementation method of LS9/7, based on constructing LS9/7 wavelet bases and adopting postscaling method, is proposed in this paper. Compared with two fixed-point implementation methods of CDF9/7, the complexity of computation has been decreased by 34% and 28.3% and the quality of reconstructed image has been improved by more than 3db. Its performance is very close to the float-point implementation of CDF9/7.
出处
《中国图象图形学报》
CSCD
北大核心
2008年第10期1833-1836,共4页
Journal of Image and Graphics
基金
国家863项目(2006AA701121)
