摘要
针对ＪＰＥＧ在高压缩比情况下，解压图象的质量较差，近年来提出了不少改进算法。ＤＣＴ的零树编码（ＥＺＤＣＴ）［１，２］是效果最好的算法之一，但其仍无法克服基于ＤＣＴ的算法所固有的缺点——方块效应。此文提出一种层式ＤＣＴ的零树图象编码方法（ＥＺＬＤＣＴ），与ＥＺＤＣＴ相比，能较好地消除方块效应；并且对复杂的图象（如“Ｂａｒｂａｒａ”，“Ｇｏｌｄｈｉｌ”等），在相同压缩比的情况下有更高的ＰＳＮＲ值。
Since JPEG does not perform well at high compression ratio, many algorithms have been proposed recently to get better performance. One of the best is EZDCT . But it still can not overcome the inherent wackiness of DCT based algorithm— blocking artifacts. In order to solve the problem, an algorithm, namely the embedded zerotree for layered DCT(EZLDCT) is proposed in this paper. Compared with EZDCT, it can reduce blocking artifacts efficiently and gain better image quality for complex images, such as 'Barbara' and 'Goldhill' etc., at the same compression ratio.
出处
《中国图象图形学报（A辑）》
CSCD
1998年第3期225-229,共5页
Journal of Image and Graphics
