Huang Yong-Huai, Chung Kuo-Liang
Department of Computer Science and Information Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan 10672, ROC.
IEEE Trans Image Process. 2007 May;16(5):1258-68. doi: 10.1109/tip.2007.894227.
Recently, several efficient context-based arithmetic coding algorithms have been developed successfully for lossless compression of error-diffused images. In this paper, we first present a novel block- and texture-based approach to train the multiple-template according to the most representative texture features. Based on the trained multiple template, we next present an efficient texture- and multiple-template-based (TM-based) algorithm for lossless compression of error-diffused images. In our proposed TM-based algorithm, the input image is divided into many blocks and for each block, the best template is adaptively selected from the multiple-template based on the texture feature of that block. Under 20 testing error-diffused images and the personal computer with Intel Celeron 2.8-GHz CPU, experimental results demonstrate that with a little encoding time degradation, 0.365 s (0.901 s) on average, the compression improvement ratio of our proposed TM-based algorithm over the joint bilevel image group (JBIG) standard [over the previous block arithmetic coding for image compression (BACIC) algorithm proposed by Reavy and Boncelet is 24%] (19.4%). Under the same condition, the compression improvement ratio of our proposed algorithm over the previous algorithm by Lee and Park is 17.6% and still only has a little encoding time degradation (0.775 s on average). In addition, the encoding time required in the previous free tree-based algorithm is 109.131 s on average while our proposed algorithm takes 0.995 s; the average compression ratio of our proposed TM-based algorithm, 1.60, is quite competitive to that of the free tree-based algorithm, 1.62.
最近,已经成功开发了几种高效的基于上下文的算术编码算法,用于对误差扩散图像进行无损压缩。在本文中,我们首先提出一种新颖的基于块和纹理的方法,根据最具代表性的纹理特征来训练多个模板。基于训练好的多个模板,我们接下来提出一种高效的基于纹理和多模板(TM)的算法,用于对误差扩散图像进行无损压缩。在我们提出的基于TM的算法中,输入图像被划分为许多块,对于每个块,根据该块的纹理特征从多个模板中自适应地选择最佳模板。在20幅测试误差扩散图像以及配备英特尔赛扬2.8 GHz CPU的个人计算机上,实验结果表明,在编码时间略有下降的情况下,平均为0.365秒(0.901秒),我们提出的基于TM的算法相对于联合二值图像组(JBIG)标准[相对于Reavy和Boncelet提出的先前用于图像压缩的块算术编码(BACIC)算法]的压缩改进率为24%(19.4%)。在相同条件下,我们提出的算法相对于Lee和Park先前算法的压缩改进率为17.6%,并且编码时间仍然只有少量下降(平均0.775秒)。此外,先前基于自由树的算法平均所需的编码时间为109.131秒,而我们提出的算法需要0.995秒;我们提出的基于TM的算法的平均压缩率为1.60,与基于自由树的算法的1.62相比具有相当的竞争力。