compressed adj. 1.压缩过的;(文字)简练的。 2.【植物;植物学】(左右)扁平的;【动物;动物学】侧扁的,宽度大于长度的。 compressed air 压缩空气。 compressed wallboard 压扁壁板。
image n. 1.像,肖像,画像;偶像。 2.影像,图像。 3.相像的人(或物);翻版。 4.形像,典型。 5.形像化的描绘。 6.【语言学】形像化的比喻,象喻。 7.【心理学】概念,意象;心象。 graven image 雕像。 image frequency 图像频(率);镜频。 real image 【物理学】实像。 television image 电视像。 virtual image 【物理学】虚像。 God's image 人体。 He is the image of his father. 他活像他父亲。 the spitting image of 同…完全一样的人[物]。 speak in images 用比喻讲;说话形像化。 thinking in terms of images 形像思维。 vt. 1.作…的像,使…成像。 2.反映。 3.想像。 4.形像地描画;用比喻描写。 5.象征。 adj. -less 缺少形象的。
Furthermore i introduce the elementary wavelet theory . secondly , two classical wavelet image coding algorithm based wavelet zerotree idea are introduced and two improved algorithms are proposed . the first algorithm is that we combine runlength coding and zerotree coding in which ll band coefficients are coded lonely with dpcm . the second algorithm is the zerotree algorithm with vector quantization is combined with ll band coefficients alone coding with dpcm . the simulating results show they can get better performance both in psnr and subjective quality . thirdly , we make research on how to compress image combined with deleting noise by zerotree algorithm . first we use soft - threshold method to denoise image with noise , and then the first improved zerotree algorithm is used to compress image . simulating results show that the subjective quality of the decoded image is good . lastly , we compare , analyse and summarize all kinds of compress ing methods based on wavelet zerotree idea 本文提出了两种改进算法,算法一: dpcm 、零树和游程相结合的改进算法;算法二: dpcm 、零树和矢量量化相结合的改进算法;仿真结果表明这两种改进算法无论从客观信噪比还是从主观质量都取得了很好的效果,从而证明改进方案是有实际意义的;然后是含噪图像的小波零树编码去噪研究,软门限去噪以后采用第一种改进算法对图像进一步压缩,解压后的仿真结果显示噪声得到了很好的去除;最后是对基于零树编码思想的各种编码方法进行总结、分析和比较。