The image compression standard in pacs now is the jpeg standard based on the dct ( discrete cosine transform ) algorithm , which can only be applied in the limited areas 目前在pacs系统中较多采用的是jpeg图像压缩标准，该标准采用以离散余弦变换算法为主的区块编码方式,但有一定的局限性。
The system is composed with six sections which are entropy decoder , inverse z transform , inverse quantization , inverse discrete cosine transform ( idct ) , up sampling and color space transform Jpeg解码算法主要由熵解码、逆z变换、反量化、反离散余弦变换、内插和色度空间转换六部分组成。
Abstract the block - based discrete cosine transform （ bdct ） suffers from visible blocking artifacts between adjacent image blocks at low bit rates , which reduces the image visual quality 摘要块离散余弦变换在低比特率时其恢复图像的块边界上会出现明显可见的方块效应，从而降低了图像的视觉质量。
The discrete cosine transform can be implemented in a computationally efficient manner with stage i , the input signal is transformed into a corresponding signal constituted uncorrelated variables 第一级滑动离散馀弦变换能够以高计算效率实现，将输入信号变换为一个由互不相关变量组成的对应信号。
The software realizes the discrete cosine transform , huffman coding , rle coding and so on . in addition , the prediction , motion estimation and motion compensation are adopted 实现了dct ( discretecosinetransform )变换、 huffman编码及rle编码等，另外还运用了预测编码、运动估计及运动补偿等技术。
In this paper , we introduced two watermarking channel models and analyzed discrete cosine transform domain ( dct domain ) watermarking channel model for copyright protection of still digital images 在本文中，我们介绍了两种水印信道模型，同时分析了一种用于静态图象版权保护的oct变换域的数字水印信道模型。
In the decoder , an end - of - block ( eob ) position of an incoming block received by the decoder is determined and a discrete cosine transform ( dct ) block type is determined based on the determined eob position 在该解码器部分，将收到的输入区块中决定一区块终止的位置，并根据此区块终止位置决定一种离散馀弦转换区块形式。
Jpeg2000 is the next generation image compression standard . being different from the jpeg standard , it adopts the two - dimensional discrete wavelet transform ( 2d dwt ) while the jpeg adopts the discrete cosine transform Jpeg2000是新一代图像压缩标准,它放弃了传统的jpeg标准所采用的离散余弦变换,而采用了二维离散小波变换( 2ddwt ) 。
Firstly , the relative basic knowledges of information hiding are presented , and then the techniques of digital images based information hiding in the domain of spatial and dct ( discrete cosine transform ) respectively 首先，介绍了信息隐藏的相关基本知识。然后，分别在空间域和dct域对于以静止图像为载体的信息隐藏技术进行了探讨。
The cosine transform spectrum of sphere are about the same as that of infinite horizontal cylinder , and that of infinite stretched staircase are very sharp , but that of finite stretched staircase presents well - regulated leap 球体与无限长水平圆柱体的余弦变换谱相似，无限延伸垂直台阶的变化很尖锐，有限台阶的表现为上、下有规律的跳跃。
