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。
( 5 ) the performance of the watermark algorithm can be improved by combining the discrete wavelet transform with the discrete cosine and marking full use of the characteristic of the two transforms ( 5 )把离散小波变换和离散余弦变换结合起来，利用小波变换的多分辨率特性及离散余弦变换的解相关能力和聚能作用，可提高水印算法的性能。
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 ) 。
( 3 ) hi the discrete cosine domain , the watermark is embedded by quantifying the coefficient of the dct domain and the quantification procession is given ; the watermark can be extracted without the original audio ( 3 )在离散余弦变换域，通过对变换域系数进行量化来嵌入水印信息，给出了量化方案；在水印的提取过程中不需要原始音频信号的参与。
This dissertation selects two - dimension binary image as watermark information , and selects audio as embedding object , and embed the watermark in the coefficient of the dft domain , the dct domain , the dwt domain 本文以直观的二值图像作为水印信息，以音频数据为嵌入对象，分别在离散傅立叶变换域、离散余弦变换域、离散小波变换域的系数上嵌入水印。
Based on the computational structure of the proposed lapped transform , an efficient multiplierless algorithm for the lapped biorthogonal transform ( lbt ) , called integer lapped biorthogonal transform ( intlbt ) , is proposed 利用提升原理，提出整数离散余弦变换算法，以该算法为基础设计了新双正交叠式变换的整数实现算法，其计算只需要少量的移位和加法运算。
By applying generalized gaussian distribution to statistically model the alternating current coefficient of discrete cosine transform , the technology of the blind image watermark is studied and the performance of the new detector is analyzed 摘要根据数字图像离散余弦变换域交流系数的广义高斯分布模型，对盲图像水印技术进行研究，并给出了水印检测器检测性能的理论分析结果。
In this algorithm , the intuitionistic property is assured by using the binary image as the watermark ; discrete cosine transform and classical edge detection algorithm are adopted to determine the imbedded zones for the watermark 在此算法中，以二值图像作为水印，具有较强的直观性；利用经典的数字图像处理技术中的离散余弦变换和边缘检测算法确定水印嵌入区域并完成水印嵌入。
First of all , the paper discusses the basic theory and means of image and video compression , then attaches more importance to the standards of image and video compression , such as mpeg . as for its realization , there are two ways : soft and hard 更进一步，论文采用veriloghdl语言来描述mpeg的运算核心部分：离散余弦变换( dct )反离散余弦变换( idct ) ，其主要内容是小数的乘加运算在可编程器件中的实现。
