In the third part , the essences of steganography and disadvanges of common visual perception evaluation , such as psnr and wpsnr are studied . based on analysis local error that is introduced by embedding information , combining hvs , three objective perception evaluation method for steganography performance are proposed , which are based on human visual systems and local statistic error distribution respectively . in the steganalysis part , a steganography security statistic attack model and methods for some steganography methods are presented 在信息隐藏的性能评价方面，研究了常用的峰值信噪比，加权峰值信噪比等前人提出的感知性能评价准则，指出针对信息隐藏的性能评价不能单纯从视觉特性出发，提出从信息隐藏的数据特性和感知特性出发，结合局部特性来考察失真误差的变化的思想，并据此提出基于局部区域误差统计分布和视觉掩模方法评价信息隐藏性能的方法。
Moreover , experimental results have proved that the method is robust enough to some image degradation process such as cropping , jpeg compression and sharpening etc . embedded zerotree wavelet coding ( ezw ) algorithm , it is found that this algorithm does not make full use of the properties of human visual system ( hvs ) to eliminate visual redundancy 实验证明，该方法对剪裁、 jpeg压缩和锐化等图象退化处理均具有一定的抵抗力，是一种行之有效的水印嵌入方法。本文在对零树编码方法研究的基础上，针对零树编码方法没有充分利用hvs特性来有效消除视觉冗余的缺点，提出了一种基于小波系数的零树编码方案。
Automatic threshold choice is difficult and important to color images edge detection , first of all , on the base of human visual properties , threshold versus intensity function of human visual system are researched and analyzed , by using method of mathematic modeling and the result of saturation research , function of least color difference that can be perceptible by visual systems in detecting edge is given 摘要自动阀值选取是彩色图像边缘检测的难点和关键问题，首先从人类的视觉特性出发，分析了人类视觉系统的亮度感知门限函数，利用数学建模方法和色度学方面的研究成果，给出人类视觉系统对彩色图像边缘所能识别的最小彩色差函数。
In order to improve coding efficiency at low bit - rates , this thesis adopted wavelet and nonlinear matching pursuit techniques , combined with some characteristics of human visual system , aimed at improve the performance of video coding at low bit - rates . the major contributions of this thesis are included in the following : 1 为了提高低速率编码效率，本文综合小波变换以及匹配跟踪非线性信号分解技术，并结合人类视觉系统hvs的各种特性，致力于提高视频编码算法在低速率条件下的编码性能，并对所涉及到的若干问题进行了探索和解决，并取得如下创新性研究成果： 1
High bitrate to the region to which the human visual system is sensitive while low bitrate to the other regions . the reconstructed image with a high compressive rate can still hold fairly good subject quality . 2 . produce embedded bitstreamthe length of each of the three parts stored in the barcode is not fixed , embedded bitstream can make full use of the limited space of the storage media 二维条码中存储的各类信息(比如：指纹、照片和个人信息等)一般都是不定长的，嵌入式码流使得不必采用预留空间的方式，能充分利用存储空间，获得尽可能好的恢复图像。
Makes general analysis and research on human visual system the characteristicness of human visual system is the process being considered firstly for every image process technology , include watermark technology , in order to join the characteristicness of hvs and the watermark technology together , this paper analyses and researches the hvs theoretics particularly firstly . it build the aesthesia models and the jnd models after discussing eyes " biology configuration particularly and expatiating eyes " aesthesia process . these works provide the foundation for the later research of watermark channel capacity and the watetmark embedding intensity . 2 对人类视觉系统的特性进行了全面的分析和研究人类视觉系统的特性是任何图像处理技术必须优先考虑的环节，数字水印技术也不例外，为了使人类视觉系统的特性和数字水印技术很好地结合，本文首先对人类视觉系统理论进行了全面细致的分析和研究，在详细阐述了人眼的生理结构及人眼对颜色的感知过程的基础上，建立了人眼的感知模型和人类视觉系统的jnd模型，这些工作为后来水印信道容量的研究、水印嵌入强度的确定等工作奠定了基础。
This paper also introduces the following contents according to principle of field emission and human visual system ( hvs ) : the display principle of fed panel and pulse width modulation ( pwm ) , the reason why pwm was used in fed system , driving method of pwm and two pwm methods used in present fed sample 此外,论文从场致发射原理和人眼视觉特性出发,介绍了fed显示屏的显示原理和脉冲宽度调制原理( pwm ) ,分析了fed采用pwm工作方式的原因, pwm工作方式实现彩色fed显示的驱动原理,还有目前本实验室fed样机所采用的两种pwm方案。
At last a new image - adaptive waermarking scheme is brought forward , which takes full advatage of the good characters of wavelet bof orm and human visual system based on spread spectri theory and the algorithrn has good robusiness and capacity both the gray - l ev e l - im ag e - adapti ve watermarking system and c o lor - image watermarking system based on the image - adaptive watermarking scheme in the yuv color - mode space are implemented 在保证水印不可见和鲁棒性的前提下，论文基于小波变换提出一种图像自适应的数字水印方案。这种方案以图像为水印，基于扩频原理，充分利用小波变换的优良特点和人眼视觉特性，结合图像自身特性，使嵌入的水印既有良好的鲁棒性又有良好的容量。
It takes full advantage of masking sensitivities of the human visual system ( hvs ) and uses watermark break technique to improve the robustness of the embedded watermarks . experiment results are reported proving the robustness of the proposed algorithm against some of the most common video processing techniques 该算法是在视频压缩域中嵌入水印，它充分利用了hvs模型的各种掩蔽特性来增强水印的稳健性，并通过水印跳变技术增强了水印对统计分析攻击的抵抗能力。
As the multi - resolution property of dwt enable dwt - based watermark system combine the statistic characteristic of image with human visual system , make it possible to find an optimal system . besides , using proposed system test the parameters which work on the system performance , such as embed position , embed strength , watermark structure , image capacity and hvs etc 此外，利用建立的水印模型对影响水印系统的各种因素，包括水印嵌入的位置、嵌入的强度，水印的结构、水印的容量、人类视觉系统对系统性能的影响进行全面的综合分析，为优化系统性能提出一定的可参考的建议。
