论文标题:基于JPEG2000的数字水印技术的研究
A Contrastive Study on Sino-American Value Orientations--Differences and Similarities
论文作者 樊高峰
论文导师 郭雷,论文学位 硕士,论文专业 模式识别与智能系统
论文单位 西北工业大学,点击次数 183,论文页数 75页File Size7465k
2003-03-01论文网 http://www.lw23.com/lunwen_39499447/ 数字水印;JPEG2000;小波变换;量化;EBCOT;环形自同构
digital watermarking,JPEG2000,wavelet transform,quantize,EBCOT,Toral Autopmorhisms
图像安全随着多媒体技术的蓬勃发展，已经成为一个普遍的而且很重要的问题，数字水印技术是图像安全领域的重要技术的一种，具有优良的发展前途和广阔的市场。JPEG2000是ISO推荐的新一代的静止图像压缩标准，它提供的优越性能决定了未来的图像交换、存储等等格式是JPEG2000。水印算法经过多年的发展也正在走向实用阶段，所以提出了水印算法与JPEG2000压缩算法相结合的必要性，研究基于JPEG2000的嵌入式数字水印技术，实用化的水印应用方案作为研究目的。 论述了压缩算法与水印技术结合必然性，分析了这一论文题目的现实意义和广阔的市场前景。对现行的几种主要算法针对性的作了分析，讨论了JPEG2000的关键技术对嵌入式水印算法的影响，所做的工作具体如下： (1)提出了嵌入式水印算法与压缩算法相结合时，水印算法满足的基本性能，选取了基于量化算法作为水印方案的算法，第二代水印与压缩算法结合的可能性分析。 (2)讨论了压缩技术对水印算法的各种影响，算法相互结合的优缺点，存在的问题，提出了基于JPEG2000的嵌入式水印的基本特征，嵌入式的基本概念就是在压缩编解码器内部嵌入水印嵌入和提取的编解码器，两种算法即充分结合又相互独立的思想。充分结合就是指尽量的减少算法的复杂度，利用压缩算法提供的小波变换、量化等等算法，独立就是水印的算法不影响压缩算法，水印算法作为编解码器的一个模块。设计了在压缩算法中量化之后嵌入水印的方案，对比了两种水印图像的置乱方法混沌序列和环形自同构，详细的讨论了量化大小对水印影响，小波系数对量化步长选取的影响。 (3)实现基于JPEG2000的水印算法的验证平台，对设计的水印方案作了验证，试验表明嵌入式水印算法有自己独特的优点，在压缩比为1：50时仍然可以提取到水印图像。同时也曝露了缺点，对于平滑滤波的抵抗性很差。
The security of image had already been a very normal and very importance question along with the flourish development of multimedia technology. The digital watermarking is the most importance technology in the security of the image, which there is the excellent future and the expansive mark. JPEG 2000 is a new image coding system that uses state-of-the-art compression techniques based on wavelet technology. Its architecture should lend itself to a wide range of uses from portable digital cameras through to advanced pre-press, medical imaging and other key sectors. The technology of digital watermarking is being to the appliance phase passing by the nearly ten years" development, so the ideal that the digital watermarking based on JPEG2000 is put forward which watermarking technology is embed in the JPEGZOOO"s compressing algorithm ,and the research object is applied watermarking scheme.The inevitability of integrating compress algorithm with watermarking algorithm is discuss, and the main work is listed as follows:1. The watermarking must possess several characteristics while the watermarking is embedded in the JPEG2000. The watermarking project adopted the watermarking algorithm based quantize, and some questions must be taken care while the Second Generation Watermarking is applied.2. How the compress algorithm influence on the watermarking algorithm, and pluses and minuses that two algorithm mutually combines was detail analyses. Have put forward the essential features based on embedded watermarking of JPEG2000, The basic conception of embed watermarking in JPEG2000 is that the watermarking algorithm is embed in the compress encoder-decoder. Two kinds of algorithms fully combine and have independency that fully combining reduce algorithm complication referring to utilize the wavelet, quantization and so on and the independence is that the algorithm of the watermarking that which is regarded as a piece of module does not influence the algorithm of compressing. The embedding watermarking scheme that watermarking is embedded after the quantization in compressing algorithms is designed. Compare the confusion based chaos sequence with based toralautopmorhisms, and analyze what the size of quantization of embedded watermarking influences on the robust of watermarking and how to select the size of quantization step according as the magnitude of wavelet transform coefficient. 3. Realize the verification platform watermarking algorithm based on JPEG2000 and test the watermarking scheme that is designed. The testing result indicates that there are one"s own unique advantages in the embedded watermarking algorithm that can still be drawn to the watermarking picture while the compression ratio is 1:50. Expose the shortcoming at the same time that is very poor to the resisting of smooth filtration.
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