Its key technology is how to encode image , meanwhile , the technology also is a core problem in multi - media communication , digital broadcast and television 其難點(diǎn)就是數(shù)據(jù)編碼,它也是多媒體通信、多媒體計(jì)算機(jī)和數(shù)字廣播電視的核心技術(shù)。
Compared with the tm5 method , the rate control algorithm can not only increase the encoding images psnr , but also solve the scene change problem 給出的碼率控制算法與傳統(tǒng)的tm5算法相比,不僅使編碼生成的圖像信噪比有所提高,而且解決了場(chǎng)景切換問(wèn)題。
This article which is based on the analysis of field of information security and the research of field of digital image processing , try to develop a system to score encode images ’ robust . with agility method and extreme programming , we successfully develop an experimental system to score encode images 本文基于對(duì)信息安全領(lǐng)域圖片加密現(xiàn)狀的分析以及對(duì)數(shù)字圖像處理的研究,對(duì)圖片加密強(qiáng)壯性的評(píng)估進(jìn)行了嘗試,運(yùn)用敏捷方法的思想和極限編程的手段開(kāi)發(fā)了一個(gè)實(shí)驗(yàn)性的圖片加密強(qiáng)壯性評(píng)估平臺(tái),在軟件工程的指導(dǎo)下保證了整個(gè)平臺(tái)的開(kāi)放性和易于維護(hù)性。
Fractal neighbor distance gives a quantitative measure of the input - output characteristics of the fractal code of an encoded image . the fundamental mechanism behind this recognition scheme lies in the uniqueness of the attractor of a fractal code . the attractor has the invariance to image translation , rotation , scaling and illumination 分形鄰距是針對(duì)進(jìn)行了分形編碼的圖像而定義的一種圖像間相似度的測(cè)距方式,它具有編碼的吸引子唯一不變性的特點(diǎn),因而對(duì)旋轉(zhuǎn)、縮放、平移以及光照都有不變性,這樣可以很好實(shí)現(xiàn)正確識(shí)別。
We used this system to check some representative images on the web , we could got a conclusion that most encode images is easy to decode . without right theory they can ’ t build a robust encoded image . and through thorough experiments by this platform i have concluded such points : single alpha encoded is useless , we must encode all characters as whole ; confusion points are useless , we must use confusion lines which look like stroke ; enlarge base of character such as chinese character , not only digital number and alpha 并且通過(guò)該平臺(tái)的廣泛實(shí)驗(yàn)總結(jié)出增強(qiáng)圖片加密強(qiáng)度的幾個(gè)要點(diǎn):只加強(qiáng)單個(gè)字的加密是不行的,必須把整體作為加密對(duì)象,增強(qiáng)字與字之間的干擾;單純的噪點(diǎn)作用不大,具有筆畫(huà)特征的干擾線作用更大;應(yīng)該引入一些隨機(jī)變量,比如每副圖片的字個(gè)數(shù)隨機(jī),加密方法隨機(jī)選擇;增大可選詞匯的基數(shù),可以考慮使用漢字,而不單純是數(shù)字和英文。