数字图像分析及应用.ppt
网络多媒体小组数字图像分析及应用实例2022/11/29网络多媒体小组2内容提要2022/11/292数字图像概念数字图像分析原理步骤数字图像分析应用实例2022/11/29网络多媒体小组3数字图像概念2022/11/293数字图像：将模拟图象通过采样离散化得到数字图像，便于计算机处理。2022/11/29网络多媒体小组4介绍常见词像素RGB灰色图像彩色图像2022/11/29网络多媒体小组5像素像素像素：组成数字图像的元素。每一个像素的坐标对应特定的图像网格位置。像素的数值反映图像中对应位置的亮度。像素2022/11/29网络多媒体小组6RGB颜色空间之一-RGB蓝青品红红黑白绿黄归一化的RGB颜色立方图2022/11/29网络多媒体小组7灰度灰度图像（像（单色色图像）像）每个像素的亮度用一个数值来表示，通常数值范围在0到255之间（一个字节），0表示黑、255表示白，而其它表示灰度。255200100500125,153,158,157,127,0,103,120,129,144,144,150,150,147,150,160,165,160,164,16,67,175,175,166,133,133,154,158,100,116,120,97,74,54,4,118,146,148,150,145,157,164,157,158,162,165,171,155,115,88,155,163,95,112,123,101,137,108,81,71,63,137,142,146,152,159,161,159,154,138,81,78,84,114,167,69,85,59,65,43,85,34,69,78,104,101,117,132,134,149,160,165,158,143,114,99,57,45,51,57,54,46,38,44,38,36,44,36,25,48,115,113,114,124,135,152,168,169,156,75,43,39,41,38,42,41,58,30,44,35,28,69,144,147,57,60,93,106,119,124,131,144,175,177,63,30,30,124,139,65,31,39,61,35,75,51,66,58,167,177,153,58,80,95,108,120,133,155,182,137,84,74,54,61,149,96,36,29,115,71,84,105,6,136,172,175,128,126,114,106,109,115,127,169,187,105,102,5,117,120,131,148,144,113,112,109,115,128,162,193,143,132,124,110,131,97,53,66,129,123,128,114,108,115,102,121,129,125,113,112,111,111,127,162,192,150,129,117,112,107,64,67,73,131,125,112,105,95,88,33,139,132,127,128,134,136,144,140,141,113,120,114,115,122,154,188,159,143,6,138,143,145,138,143,143,141,144,129,118,119,115,112,120,152,186,165,150,139,128,117,109,104,93,140,146,147,145,150,154,147,149,143,132,127,124,117,112,117,142,184,171,144,139,129,119,114,112,100135,143,145,151,150,143,146,142,139,131,131,127,119,115,114,140,190,177,141,135,133,121,120,115,102128,137,141,149,150,148,143,141,136,128,120,122,116,109,116,136,182,182,140,135,130,124,116,109,100131,132,141,143,148,147,143,140,134,125,116,117,108,109,120,130,171,185,133,132,127,120,117,110,36,131,139,136,140,141,140,136,132,121,114,117,109,106,112,130,163,192,130,126,131,132,132,136,140,134,135,128,117,110,113,111,110,112,129,151,196,155,130,127,120,115,103,64,127,132,130,128,134,134,140,132,126,110,102,117,118,114,112,121,152,195,165,123,128,117,115,96,36,123,131,127,129,132,133,134,131,127,112,109,117,114,116,107,116,145,172,12022/11/29网络多媒体小组8彩色图像（255,0,0）（0,255,0）（0,0,255）（123,20,12）（12,135,67）(207,137,130)(220,179,163)(215,169,161)(210,179,172)(210,179,172)(207,154,146)(217,124,121)(226,144,133)(226,144,133)(224,137,124)(227,151,136)(227,151,136)(226,159,142)(227,151,136)(230,170,154)(231,178,163)(231,178,163)(231,178,163)(236,187,171)(236,187,171)(239,195,176)(239,195,176)(240,205,187)(239,195,176)(231,138,123)(217,124,121)(215,169,161)(216,179,170)(216,179,170)(207,137,120)(159,51,71)(189,89,101)(216,111,110)(217,124,121)(227,151,136)(227,151,136)(226,159,142)(226,159,142)(237,159,135)(237,159,135)(231,178,163)(236,187,171)(231,178,163)(236,187,171)(236,187,171)(236,187,171)(239,195,176)(239,195,176)(236,187,171)(227,133,118)(213,142,135)(216,179,170)(221,184,170)(190,89,89)(204,109,113)(204,115,118)(189,85,97)(159,60,78)(136,38,65)(160,56,75)(204,109,113)(227,151,136)(226,159,142)(237,159,135)(227,151,136)(230,170,154)(231,178,163)(230,170,154)(231,178,163)(231,178,163)(236,187,171)(239,195,176)(230,170,154)(204,109,113)(178,73,83)(216,179,170)(220,188,176)(190,77,84)(206,95,97)(217,113,113)(189,85,97)(226,144,133)(207,91,94)(170,56,72)(159,51,71)(150,47,67)(172,63,78)(226,144,133)(226,144,133)(227,151,136)(226,159,142)每个像素的亮度用一个一维向量来表示，各元素分别表示R、G、B通道，数值范围在0到255之间。数字图像分析原理及步骤2022/11/29网络多媒体小组9预处理预处理图像分割图像分割特征提取特征提取对象识别对象识别2022/11/29网络多媒体小组10预处理消除模糊图像去噪图像增强水平矫正图像分割的方法1.基于边缘的分割方法 先提取区域边界，再确定边界限定的区域。2.区域分割 确定每个像素的归属区域，从而形成一个区域图。3.区域生长 将属性接近的连通像素聚集成区域2022/11/29网络多媒体小组11基于边缘的分割方法边缘检测算子（如梯度算子）检测出边缘，再利用光栅跟踪或全向跟踪将边缘像素连成线2022/11/29网络多媒体小组12区域分割利用颜色灰度值判断某一像素点是否属于某特定区域2022/11/29网络多媒体小组13T（阈值）的确定取决于颜色分布直方图2022/11/29网络多媒体小组14区域分割区域生长选定某一像素点，并规定相似性判断标准，如果相邻像素点的相似度达到要求，就将区域有这一点向相邻点生长。直到所有相邻点都不符合相似性要求。2022/11/29网络多媒体小组15对象识别方法模板匹配法神经网络法2022/11/29网络多媒体小组16模板匹配2022/11/29网络多媒体小组17模板输入图像2022/11/29网络多媒体小组18数字图像分析应用实例军事公安方面军事公安方面 指纹识别 人脸鉴别 交通监控生物医学工程方面生物医学工程方面 CT技术 癌细胞识别 心电图分析航天和航空技术方面航天和航空技术方面 飞机遥感 卫星遥感资源勘察2022/11/2918人脸识别2022/11/29网络多媒体小组19模板匹配法人脸识别2022/11/29网络多媒体小组20待识别图像：图像库中图像：相似性度量准则有：归一化互相关(NC)：平方差累加和(SSD)：绝对差累加和(SAD)：识别结果2022/11/29网络多媒体小组21SAD差图像2022/11/29网络多媒体小组22Thank you!2022/11/29网络多媒体小组23RGB颜色分布直方图RGB颜色分布直方图：不同色彩在整幅图像中所占的比例，而并不关心每种色彩所处的空间位置。2022/11/29网络多媒体小组24梯度算子用梯度算子对图像进行处理可以得到图像的边缘
