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,2023/8/15,网络多媒体小组,2,内容提要,2023/8/15,2,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,2023/8/15,网络多媒体小组,3,数字图像概念,2023/8/15,3,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。,2023/8/15,网络多媒体小组,4,介绍常见词,像素RGB灰色图像彩色图像,2023/8/15,网络多媒体小组,5,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,2023/8/15,网络多媒体小组,6,RGB,颜色空间之一-RGB,2023/8/15,网络多媒体小组,7,灰度图像（单色图像）,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。,125,153,158,157,127,0,103,120,129,144,144,150,150,147,150,160,165,160,164,16,67,175,175,166,133,133,154,158,100,116,120,97,74,54,4,118,146,148,150,145,157,164,157,158,162,165,171,155,115,88,155,163,95,112,123,101,137,108,81,71,63,137,142,146,152,159,161,159,154,138,81,78,84,114,167,69,85,59,65,43,85,34,69,78,104,101,117,132,134,149,160,165,158,143,114,99,57,45,51,57,54,46,38,44,38,36,44,36,25,48,115,113,114,124,135,152,168,169,156,75,43,39,41,38,42,41,58,30,44,35,28,69,144,147,57,60,93,106,119,124,131,144,175,177,63,30,30,124,139,65,31,39,61,35,75,51,66,58,167,177,153,58,80,95,108,120,133,155,182,137,84,74,54,61,149,96,36,29,115,71,84,105,6,136,172,175,128,126,114,106,109,115,127,169,187,105,102,5,117,120,131,148,144,113,112,109,115,128,162,193,143,132,124,110,131,97,53,66,129,123,128,114,108,115,102,121,129,125,113,112,111,111,127,162,192,150,129,117,112,107,64,67,73,131,125,112,105,95,88,33,139,132,127,128,134,136,144,140,141,113,120,114,115,122,154,188,159,143,6,138,143,145,138,143,143,141,144,129,118,119,115,112,120,152,186,165,150,139,128,117,109,104,93,140,146,147,145,150,154,147,149,143,132,127,124,117,112,117,142,184,171,144,139,129,119,114,112,100135,143,145,151,150,143,146,142,139,131,131,127,119,115,114,140,190,177,141,135,133,121,120,115,102128,137,141,149,150,148,143,141,136,128,120,122,116,109,116,136,182,182,140,135,130,124,116,109,100131,132,141,143,148,147,143,140,134,125,116,117,108,109,120,130,171,185,133,132,127,120,117,110,36,131,139,136,140,141,140,136,132,121,114,117,109,106,112,130,163,192,130,126,131,132,132,136,140,134,135,128,117,110,113,111,110,112,129,151,196,155,130,127,120,115,103,64,127,132,130,128,134,134,140,132,126,110,102,117,118,114,112,121,152,195,165,123,128,117,115,96,36,123,131,127,129,132,133,134,131,127,112,109,117,114,116,107,116,145,172,1,2023/8/15,网络多媒体小组,8,彩色图像,(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,2023/8/15,网络多媒体小组,9,2023/8/15,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,2023/8/15,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,2023/8/15,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,2023/8/15,网络多媒体小组,13,T（阈值）的确定取决于颜色分布直方图,2023/8/15,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。,2023/8/15,网络多媒体小组,15,对象识别方法,模板匹配法神经网络法,2023/8/15,网络多媒体小组,16,模板匹配,2023/8/15,网络多媒体小组,17,输入图像,2023/8/15,网络多媒体小组,18,数字图像分析应用实例,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 CT技术 癌细胞识别 心电图分析航天和航空技术方面 飞机遥感 卫星遥感资源勘察,2023/8/15,18,人脸识别,2023/8/15,网络多媒体小组,19,模板匹配法人脸识别,2023/8/15,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,2023/8/15,网络多媒体小组,21,SAD差图像,2023/8/15,网络多媒体小组,22,Thank you!,2023/8/15,网络多媒体小组,23,RGB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。,2023/8/15,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,