原文链接 http://blog.csdn.net/yanzi1225627/article/details/8600169
六种方法分别是:基于RGB分割,基于RG同道的分割,ycrcb+otsu(ostu可以参考http://blog.csdn.net/onezeros/article/details/6136770,
http://wenku.baidu.com/view/05c47e03bed5b9f3f90f1ce4.html),YCrCb空间,YUV空间,HSV空间。下一步就是通过JNI将这些检测移植到android上,最终目标是实现Android智能手机利用掌纹开关机。
环境是在qt下,.pro文件里增加如下代码:
- INCLUDEPATH += /usr/include/opencv
- LIBS += /usr/lib/libcv.so \
- /usr/lib/libcvaux.so \
- /usr/lib/libcxcore.so \
- /usr/lib/libhighgui.so \
- /usr/lib/libml.so
请看源码:
- #include <iostream>
- #include "cv.h"
- #include "highgui.h"
- void SkinRGB(IplImage* rgb,IplImage* _dst);
- void cvSkinRG(IplImage* rgb,IplImage* gray);
- void cvThresholdOtsu(IplImage* src, IplImage* dst);
- void cvSkinOtsu(IplImage* src, IplImage* dst);
- void cvSkinYCbCr(IplImage* img, IplImage* mask);
- void cvSkinYUV(IplImage* src,IplImage* dst);
- void cvSkinHSV(IplImage* src,IplImage* dst);
- using namespace std;
- // skin region location using rgb limitation
- int main()
- {
- IplImage *srcImg = cvLoadImage("/home/yan/download/testPalm4.jpg", 1);
- IplImage *dstRGB = cvCreateImage(cvGetSize(srcImg), 8, 3);
- IplImage *dstRG = cvCreateImage(cvGetSize(srcImg), 8, 1);
- IplImage* dst_crotsu=cvCreateImage(cvGetSize(srcImg),8,1);
- IplImage* dst_ycbcr=cvCreateImage(cvGetSize(srcImg),8,1);
- IplImage* dst_yuv=cvCreateImage(cvGetSize(srcImg),8,3);
- IplImage* dst_hsv=cvCreateImage(cvGetSize(srcImg),8,3);
- SkinRGB(srcImg, dstRGB);
- cvSaveImage("/home/yan/download/1_dstRGB.jpg", dstRGB);
- cvSkinRG(srcImg, dstRG);
- cvSaveImage("/home/yan/download/2_dstRG.jpg", dstRG);
- cvSkinOtsu(srcImg, dst_crotsu);
- cvSaveImage("/home/yan/download/3_dst_crotsu.jpg", dst_crotsu);
- cvSkinYCbCr(srcImg, dst_ycbcr);
- cvSaveImage("/home/yan/download/4_dst_ycbcr.jpg", dst_ycbcr);
- cvSkinYUV(srcImg, dst_yuv);
- cvSaveImage("/home/yan/download/5_dst_yuv.jpg", dst_yuv);
- cvSkinHSV(srcImg, dst_hsv);
- cvSaveImage("/home/yan/download/6_dst_hsv.jpg", dst_hsv);
- cvNamedWindow("srcImg", 1);
- cvShowImage("srcImg", srcImg);
- cvNamedWindow("dstRGB", 1);
- cvShowImage("dstRGB", dstRGB);
- cvNamedWindow("dstRG", 1);
- cvShowImage("dstRG", dstRG);
- cvNamedWindow("dstcrotsu", 1);
- cvShowImage("dstcrotsu", dst_crotsu);
- cvNamedWindow("dst_ycbcr", 1);
- cvShowImage("dst_ycbcr", dst_ycbcr);
- cvNamedWindow("dst_yuv", 1);
- cvShowImage("dst_yuv", dst_yuv);
- cvNamedWindow("dst_hsv", 1);
- cvShowImage("dst_hsv", dst_hsv);
- cvWaitKey(0);
- cout << "Hello World!" << endl;
- return 0;
- }
- void SkinRGB(IplImage* rgb,IplImage* _dst)
- {
- cout<<"111"<<endl;
- assert(rgb->nChannels==3&& _dst->nChannels==3);
- static const int R=2;
- static const int G=1;
- static const int B=0;
- IplImage* dst=cvCreateImage(cvGetSize(_dst),8,3);
- cvZero(dst);
- for (int h=0;h<rgb->height;h++) {
- unsigned char* prgb=(unsigned char*)rgb->imageData+h*rgb->widthStep;
- unsigned char* pdst=(unsigned char*)dst->imageData+h*dst->widthStep;
- for (int w=0;w<rgb->width;w++) {
- if ((prgb[R]>95 && prgb[G]>40 && prgb[B]>20 &&
- prgb[R]-prgb[B]>15 && prgb[R]-prgb[G]>15/*&&
- !(prgb[R]>170&&prgb[G]>170&&prgb[B]>170)*/)||//uniform illumination
- (prgb[R]>200 && prgb[G]>210 && prgb[B]>170 &&
- abs(prgb[R]-prgb[B])<=15 && prgb[R]>prgb[B]&& prgb[G]>prgb[B])//lateral illumination
- ) {
- memcpy(pdst,prgb,3);
- }
- prgb+=3;
- pdst+=3;
- }
- }
- cvCopyImage(dst,_dst);
- cvReleaseImage(&dst);
- }
- void cvSkinRG(IplImage* rgb,IplImage* gray)
- {
- assert(rgb->nChannels==3&&gray->nChannels==1);
- const int R=2;
- const int G=1;
- const int B=0;
- double Aup=-1.8423;
- double Bup=1.5294;
- double Cup=0.0422;
- double Adown=-0.7279;
- double Bdown=0.6066;
- double Cdown=0.1766;
- for (int h=0; h<rgb->height; h++)
- {
- unsigned char* pGray=(unsigned char*)gray->imageData+h*gray->widthStep;
- unsigned char* pRGB=(unsigned char* )rgb->imageData+h*rgb->widthStep;
- for (int w=0; w<rgb->width; w++)
- {
- int s=pRGB[R]+pRGB[G]+pRGB[B];
- double r=(double)pRGB[R]/s;
- double g=(double)pRGB[G]/s;
- double Gup=Aup*r*r+Bup*r+Cup;
- double Gdown=Adown*r*r+Bdown*r+Cdown;
- double Wr=(r-0.33)*(r-0.33)+(g-0.33)*(g-0.33);
- if (g<Gup && g>Gdown && Wr>0.004)
- {
- *pGray=255;
- }
- else
- {
- *pGray=0;
- }
- pGray++;
- pRGB+=3;
- }
- }
- }
- void cvThresholdOtsu(IplImage* src, IplImage* dst)
- {
- int height=src->height;
- int width=src->width;
- //histogram
- float histogram[256]= {0};
- for(int i=0; i<height; i++)
- {
- unsigned char* p=(unsigned char*)src->imageData+src->widthStep*i;
- for(int j=0; j<width; j++)
- {
- histogram[*p++]++;
- }
- }
- //normalize histogram
- int size=height*width;
- for(int i=0; i<256; i++)
- {
- histogram[i]=histogram[i]/size;
- }
- //average pixel value
- float avgValue=0;
- for(int i=0; i<256; i++)
- {
- avgValue+=i*histogram[i];
- }
- int threshold;
- float maxVariance=0;
- float w=0,u=0;
- for(int i=0; i<256; i++)
- {
- w+=histogram[i];
- u+=i*histogram[i];
- float t=avgValue*w-u;
- float variance=t*t/(w*(1-w));
- if(variance>maxVariance)
- {
- maxVariance=variance;
- threshold=i;
- }
- }
- cvThreshold(src,dst,threshold,255,CV_THRESH_BINARY);
- }
- void cvSkinOtsu(IplImage* src, IplImage* dst)
- {
- assert(dst->nChannels==1&& src->nChannels==3);
- IplImage* ycrcb=cvCreateImage(cvGetSize(src),8,3);
- IplImage* cr=cvCreateImage(cvGetSize(src),8,1);
- cvCvtColor(src,ycrcb,CV_BGR2YCrCb);
- cvSplit(ycrcb,0,cr,0,0);
- cvThresholdOtsu(cr,cr);
- cvCopyImage(cr,dst);
- cvReleaseImage(&cr);
- cvReleaseImage(&ycrcb);
- }
- void cvSkinYCbCr(IplImage* img, IplImage* mask)
- {
- CvSize imageSize = cvSize(img->width, img->height);
- IplImage *imgY = cvCreateImage(imageSize, IPL_DEPTH_8U, 1);
- IplImage *imgCr = cvCreateImage(imageSize, IPL_DEPTH_8U, 1);
- IplImage *imgCb = cvCreateImage(imageSize, IPL_DEPTH_8U, 1);
- IplImage *imgYCrCb = cvCreateImage(imageSize, img->depth, img->nChannels);
- cvCvtColor(img,imgYCrCb,CV_BGR2YCrCb);
- cvSplit(imgYCrCb, imgY, imgCr, imgCb, 0);
- int y, cr, cb, l, x1, y1, value;
- unsigned char *pY, *pCr, *pCb, *pMask;
- pY = (unsigned char *)imgY->imageData;
- pCr = (unsigned char *)imgCr->imageData;
- pCb = (unsigned char *)imgCb->imageData;
- pMask = (unsigned char *)mask->imageData;
- cvSetZero(mask);
- l = img->height * img->width;
- for (int i = 0; i < l; i++){
- y = *pY;
- cr = *pCr;
- cb = *pCb;
- cb -= 109;
- cr -= 152
- ;
- x1 = (819*cr-614*cb)/32 + 51;
- y1 = (819*cr+614*cb)/32 + 77;
- x1 = x1*41/1024;
- y1 = y1*73/1024;
- value = x1*x1+y1*y1;
- if(y<100) (*pMask)=(value<700) ? 255:0;
- else (*pMask)=(value<850)? 255:0;
- pY++;
- pCr++;
- pCb++;
- pMask++;
- }
- cvReleaseImage(&imgY);
- cvReleaseImage(&imgCr);
- cvReleaseImage(&imgCb);
- cvReleaseImage(&imgYCrCb);
- }
- void cvSkinYUV(IplImage* src,IplImage* dst)
- {
- IplImage* ycrcb=cvCreateImage(cvGetSize(src),8,3);
- //IplImage* cr=cvCreateImage(cvGetSize(src),8,1);
- //IplImage* cb=cvCreateImage(cvGetSize(src),8,1);
- cvCvtColor(src,ycrcb,CV_BGR2YCrCb);
- //cvSplit(ycrcb,0,cr,cb,0);
- static const int Cb=2;
- static const int Cr=1;
- static const int Y=0;
- //IplImage* dst=cvCreateImage(cvGetSize(_dst),8,3);
- cvZero(dst);
- for (int h=0; h<src->height; h++)
- {
- unsigned char* pycrcb=(unsigned char*)ycrcb->imageData+h*ycrcb->widthStep;
- unsigned char* psrc=(unsigned char*)src->imageData+h*src->widthStep;
- unsigned char* pdst=(unsigned char*)dst->imageData+h*dst->widthStep;
- for (int w=0; w<src->width; w++)
- {
- if (pycrcb[Cr]>=133&&pycrcb[Cr]<=173&&pycrcb[Cb]>=77&&pycrcb[Cb]<=127)
- {
- memcpy(pdst,psrc,3);
- }
- pycrcb+=3;
- psrc+=3;
- pdst+=3;
- }
- }
- //cvCopyImage(dst,_dst);
- //cvReleaseImage(&dst);
- }
- void cvSkinHSV(IplImage* src,IplImage* dst)
- {
- IplImage* hsv=cvCreateImage(cvGetSize(src),8,3);
- //IplImage* cr=cvCreateImage(cvGetSize(src),8,1);
- //IplImage* cb=cvCreateImage(cvGetSize(src),8,1);
- cvCvtColor(src,hsv,CV_BGR2HSV);
- //cvSplit(ycrcb,0,cr,cb,0);
- static const int V=2;
- static const int S=1;
- static const int H=0;
- //IplImage* dst=cvCreateImage(cvGetSize(_dst),8,3);
- cvZero(dst);
- for (int h=0; h<src->height; h++)
- {
- unsigned char* phsv=(unsigned char*)hsv->imageData+h*hsv->widthStep;
- unsigned char* psrc=(unsigned char*)src->imageData+h*src->widthStep;
- unsigned char* pdst=(unsigned char*)dst->imageData+h*dst->widthStep;
- for (int w=0; w<src->width; w++)
- {
- if (phsv[H]>=7&&phsv[H]<=29)
- {
- memcpy(pdst,psrc,3);
- }
- phsv+=3;
- psrc+=3;
- pdst+=3;
- }
- }
- //cvCopyImage(dst,_dst);
- //cvReleaseImage(&dst);
- }
下面是效果图:
测试图片:
下图的贴图依次对应上面的六种方法:
从上面的结果对比图中可以清晰看的,ycrcb+ostu的效果无疑是最好的。其次是rgb和yuv方法。这个图片效果之所以这么好是因为测试图片拍摄的时候背景为白色。然后,遗憾的是,当背景色不纯的时候,比如有红也有黑,效果就很不理想了。实验发现,当背景为纯色,且是白色或黑色时,效果最好。
参考:
http://blog.sina.com.cn/s/blog_9ce5a1b501017otq.html
http://blog.csdn.net/scyscyao/article/details/5468577
http://wenku.baidu.com/view/05c47e03bed5b9f3f90f1ce4.html
http://blog.csdn.net/onezeros/article/details/6136770
--------------------------本掌纹是作者自己的,转载请注明作者yanzi1225627