前三种方式转载:http://blog.csdn.net/onezeros/article/details/6342567
第一种:RGB color space
第二种:RG color space
第三种:Ycrcb之cr分量+otsu阈值化
第四种:YCrCb中133<=Cr<=173 77<=Cb<=127
第五种:HSV中 7<H<29
下一步需要滤波操作 因为检测结果中有许多瑕疵
- #include "highgui.h"
- #include "cv.h"
- // skin region location using rgb limitation
- void SkinRGB(IplImage* rgb,IplImage* _dst)
- {
- 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);
- }
- // skin detection in rg space
- 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;
- }
- }
- }
- // implementation of otsu algorithm
- // author: onezeros#yahoo.cn
- // reference: Rafael C. Gonzalez. Digital Image Processing Using MATLAB
- 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 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);
- }
- int main()
- {
- IplImage* img= cvLoadImage("D:/skin.jpg"); //随便放一张jpg图片在D盘或另行设置目录
- IplImage* dstRGB=cvCreateImage(cvGetSize(img),8,3);
- IplImage* dstRG=cvCreateImage(cvGetSize(img),8,1);
- IplImage* dst_crotsu=cvCreateImage(cvGetSize(img),8,1);
- IplImage* dst_YUV=cvCreateImage(cvGetSize(img),8,3);
- IplImage* dst_HSV=cvCreateImage(cvGetSize(img),8,3);
- cvNamedWindow("inputimage", CV_WINDOW_AUTOSIZE);
- cvShowImage("inputimage", img);
- cvWaitKey(0);
- SkinRGB(img,dstRGB);
- cvNamedWindow("outputimage1", CV_WINDOW_AUTOSIZE);
- cvShowImage("outputimage1", dstRGB);
- cvWaitKey(0);
- cvSkinRG(img,dstRG);
- cvNamedWindow("outputimage2", CV_WINDOW_AUTOSIZE);
- cvShowImage("outputimage2", dstRG);
- cvWaitKey(0);
- cvSkinOtsu(img,dst_crotsu);
- cvNamedWindow("outputimage3", CV_WINDOW_AUTOSIZE);
- cvShowImage("outputimage3", dst_crotsu);
- cvWaitKey(0);
- cvSkinYUV(img,dst_YUV);
- cvNamedWindow("outputimage4", CV_WINDOW_AUTOSIZE);
- cvShowImage("outputimage4", dst_YUV);
- cvWaitKey(0);
- cvSkinHSV(img,dst_HSV);
- cvNamedWindow("outputimage5", CV_WINDOW_AUTOSIZE);
- cvShowImage("outputimage5", dst_HSV);
- cvWaitKey(0);
- return 0;
- }