基于信息熵的灰度图像自动分割代码

#include "cv.h" #include "highgui.h" #include "cxcore.h" #pragma comment(lib, "cv.lib") #pragma comment(lib, "highgui.lib") #pragma comment(lib, "cxcore.lib") typedef enum {back,object} entropy_state; void mcvMaxEntropyThreshold(IplImage *rgbIpl, IplImage *grayIpl) { assert(rgbIpl != NULL); assert(rgbIpl->depth == 8 && grayIpl->depth == 8); int HistogramBins = 256; float HistogramRange1[2]={0,255}; float *HistogramRange[1]={&HistogramRange1[0]}; IplImage* pIpl = cvCreateImage(cvGetSize(rgbIpl), 8, 1); CvHistogram * hist = cvCreateHist(1,&HistogramBins,CV_HIST_ARRAY,HistogramRange); if(rgbIpl->nChannels!=1) { cvCvtColor(rgbIpl, pIpl, CV_RGB2GRAY); } else { cvCopy(rgbIpl, pIpl, NULL); } cvCalcHist(&pIpl, hist); double maxentropy = -1.0; int max_index = -1; for(int i=0;i<HistogramBins;i++) { double cur_entropy = caculateCurrentEntropy(hist,i,object)+caculateCurrentEntropy(hist,i,back); if(cur_entropy>maxentropy){ maxentropy = cur_entropy; max_index = i; } } cvThreshold(pIpl, grayIpl, (double)max_index, 255, CV_THRESH_TOZERO); cvReleaseHist(&hist); cvReleaseImage(&pIpl); } double caculateCurrentEntropy(CvHistogram *Histogram1, int cur_threshold, entropy_state state) { int start,end; if(state == back) { start = 0;end = cur_threshold; } else { start = cur_threshold;end = 256; } int total = 0; for(int i=start;i<end;i++) { total += (int)cvQueryHistValue_1D(Histogram1,i); } double cur_entropy = 0.0; for(i=start;i<end;i++){ if((int)cvQueryHistValue_1D(Histogram1,i)==0) continue; double percentage = cvQueryHistValue_1D(Histogram1,i)/total; cur_entropy += -percentage*logf(percentage); } return cur_entropy; }