测试图片:
code:
方案1:
#include "cv.h"
#include "highgui.h"
#define HDIM 256 // bin of HIST, default = 256
int main( int argc, char** argv )
{
IplImage *src = 0, *dst = 0;
CvHistogram *hist = 0;
int n = HDIM;
double nn[HDIM];
uchar T[HDIM];
CvMat *T_mat;
int x;
int sum = 0; // sum of pixels of the source image 图像中象素点的总和
double val = 0;
src=cvLoadImage("1.jpg", 0);
cvNamedWindow( "source", 1 );
cvNamedWindow( "result", 1 );
// calculate histgram 计算直方图
hist = cvCreateHist( 1, &n, CV_HIST_ARRAY, 0, 1 );
cvCalcHist( &src, hist, 0, 0 );
// Create Accumulative Distribute Function of histgram
val = 0;
for ( x = 0; x < n; x++)
{
val = val + cvGetReal1D (hist->bins, x);
nn[x] = val;
}
// Compute intensity transformation 计算变换函数的离散形式
sum = src->height * src->width;
for( x = 0; x < n; x++ )
{
T[x] = (uchar) (255 * nn[x] / sum); // range is [0,255]
}
// Do intensity transform for source image
dst = cvCloneImage( src );
T_mat = cvCreateMatHeader( 1, 256, CV_8UC1 );
cvSetData( T_mat, T, 0 );
// directly use look-up-table function 直接调用内部函数完成 look-up-table 的过程
cvLUT( src, dst, T_mat );
int y;
for(y=0;yheight;y++)
{
for(x=0;xwidth;x++)
{
int dstV,srcV;
dstV = cvGetReal2D(dst,y,x);
srcV = cvGetReal2D(src,y,x);
int newV ;
newV = (srcV*0.7+dstV*0.4);
newV = newV > 255 ? 255 : newV;
cvSetReal2D(dst,y,x,newV);
}
}
cvShowImage( "source", src );
cvShowImage( "result", dst );
cvWaitKey(0);
cvDestroyWindow("source");
cvDestroyWindow("result");
cvReleaseImage( &src );
cvReleaseImage( &dst );
cvReleaseHist ( &hist );
return 0;
}
效果:
方案2:
#include "stdafx.h"
#include "cv.h"
#include "cxcore.h"
#include "highgui.h"
int main(int argc, char* argv[])
{
IplImage* src;
src = cvLoadImage("1.jpg");
IplImage* srcSmooth;
srcSmooth= cvCreateImage(cvGetSize(src),8,3);
cvSmooth(src,srcSmooth,CV_GAUSSIAN,35,35,0,0);
IplImage* srcGray=cvCreateImage(cvGetSize(src),8,1);
cvCvtColor(srcSmooth,srcGray,CV_BGR2GRAY);
CvMat* points = cvCreateMat(srcGray->height*srcGray->width , 1 , CV_32FC1);
CvMat* clusters= cvCreateMat(srcGray->height*srcGray->width , 1 , CV_32SC1);
uchar* image_data = (uchar*)srcGray->imageData;
int width_step = srcGray->widthStep;
int x,y;
for(y=0;yheight;y++)
{
for(x=0;xwidth;x++)
{
points->data.fl[y*srcGray->width+x] = (float)(*(image_data + y*width_step + x));
}
}
cvKMeans2(points,3,clusters ,cvTermCriteria(CV_TERMCRIT_EPS+CV_TERMCRIT_ITER,10,1.0));
float cluster_0_count=0,cluster_1_count=0;
float sum_cluster_0 =0 , sum_cluster_1 = 0;
for(y=0;yheight;y++)
{
for(x=0;xwidth;x++)
{
int cluster_id = clusters->data.i[y*srcGray->width+x];
if(cluster_id == 0 || cluster_id==2)
{
sum_cluster_0 = sum_cluster_0 + (float)(*(image_data + y*width_step + x));
cluster_0_count = cluster_0_count + 1;
*(image_data + y*width_step + x) = 255;
}
else if(cluster_id == 1 )
{
sum_cluster_1 = sum_cluster_1 + (float)(*(image_data + y*width_step + x));
*(image_data + y*width_step + x) = (int)cvGetReal2D(srcGray,y,x);
}
else
{
}
}
}
cvNamedWindow("src");
cvShowImage("src",src);
cvNamedWindow("s");
cvShowImage("s",srcSmooth);
cvNamedWindow("g");
cvShowImage("g",srcGray);
cvWaitKey(0);
return 0;
}
效果: