《学习OpenCV》练习题第四章第三题b

 #include <highgui.h>

 #include <cv.h>

 #include "opencv_libs.h"

 /*

  *《学习OpenCV》第四章第三题b

  * 完成时间：1:36 3/31 星期日 2013

  */

 /* 矩形框 */

 CvRect rect;

 bool draw = false;   // 标记是否在画

 IplImage* img;

 IplImage * temp;

 IplImage * original;

 bool draw_hist = false;

 IplImage* getHistImage(IplImage* image, CvHistogram* image_hist,

                        CvSize image_size, CvScalar value)

 {

     // 计算直方图

     cvCalcHist( &image, image_hist, , NULL );

     // 新建一幅3通道的图像

     IplImage* dst = cvCreateImage(image_size, IPL_DEPTH_8U,  );

     cvSet( dst, cvScalarAll() );

     float max_value = ;

     cvGetMinMaxHistValue( image_hist, NULL, &max_value, NULL, NULL );

     double bin_width = (double)dst->width/;

     double bin_unith = (double)dst->height/max_value;   // 高度比例

     for(int i = ; i < ; i++)

     {

         // 获得矩形左上角和右下角坐标

         CvPoint p0 = cvPoint( i + bin_width, dst->height );

         CvPoint p1 = cvPoint( (i+) * bin_width,

             dst->height - cvGetReal1D(image_hist->bins, i) *  bin_unith );

         // 画实心矩形

         cvRectangle( dst, p0, p1, value, -, ,  );

     }

     return dst;

 }

 void draw_rect(IplImage* img, CvRect rect)

 {

     cvRectangle( img,

         cvPoint( rect.x, rect.y ),

         cvPoint( rect.x + rect.width, rect.y + rect.height),

         cvScalar( 0x00, 0x00, 0xff) );

     printf("draw\n");

     // 在这里处理直方图

     // 设置感兴趣区域

     cvSetImageROI( img, rect);

     IplImage* src_rect = cvCreateImage (

         cvSize( rect.width, rect.height ),

         img->depth, img->nChannels );

     cvCopy(img, src_rect );

     cvResetImageROI( img );

     IplImage* r_img = cvCreateImage( cvGetSize( src_rect),

         src_rect->depth,  );

     IplImage* g_img = cvCreateImage( cvGetSize( src_rect),

         src_rect->depth,  );

     IplImage* b_img = cvCreateImage( cvGetSize( src_rect),

         src_rect->depth,  );

     IplImage* gray_img = cvCreateImage( cvGetSize( src_rect),

         src_rect->depth,  );

     // 分离RGB分量

     cvSplit( src_rect, r_img, g_img, b_img, NULL);

     cvShowImage( "red", r_img);

     cvShowImage( "green", g_img);

     cvShowImage( "blue", b_img);

     // 灰度转换

     cvCvtColor( src_rect, gray_img, CV_BGR2GRAY);

     int size = ;

     float range[] = {, };

     float* ranges[] = {range};

     // 创建直方图

     CvHistogram * r_hist = cvCreateHist( , &size, CV_HIST_ARRAY, ranges, );

     CvHistogram * g_hist = cvCreateHist( , &size, CV_HIST_ARRAY, ranges, );

     CvHistogram * b_hist = cvCreateHist( , &size, CV_HIST_ARRAY, ranges, );

     CvHistogram * gray_hist = cvCreateHist( , &size, CV_HIST_ARRAY, ranges, );

     // 直方图尺寸

     CvSize image_size = cvSize( , );

     IplImage* r_dst = getHistImage(r_img, r_hist, image_size, cvScalar(0x00, 0x00, 0xff));

     IplImage* g_dst = getHistImage(g_img, g_hist, image_size, cvScalar(0x00, 0xff, 0x00));

     IplImage* b_dst = getHistImage(b_img, b_hist, image_size, cvScalar(0xff, 0x00, 0x00));

     IplImage* gray_dst = getHistImage( gray_img, gray_hist, image_size, cvScalar() );

     // 把四个直方图在一幅图片上显示出来

     IplImage* dst = cvCreateImage( cvSize( image_size.width * , image_size.height * ), ,  );

     cvSetZero( dst );

     // 拷贝红色分量直方图

     CvRect r_rect = cvRect( , , image_size.width, image_size.height);

     cvSetImageROI(dst, r_rect);

     cvCopy( r_dst, dst);

     // 拷贝绿色分量直方图

     CvRect g_rect = cvRect(image_size.width, , image_size.width, image_size.height );

     cvSetImageROI( dst, g_rect);

     cvCopy( g_dst, dst);

     // 蓝色分量

     CvRect b_rect = cvRect(, image_size.height, image_size.width, image_size.height );

     cvSetImageROI(dst, b_rect);

     cvCopy( b_dst, dst );

     // 灰度分量

     CvRect gray_rect = cvRect( image_size.width, image_size.height,

         image_size.width, image_size.height );

     cvSetImageROI( dst, gray_rect);

     cvCopy( gray_dst, dst);

     cvResetImageROI( dst );

     cvShowImage( "src", src_rect);

     cvShowImage( "dst", dst );

     cvWaitKey();

     cvDestroyAllWindows();

     cvReleaseImage( &r_img );

     cvReleaseImage(&g_img);

     cvReleaseImage(&b_img);

     cvReleaseImage(&gray_img);

     cvReleaseImage(&r_dst);

     cvReleaseImage(&g_dst);

     cvReleaseImage(&b_dst);

     cvReleaseImage(&gray_dst);

     cvReleaseImage(&src_rect);

     cvReleaseImage(&dst);

 }

 // 鼠标回调函数

 void my_mouse_callback( int event, int x, int y, int flags, void* param)

 {

     IplImage* image = (IplImage*) param;

     switch( event )

     {

     case CV_EVENT_MOUSEMOVE:

         {

             if(draw)

             {

                 rect.width = x - rect.x;

                 rect.height = y - rect.y;

             }

             draw_hist = false;

         }

         break;

     case CV_EVENT_LBUTTONDOWN:

         {

             draw = true;

             rect = cvRect( x, y, ,  );

             draw_hist = false;

         }

         break;

     case CV_EVENT_LBUTTONUP:

         {

             draw = false;

             draw_hist = true;

             if(rect.width < )

             {

                 rect.x += rect.width;

                 rect.width *= -;

             }

             if(rect.height < )

             {

                 rect.y += rect.height;

                 rect.height *= -;

             }

             // draw

             draw_rect(image, rect);

         }

         break;

         // 在右键按下时清除

     case CV_EVENT_RBUTTONDOWN:

         cvCopyImage(original, img);

         printf("clear.\n");

         break;

     }

 }

 int main()

 {

     img = cvLoadImage( "lena.bmp",  );

     rect = cvRect( -, -, , );

     // 副本

     temp = cvCloneImage( img );

     original = cvCloneImage(img);

     cvNamedWindow("draw rect");

     cvSetMouseCallback("draw rect", my_mouse_callback, (void*)img);

     while()

     {

         cvCopyImage(img, temp);

         if(draw_hist)

         {

             draw_rect( temp , rect );

         }

         cvShowImage( "draw rect", temp);

         if(cvWaitKey() == )

             break;

     }

     cvReleaseImage(&img);

     cvReleaseImage(&temp);

     cvDestroyAllWindows();

     return ;

 }

运行结果：

不足：在源图像上用鼠标选择矩形区域的时候，无法实时地在图像上反映出来。