//opencv

#include "opencv2/opencv.hpp"

#include "opencv2/highgui/highgui.hpp"

#include "opencv2/imgproc/imgproc.hpp"

/******************************************************************************************

Function:      Screenshot

Description:    矩形截图

Input:          src:原图片  rect:截图范围

Output:        dst:截图后的图片

Return:        截图成功返回true,失败返回false

*******************************************************************************************/

bool Screenshot(IplImage* src, IplImage* dst, CvRect rect)

{

try {

cvSetImageROI(src, rect);

cvCopy(src, dst, 0);

cvResetImageROI(src);

return true;

}

catch (cv::Exception e)

{

}

}

/******************************************************************************************

Function:      SafeResetSizeOfRect

Description:    安全重置矩形大小

Input:          src:原图片 rect:截图范围

Return:        无

*******************************************************************************************/

void SafeResetSizeOfRect(IplImage* src, CvRect& rect)

{

try

{

rect.x = rect.x < 0 ? 0 : rect.x;

rect.y = rect.y < 0 ? 0 : rect.y;

rect.width = rect.width < 0 ? 0 : rect.width;

rect.height = rect.height < 0 ? 0 : rect.height;

if (rect.x > src->width || rect.y > src->height)

{

rect = cvRect(0, 0, src->width, src->height);

}

rect.width = std::min(rect.width, src->width - rect.x);

rect.height = std::min(rect.height, src->height - rect.y);

}

catch (cv::Exception e)

{

}

}

//调用举例

IplImage *src = 0;

IplImage *dst = 0;

src = cvLoadImage("D:\\1.jpg", CV_LOAD_IMAGE_COLOR);

//定义截图范围

CvRect rect = cvRect(720, 610, 300, 320);

//截图

SafeResetSizeOfRect(src, rect);

dst = cvCreateImage(cvSize(rect.width, rect.height), src->depth, src->nChannels);

Screenshot(src, dst, rect);

//保存图片

cvSaveImage("D:\\rect.jpg", dst);

//释放内存

cvReleaseImage(&src);

cvReleaseImage(&dst);