基于opencv的利用cvSetImageROI,WidthStep修改图像区域，以及在区域添加字体

本文介绍了一个使用OpenCV 3.4.2进行图像处理的示例程序，演示了如何增强图像亮度、设置图像区域（ROI）、修改图像的WidthStep属性及在图像上添加文字。该程序基于Visual Studio 2017开发。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

platform:opencv 3.4.2&vs2017

主函数：

#include <iostream>

using namespace std;
#include<opencv2/core/core.hpp>
#include<opencv2/imgproc/imgproc.hpp>
#include<opencv2/highgui/highgui.hpp>
using namespace cv;
#include "area_deal.h"
int main() {
	cvNamedWindow("dog", CV_WINDOW_AUTOSIZE);
	IplImage* dog = cvLoadImage("..//..//dog.bmp");
	area_deal GB_max;
	GB_max.GB_max(dog);
	cvShowImage("dog", dog);
    cvWaitKey(0);
	/*区域ROI*/
	GB_max.Roi(*dog);
	/*区域WidthStep*/
	GB_max.WidthStep(*dog);
	/*添加字*/
	GB_max.font_plus(*dog);
	return 0;
}

增加类：

#pragma once
#include <iostream>

using namespace std;
#include<opencv2/core/core.hpp>
#include<opencv2/imgproc/imgproc.hpp>
#include<opencv2/highgui/highgui.hpp>
#include <cv.h>
#include<highgui.h>
using namespace cv;
class area_deal
{
public:
	area_deal();
	~area_deal();
	void GB_max(IplImage * in);
	void Roi(IplImage in);
	void WidthStep(IplImage in);
	void font_plus(IplImage in);
	
};

#include "area_deal.h"



area_deal::area_deal()
{
}


area_deal::~area_deal()
{
}

void area_deal::GB_max(IplImage * in) {
	for (int row = 0; row < in->height; row++) {
		uchar * ptr = (uchar *)(in->imageData + row * in->widthStep);
		for (int col = 0; col < in->width; col++) {
			if(ptr[3*col+1]<235) ptr[3 * col + 1] += 20;
			if(ptr[3*col+2]<235) ptr[3 * col + 2] += 20;
		}
	}
}

void area_deal::Roi(IplImage in) {
	cvNamedWindow("area_deal_ROI", CV_WINDOW_AUTOSIZE);

	cvSetImageROI(&in, CvRect(100, 100, 50, 50));
	//CvScalar通道顺序是B G R+透明度 
	cvAddS(&in, CvScalar(50), &in);
	cvResetImageROI(&in);

    cvShowImage("area_deal_ROI", &in);
	cvWaitKey(0);
	cvDestroyWindow("area_deal_ROI");
}

void area_deal::WidthStep(IplImage in) {
	cvNamedWindow("area_deal_WidthStep", CV_WINDOW_AUTOSIZE);
	CvRect in_img = CvRect(200, 200, 100, 100);
	IplImage * sub_img = cvCreateImageHeader(CvSize(
	     in_img.width,
		 in_img.height), 
		in.depth, in.nChannels);
	/*origin有两种取值 IPL_ORIGIN_TL与IPL_ORIGIN_BL分别表示坐标原点位于图像的左上角
	或则左下角*/
	sub_img->origin = in.origin;
	sub_img->widthStep = in.widthStep;
	/*sub_img的数据指针指向in图像的（200，200）位置*/
	sub_img->imageData = in.imageData + in_img.width*in.widthStep + in_img.height*in.nChannels;
	cvAddS(sub_img, cvScalar(100), sub_img);
    
	cvReleaseImageHeader(&sub_img);
	cvShowImage("area_deal_WidthStep", &in);
	cvWaitKey(0);
	cvDestroyWindow("area_deal_WidthStep");
}
void area_deal::font_plus(IplImage  in) {
	cvNamedWindow("font_plus", CV_WINDOW_AUTOSIZE);
	CvFont word;
	cvInitFont(&word, CV_FONT_HERSHEY_COMPLEX_SMALL,
		1, 1, 1.0, 1, 8);
	cvPutText(&in, "kris'dog", CvPoint(in.width*0.8,380), &word, CvScalar(0, 100));
	Mat ad = cvarrToMat(&in);
	cvShowImage("font_plus", &in);
	cvWaitKey(0);
    cvDestroyWindow("font_plus");
	imwrite("..//..//area_deal.bmp", ad);
}