例程使用（1-2）共享内存 传递简单结构体

功能：读取USB视频，鼠标点击点（x,y）保存在共享内存

 

发射端

/*  1包含文件  */
//1.1 系统 必选
#include<iostream>
#include<Windows.h>

//1.2 opencv 可选
#include <opencv2/opencv.hpp>  
using namespace cv;
using namespace std;

/*  2自定数据区  */
//2.1 要存储的数据
typedef struct
{
	int x;
	int y;
	/*int zx;
	int zy;*/
	int width;
	int height;
	
	int flag;

}TrackBox; //目标检测的上下顶点；

TrackBox BOX;

/*3 共享内存*/
//3.1内存变量
HANDLE hMapFile;  
LPCTSTR pBuf;
TCHAR szName[] = TEXT("Local\FHY_SYSTEM_0");    //指向同一块共享内存的名字

#define FRAME_SIZE 1920*1080	// 要存的数据大小（图像）
#define BUF_SIZE FRAME_SIZE*10   //分配10倍大
#define BOX_DATA      (char*)pBuf+FRAME_SIZE*0  //数据存储的起始位置

//3.2 初始化
int intShareroom() {

	hMapFile = CreateFileMapping(
		INVALID_HANDLE_VALUE,    // use paging file
		NULL,                    // default security
		PAGE_READWRITE,          // read/write access
		0,                       // maximum object size (high-order DWORD)
		BUF_SIZE,                // maximum object size (low-order DWORD)
		szName);                 // name of mapping object

	if (hMapFile == NULL)
	{
		printf(TEXT("Could not create file mapping object (%d).
"),
			GetLastError());
		return 1;
	}

	pBuf = (LPTSTR)MapViewOfFile(hMapFile,   // handle to map object
		FILE_MAP_ALL_ACCESS, // read/write permission
		0,
		0,
		BUF_SIZE);

	if (pBuf == NULL)
	{
		printf(TEXT("Could not map view of file (%d).
"),
			GetLastError());

		CloseHandle(hMapFile);

		return 1;
	}

}


/* 4 测试 鼠标点击输出 x y 存入共享内存   */
//4.1 鼠标事件
void onMouse(int event, int x, int y, int flags, void* param)
{
	

	//cout << "flag =" << flag << endl;
	Mat *im = reinterpret_cast<Mat*>(param);
	switch (event)
	{
	case CV_EVENT_LBUTTONDOWN:     //鼠标左键按下响应：返回坐标和灰度  
		BOX.x = x;
		BOX.y = y;
		BOX.flag = flags;
		
		cout << "at(" << BOX.x << "," << BOX.y << ")" << "flag =" << BOX.flag << endl;
		//cout << "flag =" << BOX.flag << endl;
		//memcpy(&BOX, BOX_DATA, sizeof(TrackBox));
		
		memcpy(BOX_DATA, &BOX, sizeof(TrackBox));
        //memcpy(&flag, TRANSFER_FLAG, sizeof(int));
		//memcpy(&point, DECTION_BOX_DATA, sizeof(CvPoint));
		break;
	}
}
// 4.2 读取视频 
int imge_test() {

	// 构造一个VideoWriter
	//VideoWriter video("test.avi", CV_FOURCC('M', 'J', 'P', 'G'), 25.0, Size(1920, 1080));
	VideoCapture capture(0);
	if (!capture.isOpened())
	{
		return -1;
	}
	Mat frame;
	capture.set(CV_CAP_PROP_FRAME_WIDTH, 1920);
	capture.set(CV_CAP_PROP_FRAME_HEIGHT, 1080);

	bool stop = false;
	while (1)
	{
		//flag = 0;
		capture >> frame;
		cvNamedWindow("当前视频", 0);

		resize(frame, frame, Size(1920, 1080));
		//Sleep(10);
		cvSetMouseCallback("当前视频", onMouse, &frame);

		imshow("当前视频", frame);
		waitKey(1);

	}

}
	
	
int main()
{   //3 共享内存初始化
	intShareroom();

	//4 图像鼠标点击测试
	imge_test();
	
	//3 共享内存释放
	UnmapViewOfFile(pBuf); //释放；
	CloseHandle(hMapFile);
	return 0;
}

　　接收端

 

#include <windows.h>

#include<iostream>
using namespace std;


// 1.1 定义共享内存
#define FRAME_SIZE 1920*1080                                      // 1单个大小
#define BUF_SIZE FRAME_SIZE*10                                  // 2设置单个成倍数
#define recBOX_DATA      (char*)pBuffer+FRAME_SIZE*0  // 3在共享内存中的存储的开始地址
// 1.2
TCHAR szName[] = TEXT("Local\FHY_SYSTEM_0");     //4指向同一块共享内存的名字
HANDLE hMapFile;   //创建句柄
LPCTSTR pBuffer;


// 2 要发送的数据格式
typedef struct
{
	int x;
	int y;
	int width;
	int height;
	int flag;
}TrackBox; //目标检测的上下顶点；

TrackBox recBOX;

// 3初始化
void  initShareMemory()
{
	hMapFile = CreateFileMapping(
		INVALID_HANDLE_VALUE,    // use paging file
		NULL,                    // default security
		PAGE_READWRITE,          // read/write access
		0,                       // maximum object size (high-order DWORD)
		BUF_SIZE,                // maximum object size (low-order DWORD)
		szName);                 // name of mapping object

	if (hMapFile == NULL)
	{
	
		cout << "Could not create file mapping object" << GetLastError() << endl;
	}
	pBuffer = (LPTSTR)MapViewOfFile(hMapFile,   // handle to map object
		FILE_MAP_ALL_ACCESS, // read/write permission
		0,
		0,
		BUF_SIZE);

	if (pBuffer == NULL)
	{
		printf("Could not map view of file (%d).
",
			GetLastError());
	}
}





void main() {


	initShareMemory();


	while (true)
	{


		// 4 主函数中 使用

		memcpy(&recBOX, recBOX_DATA, sizeof(TrackBox));// 取共享内存值

		int  itarget_x, itarget_y, itarget_h, itarget_w;


		if (recBOX.flag != 0)  // 标志位判断数据是否有效
		{
			itarget_x = recBOX.x;//  中心
			itarget_y = recBOX.y;
			itarget_h = recBOX.height;
			itarget_w = recBOX.width;
			//qDebug("target_x:%d  target_y:%d", recBOX.x, recBOX.y);
		}
		else {

			itarget_x = 1920 / 2;//  中心
			itarget_y = 1080 / 2;
			//qDebug("target_x:%d  target_y:%d", itarget_x, itarget_y);
		}


		cout << "x	" << itarget_x << "	y	" << itarget_y << "	h	" << itarget_h << "	w	" << itarget_w << endl;

	}

}

　　

封装成类

类定义

ShareMemray.h

#pragma once
#ifndef ShareMemray
#define ShareMemray

#include<iostream>
#include<Windows.h>
#include <opencv2/opencv.hpp> 

using namespace cv;
using namespace std;


#define FRAME_SIZE	 1920*1080						// 要存的数据大小（图像）
#define BUF_SIZE	 FRAME_SIZE*10					//分配10倍大
#define BOX_DATA     (char*)pBuf+FRAME_SIZE*0		//数据存储的起始位置 存BOX_DATA  pBuf+FRAME_SIZE*0 -  pBuf+FRAME_SIZE*0+sizeof(TrackBox)  
#define MAT_DATA     (char*)pBuf+FRAME_SIZE*1       //                   存MAT_DATA  pBuf+FRAME_SIZE*1 -  pBuf+FRAME_SIZE*1+sizeof(Mat)

typedef struct
{
	int x;
	int y;

	int width;
	int height;

	int flag;

}TrackBox; //目标检测的上下顶点；




class SHAREDMEMORY {

private:
	TrackBox BOX;
	HANDLE hMapFile;
	LPCTSTR pBuf;
	TCHAR szName[30] = TEXT("Local\FHY_SYSTEM_0");    //指向同一块共享内存的名字


public:

	//1 初始化
	int intShareroom();
	void SendBox(TrackBox BOX);
	void RecBox(TrackBox BOX);
	void stop();	

};






#endif  //SHAREDMEMORY_HPP

　　

　　

文件定义

ShareMemray.cpp

#include "ShareMemray.h"



//3.2 初始化
int SHAREDMEMORY::intShareroom() {

	hMapFile = CreateFileMapping(
		INVALID_HANDLE_VALUE,    // use paging file
		NULL,                    // default security
		PAGE_READWRITE,          // read/write access
		0,                       // maximum object size (high-order DWORD)
		BUF_SIZE,                // maximum object size (low-order DWORD)
		szName);                 // name of mapping object

	if (hMapFile == NULL)
	{
		printf(TEXT("Could not create file mapping object (%d).
"),
			GetLastError());
		return 1;
	}

	pBuf = (LPTSTR)MapViewOfFile(hMapFile,   // handle to map object
		FILE_MAP_ALL_ACCESS, // read/write permission
		0,
		0,
		BUF_SIZE);

	if (pBuf == NULL)
	{
		printf(TEXT("Could not map view of file (%d).
"),
			GetLastError());

		CloseHandle(hMapFile);

		return 1;
	}

}
void SHAREDMEMORY::SendBox(TrackBox BOX) {
	memcpy(BOX_DATA, &BOX, sizeof(TrackBox));
}

void SHAREDMEMORY::RecBox(TrackBox BOX) {
	memcpy(&BOX, BOX_DATA, sizeof(TrackBox));
}


void SHAREDMEMORY::stop() {
	UnmapViewOfFile(pBuf); //释放；
	CloseHandle(hMapFile);
}

　　

发送端

#pragma once
#ifndef MAIN
#define MAIN


/*  1包含文件  */
//1.1 系统 必选
#include<iostream>
#include<Windows.h>
#include "../Include/ShareMemray.h"

//1.2 opencv 可选
#include <opencv2/opencv.hpp> 
using namespace cv;
using namespace std;




TrackBox BOX1;

/* 4 测试 鼠标点击输出 x y 存入共享内存   */
//4.1 鼠标事件
void onMouse(int event, int x, int y, int flags, void* param)
{


	//cout << "flag =" << flag << endl;
	Mat *im = reinterpret_cast<Mat*>(param);
	switch (event)
	{
	case CV_EVENT_LBUTTONDOWN:     //鼠标左键按下响应：返回坐标和灰度 
		BOX1.x = x;
		BOX1.y = y;
		BOX1.flag = flags;

		cout << "at(" << BOX1.x << "," << BOX1.y << ")" << "flag =" << BOX1.flag << endl;
	


		break;
	}
}
// 4.2 读取视频
int imge_test(SHAREDMEMORY sharesend) {

	// 构造一个VideoWriter
	//VideoWriter video("test.avi", CV_FOURCC('M', 'J', 'P', 'G'), 25.0, Size(1920, 1080));
	VideoCapture capture(0);
	if (!capture.isOpened())
	{
		return -1;
	}
	Mat frame;
	capture.set(CV_CAP_PROP_FRAME_WIDTH, 1920);
	capture.set(CV_CAP_PROP_FRAME_HEIGHT, 1080);

	bool stop = false;
	while (1)
	{
		//flag = 0;
		capture >> frame;
		cvNamedWindow("当前视频", 0);

		resize(frame, frame, Size(1920, 1080));
		//Sleep(10);
		cvSetMouseCallback("当前视频", onMouse, &frame);

		imshow("当前视频", frame);
		waitKey(1);

		if (BOX1.flag == 1) {
		
			sharesend.SendBox(BOX1);
			BOX1.flag = 0;
		}

	}

}


int main()
{
	//共享内存初始化
	SHAREDMEMORY sharesend;
	sharesend.intShareroom();
	
	//共享内存发送信息
	imge_test(sharesend);

	//共享内存发送消息
	sharesend.stop();
	
	return 0;
}


#endif

　　

接收端

#include <windows.h>
#include<iostream>
#include "../Include/ShareMemray.h"

using namespace std;


TrackBox recBOX;



void main() {

	SHAREDMEMORY sharerec;
	sharerec.intShareroom();
	


	while (true)
	{


		sharerec.RecBox(recBOX);

		int  itarget_x, itarget_y, itarget_h, itarget_w;


		if (recBOX.flag != 0)  // 标志位判断数据是否有效
		{
			itarget_x = recBOX.x;//  中心
			itarget_y = recBOX.y;
			itarget_h = recBOX.height;
			itarget_w = recBOX.width;
			//qDebug("target_x:%d  target_y:%d", recBOX.x, recBOX.y);
		}
		else {

			itarget_x = 1920 / 2;//  中心
			itarget_y = 1080 / 2;
			//qDebug("target_x:%d  target_y:%d", itarget_x, itarget_y);
		}


		cout << "x	" << itarget_x << "	y	" << itarget_y << "	h	" << itarget_h << "	w	" << itarget_w << endl;

	}
	sharerec.stop();

}

　　

如何发送一个新的自定义结构体

 1在共享内存头文件构造这个结构体

typedef struct
{
	int x;
	int y;

	int width;
	int height;

	int flag;

}TrackBox; //目标检测的上下顶点；

　　

2 在发送类里面加入这个结构体声明

 3 确定在开辟的贡献内存里，分哪一块用来存

 3-1 确认共享内存总的区间，足以存下

总空间名字

总空间大小

3-2 在我我们开辟的共享内存里，分那一块用来存

4 实际存入