VS2015MFC+OpenCV2.4.13（一）：摄像头视频采集和捕获

一、开发平台

Windows 10 X64专业版+VS2015+MFC+OpenCV2.4.13

上述平台配置请见另一篇博文：（待续）

二、开发过程

2.1 新建MFC对话框工程

选择基于对话框，并在下一步中取消掉标题栏之类的东西即可。

2.2 新建一个Dialog

去掉确定按钮，将取消按钮caption改为关闭，并添加两个picture control、三个button，如下图所示。左侧的picture control显示视频，右侧为显示捕获的截图。注意修改ID不要弄混。

2.3 添加Cvvimage头文件

由于自2.X版本后OpenCV取消了对Cvvimage的支持，但是在MFC中使用又需要用到，所以需要手动添加头文件和源文件，代码如下：

（1）Cvvimage.h

#pragma once

#pragma once
#ifndef CVVIMAGE_CLASS_DEF
#define CVVIMAGE_CLASS_DEF
#include "opencv.hpp"
#include 
/* CvvImage class definition */
class  CvvImage
{
public:
	CvvImage();
	virtual ~CvvImage();
	/* Create image (BGR or grayscale) */
	virtual bool  Create(int width, int height, int bits_per_pixel, int image_origin = 0);
	/* Load image from specified file */
	virtual bool  Load(const char* filename, int desired_color = 1);
	/* Load rectangle from the file */
	virtual bool  LoadRect(const char* filename,
		int desired_color, CvRect r);
#if defined WIN32 || defined _WIN32
	virtual bool  LoadRect(const char* filename,
		int desired_color, RECT r)
	{
		return LoadRect(filename, desired_color,
			cvRect(r.left, r.top, r.right - r.left, r.bottom - r.top));
	}
#endif
	/* Save entire image to specified file. */
	virtual bool  Save(const char* filename);
	/* Get copy of input image ROI */
	virtual void  CopyOf(CvvImage& image, int desired_color = -1);
	virtual void  CopyOf(IplImage* img, int desired_color = -1);
	IplImage* GetImage() { return m_img; };
	virtual void  Destroy(void);
	/* width and height of ROI */
	int Width() { return !m_img ? 0 : !m_img->roi ? m_img->width : m_img->roi->width; };
	int Height() { return !m_img ? 0 : !m_img->roi ? m_img->height : m_img->roi->height; };
	int Bpp() { return m_img ? (m_img->depth & 255)*m_img->nChannels : 0; };
	virtual void  Fill(int color);
	/* draw to highgui window */
	virtual void  Show(const char* window);

#if defined WIN32 || defined _WIN32
	/* draw part of image to the specified DC */
	virtual void  Show(HDC dc, int x, int y, int width, int height,
		int from_x = 0, int from_y = 0);
	/* draw the current image ROI to the specified rectangle of the destination DC */
	virtual void  DrawToHDC(HDC hDCDst, RECT* pDstRect);
#endif
protected:
	IplImage*  m_img;
};
typedef CvvImage CImage;
#endif

（2）Cvvimage.cpp

#include "StdAfx.h"
#include "CvvImage.h"
//
// Construction/Destruction
//
CV_INLINE RECT NormalizeRect(RECT r);
CV_INLINE RECT NormalizeRect(RECT r)
{
	int t;
	if (r.left > r.right)
	{
		t = r.left;
		r.left = r.right;
		r.right = t;
	}
	if (r.top > r.bottom)
	{
		t = r.top;
		r.top = r.bottom;
		r.bottom = t;
	}

	return r;
}
CV_INLINE CvRect RectToCvRect(RECT sr);
CV_INLINE CvRect RectToCvRect(RECT sr)
{
	sr = NormalizeRect(sr);
	return cvRect(sr.left, sr.top, sr.right - sr.left, sr.bottom - sr.top);
}
CV_INLINE RECT CvRectToRect(CvRect sr);
CV_INLINE RECT CvRectToRect(CvRect sr)
{
	RECT dr;
	dr.left = sr.x;
	dr.top = sr.y;
	dr.right = sr.x + sr.width;
	dr.bottom = sr.y + sr.height;

	return dr;
}
CV_INLINE IplROI RectToROI(RECT r);
CV_INLINE IplROI RectToROI(RECT r)
{
	IplROI roi;
	r = NormalizeRect(r);
	roi.xOffset = r.left;
	roi.yOffset = r.top;
	roi.width = r.right - r.left;
	roi.height = r.bottom - r.top;
	roi.coi = 0;

	return roi;
}
void  FillBitmapInfo(BITMAPINFO* bmi, int width, int height, int bpp, int origin)
{
	assert(bmi && width >= 0 && height >= 0 && (bpp == 8 || bpp == 24 || bpp == 32));

	BITMAPINFOHEADER* bmih = &(bmi->bmiHeader);

	memset(bmih, 0, sizeof(*bmih));
	bmih->biSize = sizeof(BITMAPINFOHEADER);
	bmih->biWidth = width;
	bmih->biHeight = origin ? abs(height) : -abs(height);
	bmih->biPlanes = 1;
	bmih->biBitCount = (unsigned short)bpp;
	bmih->biCompression = BI_RGB;
	if (bpp == 8)
	{
		RGBQUAD* palette = bmi->bmiColors;
		int i;
		for (i = 0; i < 256; i++)
		{
			palette[i].rgbBlue = palette[i].rgbGreen = palette[i].rgbRed = (BYTE)i;
			palette[i].rgbReserved = 0;
		}
	}
}
CvvImage::CvvImage()
{
	m_img = 0;
}
void CvvImage::Destroy()
{
	cvReleaseImage(&m_img);
}
CvvImage::~CvvImage()
{
	Destroy();
}
bool  CvvImage::Create(int w, int h, int bpp, int origin)
{
	const unsigned max_img_size = 10000;

	if ((bpp != 8 && bpp != 24 && bpp != 32) ||
		(unsigned)w >= max_img_size || (unsigned)h >= max_img_size ||
		(origin != IPL_ORIGIN_TL && origin != IPL_ORIGIN_BL))
	{
		assert(0); // most probably, it is a programming error
		return false;
	}
	if (!m_img || Bpp() != bpp || m_img->width != w || m_img->height != h)
	{
		if (m_img && m_img->nSize == sizeof(IplImage))
			Destroy();
		/* prepare IPL header */
		m_img = cvCreateImage(cvSize(w, h), IPL_DEPTH_8U, bpp / 8);
	}
	if (m_img)
		m_img->origin = origin == 0 ? IPL_ORIGIN_TL : IPL_ORIGIN_BL;
	return m_img != 0;
}
void  CvvImage::CopyOf(CvvImage& image, int desired_color)
{
	IplImage* img = image.GetImage();
	if (img)
	{
		CopyOf(img, desired_color);
	}
}
#define HG_IS_IMAGE(img)                                                  \
   ((img) != 0 && ((const IplImage*)(img))->nSize == sizeof(IplImage) && \
   ((IplImage*)img)->imageData != 0)
void  CvvImage::CopyOf(IplImage* img, int desired_color)
{
	if (HG_IS_IMAGE(img))
	{
		int color = desired_color;
		CvSize size = cvGetSize(img);
		if (color < 0)
			color = img->nChannels > 1;
		if (Create(size.width, size.height,
			(!color ? 1 : img->nChannels > 1 ? img->nChannels : 3) * 8,
			img->origin))
		{
			cvConvertImage(img, m_img, 0);
		}
	}
}
bool  CvvImage::Load(const char* filename, int desired_color)
{
	IplImage* img = cvLoadImage(filename, desired_color);
	if (!img)
		return false;

	CopyOf(img, desired_color);
	cvReleaseImage(&img);

	return true;
}
bool  CvvImage::LoadRect(const char* filename,
	int desired_color, CvRect r)
{
	if (r.width < 0 || r.height < 0) return false;

	IplImage* img = cvLoadImage(filename, desired_color);
	if (!img)
		return false;
	if (r.width == 0 || r.height == 0)
	{
		r.width = img->width;
		r.height = img->height;
		r.x = r.y = 0;
	}
	if (r.x > img->width || r.y > img->height ||
		r.x + r.width < 0 || r.y + r.height < 0)
	{
		cvReleaseImage(&img);
		return false;
	}
	/* truncate r to source image */
	if (r.x < 0)
	{
		r.width += r.x;
		r.x = 0;
	}
	if (r.y < 0)
	{
		r.height += r.y;
		r.y = 0;
	}
	if (r.x + r.width > img->width)
		r.width = img->width - r.x;

	if (r.y + r.height > img->height)
		r.height = img->height - r.y;
	cvSetImageROI(img, r);
	CopyOf(img, desired_color);
	cvReleaseImage(&img);
	return true;
}
bool  CvvImage::Save(const char* filename)
{
	if (!m_img)
		return false;
	cvSaveImage(filename, m_img);
	return true;
}
void  CvvImage::Show(const char* window)
{
	if (m_img)
		cvShowImage(window, m_img);
}
void  CvvImage::Show(HDC dc, int x, int y, int w, int h, int from_x, int from_y)
{
	if (m_img && m_img->depth == IPL_DEPTH_8U)
	{
		uchar buffer[sizeof(BITMAPINFOHEADER) + 1024];
		BITMAPINFO* bmi = (BITMAPINFO*)buffer;
		int bmp_w = m_img->width, bmp_h = m_img->height;
		FillBitmapInfo(bmi, bmp_w, bmp_h, Bpp(), m_img->origin);
		from_x = MIN(MAX(from_x, 0), bmp_w - 1);
		from_y = MIN(MAX(from_y, 0), bmp_h - 1);
		int sw = MAX(MIN(bmp_w - from_x, w), 0);
		int sh = MAX(MIN(bmp_h - from_y, h), 0);
		SetDIBitsToDevice(
			dc, x, y, sw, sh, from_x, from_y, from_y, sh,
			m_img->imageData + from_y*m_img->widthStep,
			bmi, DIB_RGB_COLORS);
	}
}
void  CvvImage::DrawToHDC(HDC hDCDst, RECT* pDstRect)
{
	if (pDstRect && m_img && m_img->depth == IPL_DEPTH_8U && m_img->imageData)
	{
		uchar buffer[sizeof(BITMAPINFOHEADER) + 1024];
		BITMAPINFO* bmi = (BITMAPINFO*)buffer;
		int bmp_w = m_img->width, bmp_h = m_img->height;
		CvRect roi = cvGetImageROI(m_img);
		CvRect dst = RectToCvRect(*pDstRect);
		if (roi.width == dst.width && roi.height == dst.height)
		{
			Show(hDCDst, dst.x, dst.y, dst.width, dst.height, roi.x, roi.y);
			return;
		}
		if (roi.width > dst.width)
		{
			SetStretchBltMode(
				hDCDst,           // handle to device context
				HALFTONE);
		}
		else
		{
			SetStretchBltMode(
				hDCDst,           // handle to device context
				COLORONCOLOR);
		}
		FillBitmapInfo(bmi, bmp_w, bmp_h, Bpp(), m_img->origin);
		::StretchDIBits(
			hDCDst,
			dst.x, dst.y, dst.width, dst.height,
			roi.x, roi.y, roi.width, roi.height,
			m_img->imageData, bmi, DIB_RGB_COLORS, SRCCOPY);
	}
}
void  CvvImage::Fill(int color)
{
	cvSet(m_img, cvScalar(color & 255, (color >> 8) & 255, (color >> 16) & 255, (color >> 24) & 255));
}

2.4 添加消息响应函数

（1）添加“打开摄像头”按钮的消息响应函数

双击“打开摄像头”按钮，进入消息响应函数，修改代码如下：

void CMFCOpenCVTestDlg::OnBnClickedButton1()
{
	// TODO: 在此添加控件通知处理程序代码
	Capture = cvCreateCameraCapture(0); //
	if (Capture == 0)
	{
		MessageBox(_T("无法连接摄像头！！！"));
		return;
	}

	frame = cvQueryFrame(Capture); //从摄像头或者文件中抓取并返回一帧
	pDC = GetDlgItem(IDC_SHOW_VEDIO)->GetDC();//GetDlgItem(IDC_PIC_STATIC)意思为获取显示控件的句柄（句柄就是指针），获取显示控件的DC
	GetDlgItem(IDC_SHOW_VEDIO)->GetClientRect(&rect);
	hDC = pDC->GetSafeHdc();//获取显示控件的句柄

	CvvImage m_CvvImage;
	m_CvvImage.CopyOf(frame, 1); //复制该帧图像   
	m_CvvImage.DrawToHDC(hDC, &rect); //显示到设备的矩形框内
	ReleaseDC(pDC);

	SetTimer(1, 25, NULL); //定时器，定时时间和帧率一致

}

程序中设置了一个定时器，所以需要对对话框类添加一个WM_TIMER的消息，并添加处理函数如下：

void CMFCOpenCVTestDlg::OnTimer(UINT_PTR nIDEvent)
{
	// TODO: 在此添加消息处理程序代码和/或调用默认值
	pDC = GetDlgItem(IDC_SHOW_VEDIO)->GetDC();//GetDlgItem(IDC_PIC_STATIC)意思为获取显示控件的句柄（句柄就是指针），获取显示控件的DC

	GetDlgItem(IDC_SHOW_VEDIO)->GetClientRect(&rect);

	hDC = pDC->GetSafeHdc();//获取显示控件的句柄

	frame = cvQueryFrame(Capture); //从摄像头或者文件中抓取并返回一帧
	CvvImage m_CvvImage;
	m_CvvImage.CopyOf(frame, 1); //复制该帧图像   

	m_CvvImage.DrawToHDC(hDC, &rect); //显示到设备的矩形框内

	CDialogEx::OnTimer(nIDEvent);
}

（2）添加“关闭摄像头”按钮的消息响应函数

双击“关闭摄像头”按钮，进入消息响应函数，修改代码如下：

void CMFCOpenCVTestDlg::OnBnClickedButton2()
{
	// TODO: 在此添加控件通知处理程序代码
	if (!Capture)
	{
		MessageBox(_T("没有打开摄像头！！！"));
		return;
	}

	cvReleaseCapture(&Capture);

	pDC = GetDlgItem(IDC_SHOW_VEDIO)->GetDC();//GetDlgItem(IDC_PIC_STATIC)意思为获取显示控件的句柄（句柄就是指针），获取显示控件的DC

	GetDlgItem(IDC_SHOW_VEDIO)->GetClientRect(&rect);

	hDC = pDC->GetSafeHdc();//获取显示控件的句柄

	frame = cvLoadImage("C:\\Users\\12803\\Documents\\Visual Studio 2015\\Projects\\MFCOpenCVTest\\MFCOpenCVTest\\test.jpg"); //图片读取路径可以自己设定
	CvvImage m_CvvImage;
	m_CvvImage.CopyOf(frame, 1); //复制该帧图像   
	m_CvvImage.DrawToHDC(hDC, &rect); //显示到设备的矩形框内
	ReleaseDC(pDC);
}

（3）添加“截图”按钮的消息响应函数

双击“截图”按钮，进入消息响应函数，修改代码如下：

void CMFCOpenCVTestDlg::OnBnClickedButton3()
{
	// TODO: 在此添加控件通知处理程序代码
	//m_grabframe = cvQueryFrame(Capture);
	m_grabframe = frame;
	if (m_grabframe == 0)
	{
		MessageBox(_T("摄像头已关闭，无法捕捉图像！！！"));
		return;
	}

	CString ImagePath = TEXT("C:\\Users\\12803\\Documents\\Visual Studio 2015\\Projects\\MFCOpenCVTest\\MFCOpenCVTest\\截图");

	//CString ImagePath = _T("D:\\Documents\\Visual Studio 2013\\Projects\\标定图片\\");

	if (!PathIsDirectory(ImagePath))

	{
		CreateDirectory(ImagePath, 0);//不存在则创建
		MessageBox(_T("标定图片文件夹已创建！！！"));
		return;
	}
	char ImagesName[100];

	ImgNum = ImgNum + 1;

	sprintf_s(ImagesName, "%s%.2d%s", "C:\\Users\\12803\\Documents\\Visual Studio 2015\\Projects\\MFCOpenCVTest\\MFCOpenCVTest\\截图", ImgNum, ".jpg");

	IplImage * m_snap = cvCreateImage(cvGetSize(m_grabframe), m_grabframe->depth, m_grabframe->nChannels);
	cvCopy(m_grabframe, m_snap, NULL);
	cvSaveImage(ImagesName, m_snap); //把图像写入指定文件夹的文件中去

									 //以下代码是完成图像的显示过程
	pDC = GetDlgItem(IDC_SHOW_CAPTURE)->GetDC();//GetDlgItem(IDC_PIC_STATIC)意思为获取显示控件的句柄（句柄就是指针），获取显示控件的DC

	GetDlgItem(IDC_SHOW_CAPTURE)->GetClientRect(&rect);

	hDC = pDC->GetSafeHdc();//获取显示控件的句柄

	CvvImage m_CvvImage;
	m_CvvImage.CopyOf(m_snap, 1); //复制该帧图像   
	m_CvvImage.DrawToHDC(hDC, &rect); //显示到设备环境的矩形框内
}

至此代码完成，编译运行结果如图：

 

3. 程序完整代码

完整程序代码已上传，地址：

https://download.csdn.net/download/hankfirst/10885739