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MFC 利用opencv实现视频播放

程序员文章站 2024-03-19 23:02:46
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北京时间：2019年5月8日  15时33分

因毕设要求，实现一个视频跟踪算法，算法实现了，现在实现界面化，用opencv2.4.9+MFC实现。

一、创建一个简单的MFC界面

添加控件，一个PICTURE CONTROL 和两个 BUTTON。

MFC 利用opencv实现视频播放

二、添加CvvImage.h和CvvImage.cpp

CvvImage.h和CvvImage.cpp的定义参见附录。

MFC 利用opencv实现视频播放

三、在头文件添加定义

包含头文件：

#include "opencv2/highgui/highgui.hpp"
#include "CvvImage.h"
#include "afxcmn.h"
using namespace cv;

定义变量：

private:       
	CRect rect;
	CStatic* pStc; //标识图像显示的Picture控件
	CDC* pDC; //视频显示控件设备上下文
	HDC hDC; //视频显示控件设备句柄
	CvCapture* capture; //视频获取结构

 如下图。

MFC 利用opencv实现视频播放

四、设置回调函数实现播放

1、什么是回调函数？     通俗理解“回调函数”

2、什么是定时器？怎么通过定时器设置回调函数？ 怎么使用SetTime( )函数

添加定时器

在类向导中添加定时器。

MFC 利用opencv实现视频播放

在OnInitDialog()中添加

pStc=(CStatic *)GetDlgItem(IDC_VIDEO);//IDC_VIDEO为Picture控件ID
pStc->GetClientRect(&rect);//将CWind类客户区的坐标点传给矩形
pDC=pStc->GetDC(); //得到Picture控件设备上下文
hDC=pDC->GetSafeHdc(); //得到控件设备上下文的句柄

onTimer函数如下：

void CplayVideoDlg::OnTimer(UINT_PTR nIDEvent)
{
	// TODO: 在此添加消息处理程序代码和/或调用默认值
	IplImage* m_Frame;  
	m_Frame=cvQueryFrame(capture);  //从视频中取出一幅图像
	CvvImage m_CvvImage;  
	m_CvvImage.CopyOf(m_Frame,1);     
	m_CvvImage.DrawToHDC(hDC, &rect);  //通过句柄hDC，显示

	CDialogEx::OnTimer(nIDEvent);
}

 添加play按钮的函数

void CplayVideoDlg::OnBnClickedButton1()
{
	capture = cvCaptureFromCAM(0);//打开摄像头
	//capture = cvCaptureFromFile("D://1.mp4"); //播放本地文件
	if (!capture)
	{
		MessageBox(L"无法获得摄像头");
		fprintf(stderr, "Can not open camera.\n");
		return;
	}

 
	SetTimer(1,100,NULL);//设置定时器，视频刷新定时器，决定了帧率
}

这样就可以了，也可以把SetTimer(1,100,NULL);改为SetTimer(1,5000,callbackFunction);callbackFunction为自己写的回调函数。

自定义的回调函数如下：

void CALLBACK Func(HDC hDC, CRect rect, CvCapture* capture,bool isplay)
{
	while(isplay)//isplay 在头文件定义
	{
	IplImage* m_Frame;  
	m_Frame=cvQueryFrame(capture);  //从视频中取出一幅图像
	CvvImage m_CvvImage;  
	m_CvvImage.CopyOf(m_Frame,1);     
	m_CvvImage.DrawToHDC(hDC, &rect);  //通过句柄hDC，显示

	}
}


void CplayVideoDlg::OnBnClickedButton1()
{
	capture = cvCaptureFromCAM(0);//打开摄像头
	//capture = cvCaptureFromFile("D://1.mp4"); //播放本地文件
	if (!capture)
	{
		MessageBox(L"无法获得摄像头");
		fprintf(stderr, "Can not open camera.\n");
		return;
	}
	isplay=true;
	Func(hDC,rect,capture,isplay);
	
 
	//SetTimer(1,100,Func);//设置定时器，视频刷新定时器，决定了帧率
}

附录

//CvvImage.h

#pragma once
#ifndef CVVIMAGE_CLASS_DEF
#define CVVIMAGE_CLASS_DEF
#include "opencv.hpp"
/* 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

 //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) );
}

参考博客地址：

https://blog.csdn.net/xiabodan/article/details/41355845

https://blog.csdn.net/angciyu/article/details/80794273

https://www.cnblogs.com/lingc/p/3380919.html

 

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