www.pudn.com > VC_视频捕捉与帧处理.rar > FrameGrabber.cpp

// CFrameGrabber.cpp : implementation file 
// 
// (c) Vadim Gorbatenko, 1999  
// gvv@mail.tomsknet.ru 
// All rights reserved 
// 
// CFrameGrabber window class 
// Release: 1199 
 
#include "stdafx.h" 
#include "FrameGrabber.h" 
 
#define	DEFAULT_CAPTURE_DRIVER	0 //in most cases 
 
#pragma comment(lib, "winmm.lib") 
#pragma comment(lib, "vfw32.lib") 
 
#ifdef _DEBUG 
#define new DEBUG_NEW 
#undef THIS_FILE 
static char THIS_FILE[] = __FILE__; 
#endif 
 
typedef LRESULT (CALLBACK *FRAMECALLBACK)(HWND , LPVIDEOHDR); 
#define	IMAGEWIDTH(lpd) ((LPBITMAPINFOHEADER)lpd)->biWidth 
#define	IMAGEHEIGHT(lpd) ((LPBITMAPINFOHEADER)lpd)->biHeight 
#define	IMAGEBITS(lpd) ((LPBITMAPINFOHEADER)lpd)->biBitCount 
 
LRESULT PASCAL _grabber_CallbackProc(HWND hWnd, LPVIDEOHDR lpVHdr); 
 
CFrameGrabber	*theOnlyOneGrabber = NULL; 
///////////////////////////////////////////////////////////////////////////// 
// CFrameGrabber 
 
CFrameGrabber::CFrameGrabber() 
{ 
	dwLastCallback = NULL; 
	imageData = NULL; 
	vfs = 0;//offset image buffer 
} 
 
CFrameGrabber::~CFrameGrabber() 
{ 
	if(imageData) 
	{	HGLOBAL hg = GlobalHandle(imageData); 
		GlobalUnlock(hg); 
		GlobalFree(hg);} 
} 
 
 
BEGIN_MESSAGE_MAP(CFrameGrabber, CWnd) 
	//{{AFX_MSG_MAP(CFrameGrabber) 
	ON_WM_DESTROY() 
	//}}AFX_MSG_MAP 
END_MESSAGE_MAP() 
 
 
///////////////////////////////////////////////////////////////////////////// 
// CFrameGrabber message handlers 
// create unvisible child window at (x,y) 
BOOL CFrameGrabber::Create(int x, int y, CWnd *pParentWnd) 
{ 
	if(theOnlyOneGrabber) 
		return FALSE; 
 
	ASSERT(!GetSafeHwnd()); 
	 
	if(GetSafeHwnd()) { 
		return FALSE;		//already created 
		} 
	 
	HWND hWnd=capCreateCaptureWindow(_T("AviCap_FrameGrabber_lite"), 
        							WS_CHILD|WS_CLIPSIBLINGS, x, y, 160, 120,  
									pParentWnd?pParentWnd->GetSafeHwnd():NULL, 0xffff); 
	if(!hWnd) 
		return FALSE; 
	 
	//initial setup for capture 
	if( !capDriverConnect(hWnd, DEFAULT_CAPTURE_DRIVER)|| 
		!capSetCallbackOnFrame(hWnd, _grabber_CallbackProc)|| 
		!capPreview(hWnd, FALSE)) 
	 
	{::DestroyWindow(hWnd); 
		return FALSE;} 
	//subclass window 
	SubclassWindow(hWnd); 
	 
	update_buffer_size(); 
	if(!imageData) 
	{::DestroyWindow(hWnd); 
		return FALSE;} 
	theOnlyOneGrabber = this; 
	return TRUE; 
} 
 
void CFrameGrabber::OnDestroy()  
{ 
	//disconnect from capture driver 
	if(theOnlyOneGrabber) { 
	capSetCallbackOnFrame(GetSafeHwnd(), NULL); 
	capDriverDisconnect(GetSafeHwnd()); 
	} 
	CWnd::OnDestroy(); 
	theOnlyOneGrabber = NULL; 
} 
 
BOOL	CFrameGrabber::VideoFormatDialog() 
{ 
	if(!GetSafeHwnd())	return FALSE; 
	BOOL r = (BOOL)capDlgVideoFormat(GetSafeHwnd()); 
	update_buffer_size(); 
	return r; 
} 
 
BOOL	CFrameGrabber::VideoSourceDialog() 
{ 
	if(!GetSafeHwnd())	return FALSE; 
	BOOL r =(BOOL)capDlgVideoSource(GetSafeHwnd()); 
	update_buffer_size(); 
	return r; 
} 
 
LPBITMAPINFO	CFrameGrabber::GetDIB() 
{ 
	if(!imageData)	return NULL; 
	//get the new one of more then 20 ms passed 
	if((timeGetTime()-dwLastCallback)>20) 
		capGrabFrameNoStop(GetSafeHwnd()); 
	return (LPBITMAPINFO)imageData; 
} 
 
LPBYTE			CFrameGrabber::GetImageBitsBuffer() 
{ 
	if(!imageData)	return NULL; 
	//get the new one of more then 20 ms passed 
	if((timeGetTime()-dwLastCallback)>20) 
		capGrabFrameNoStop(GetSafeHwnd()); 
	return ((LPBYTE)imageData)+vfs; 
} 
 
CSize		CFrameGrabber::GetImageSize() 
{ 
	if(!imageData)	return CSize(0,0); 
	else	return CSize(IMAGEWIDTH(imageData), IMAGEHEIGHT(imageData)); 
} 
 
DWORD		CFrameGrabber::GetImageBitsResolution() 
{ 
	if(!imageData)	return 0; 
	else	return IMAGEBITS(imageData); 
} 
 
 
// this is internal use only! 
BOOL	validCallHint=FALSE; 
void	CFrameGrabber::SetImageData(LPVOID data) 
{ 
	ASSERT(validCallHint); 
	// do not call this method indirectly! 
	if(!validCallHint)	return; 
	if(!imageData)		return; 
	CopyMemory(	((LPBYTE)imageData)+vfs, 
				data,  
				IMAGEWIDTH(imageData)*IMAGEHEIGHT(imageData)*IMAGEBITS(imageData)/8); 
	dwLastCallback	=  timeGetTime(); 
	if(IsWindowVisible()) 
		InvalidateRect(NULL); 
 
} 
 
void	CFrameGrabber::update_buffer_size() 
{ 
	vfs=capGetVideoFormatSize(GetSafeHwnd()); 
		if(!vfs) 
		{ 
			if(imageData) 
				{HGLOBAL hg = GlobalHandle(imageData); 
				GlobalUnlock(hg); 
				GlobalFree(hg);} 
				vfs = 0; 
				imageData = NULL; 
			return;		 
		} 
 
	DWORD	lastBufferSize=0; 
	if(imageData) 
		lastBufferSize = vfs + 
		IMAGEWIDTH(imageData)*IMAGEHEIGHT(imageData)*IMAGEBITS(imageData)/8; 
	 
	DWORD newBufferSize; 
	 
 
	BITMAPINFO *lpBmpInfo =(BITMAPINFO	*)( new char[vfs]); 
	 
	((LPBITMAPINFOHEADER)lpBmpInfo)->biSize= sizeof BITMAPINFOHEADER; 
	 
	if(!capGetVideoFormat(GetSafeHwnd(), lpBmpInfo, (WORD)vfs)) 
	{ 
		delete lpBmpInfo; 
		 
		if(imageData) 
			{HGLOBAL hg = GlobalHandle(imageData); 
			GlobalUnlock(hg); 
			GlobalFree(hg);} 
			vfs = 0; 
			imageData = NULL; 
		return;		 
	} 
 
	newBufferSize = vfs + IMAGEWIDTH(lpBmpInfo)*IMAGEHEIGHT(lpBmpInfo)*IMAGEBITS(lpBmpInfo)/8; 
	 
	SetWindowPos(NULL,0,0,IMAGEWIDTH(lpBmpInfo),IMAGEHEIGHT(lpBmpInfo), 
				SWP_NOMOVE|SWP_NOZORDER); 
 
	if(newBufferSize > lastBufferSize) 
	{ 
		if(imageData)//reallocate 
		{	HGLOBAL hg = GlobalHandle(imageData); 
			GlobalUnlock(hg); 
			GlobalFree(hg);} 
 
		imageData = GlobalLock(GlobalAlloc(GMEM_MOVEABLE, newBufferSize+256/*add 256 bytes, just in case...*/)); 
	} 
 
	memcpy(imageData, lpBmpInfo, vfs); 
	 
	delete lpBmpInfo; 
} 
 
////////////////////////////////////////////////////////////////// 
LRESULT PASCAL _grabber_CallbackProc(HWND hWnd, LPVIDEOHDR lpVHdr) 
{ 
	 
	ASSERT_VALID(theOnlyOneGrabber); 
	validCallHint = TRUE; 
	theOnlyOneGrabber ->SetImageData(lpVHdr->lpData); 
	validCallHint = FALSE; 
	return 0; 
}