怎么把bmp图像二值化,变成黑白两色

	CBitmap   m_Bitmap; 

		//m_Bitmap.LoadBitmap()



		m_Bitmap.m_hObject   =   LoadImage(NULL,strFilePath,IMAGE_BITMAP,0,   0,LR_LOADFROMFILE);

		BITMAP btm;

		m_Bitmap.GetBitmap(&btm); 

		if (btm.bmWidth!=104&&btm.bmHeight!=80)

		{

			AfxMessageBox(L"logo像素需符合:104*80!");

			return 0;

		}





#if 1

		CDC dc;

		dc.CreateDC(L"DISPLAY",NULL,NULL,NULL);



	//	BITMAP btm;

		//bm.GetBitmap(&btm);

		DWORD size=btm.bmWidthBytes*btm.bmHeight;

		LPSTR lpData=(LPSTR)GlobalAllocPtr(GPTR,size);

		//BYTE *pBmpBuffer = new BYTE[size];  

		//memset(pBmpBuffer,0,size);

		/////////////////////////////////////////////

		BITMAPINFOHEADER bih;

		bih.biBitCount=btm.bmBitsPixel;

		bih.biClrImportant=0;

		bih.biClrUsed=0;

		bih.biCompression=0;

		bih.biHeight=btm.bmHeight;

		bih.biPlanes=1;

		bih.biSize=sizeof(BITMAPINFOHEADER);

		bih.biSizeImage=size;

		bih.biWidth=btm.bmWidth;

		bih.biXPelsPerMeter=0;

		bih.biYPelsPerMeter=0;

		///////////////////////////////////

		GetDIBits(dc,m_Bitmap,0,bih.biHeight,lpData,(BITMAPINFO*)&bih,DIB_RGB_COLORS);



		//TraceShow(L"logo:",pBmpBuffer,size,0);

	//	TRACE(lpData);



		bih.biBitCount=1;//btm.bmBitsPixel;

		BITMAPFILEHEADER bfh;

		bfh.bfReserved1=bfh.bfReserved2=0;

		bfh.bfType=((WORD)('M'<< 8)|'B');

		bfh.bfSize=54+size;

		bfh.bfOffBits=54;



		CFile bf;

		if(bf.Open(strFilePath+L".bmp",CFile::modeCreate|CFile::modeWrite)){

			bf.Write(&bfh,sizeof(BITMAPFILEHEADER));

			bf.Write(&bih,sizeof(BITMAPINFOHEADER));

			bf.Write(lpData,size);

			bf.Close();

		//	nCount++;

		}

		GlobalFreePtr(lpData);	



		//IFDELS(pBmpBuffer)

		

		m_Bitmap.Detach();

#endif

	Color color,colorTemp;



	Bitmap Bimage(L"C:\\24.bmp");

	int bWidth=Bimage.GetWidth();

	int bHeight=Bimage.GetHeight();

	//graphics.DrawImage(&Bimage,20,bHeight-10,bWidth,bHeight);

	Bitmap* Bimage2=Bimage.Clone(0,0,bWidth,bHeight,PixelFormatDontCare); 

	int i,j,middle;

	for(i=bWidth;i>0;i--)

	{

		for(j=bHeight;j>0;j--)

		{

			Bimage.GetPixel(i,j,&color); 

			middle=(color.GetRed()+color.GetGreen()+color.GetBlue())/3;

			if(middle<128)

				middle=0;

			else

				middle=255;

			Bimage2->SetPixel(i,j,middle); 

		}

	}

	CLSID pngClsid;

	GetEncoderClsid(L"image/bmp", &pngClsid);

BOOL CDib::Load( const TCHAR *pszFilename )

{



	CFile cf;



	// Attempt to open the Dib file for reading.

	if( !cf.Open( pszFilename, CFile::modeRead ) )

		return( FALSE );



	// Get the size of the file and store

	// in a local variable. Subtract the

	// size of the BITMAPFILEHEADER structure

	// since we won't keep that in memory.

	DWORD dwDibSize;

	dwDibSize =cf.GetLength() - sizeof( BITMAPFILEHEADER );



	// Attempt to allocate the Dib memory.

	unsigned char *pDib;

	pDib = new unsigned char [dwDibSize];

	if( pDib == NULL )

		return( FALSE );



	BITMAPFILEHEADER BFH;



	// Read in the Dib header and data.

	try{

		// Did we read in the entire BITMAPFILEHEADER?

		if( cf.Read( &BFH, sizeof( BITMAPFILEHEADER ) )

			!= sizeof( BITMAPFILEHEADER ) ||



			// Is the type 'MB'?

			BFH.bfType != 'MB' ||



			// Did we read in the remaining data?

			cf.Read( pDib, dwDibSize ) != dwDibSize ){



			// Delete the memory if we had any

			// errors and return FALSE.

			delete [] pDib;

			return( FALSE );

			}

		}



	// If we catch an exception, delete the

	// exception, the temporary Dib memory,

	// and return FALSE.

	catch( CFileException *e ){

		e->Delete();

		delete [] pDib;

		return( FALSE );

		}

	

	cf.Close();

	// If we got to this point, the Dib has been

	// loaded. If a Dib was already loaded into

	// this class, we must now delete it.

	if( m_pDib != NULL )

		delete m_pDib;



	// Store the local Dib data pointer and

	// Dib size variables in the class member

	// variables.

	m_pDib = pDib;

	m_dwDibSize = dwDibSize;



	// Pointer our BITMAPINFOHEADER and RGBQUAD

	// variables to the correct place in the Dib data.

	m_pBIH = (BITMAPINFOHEADER *) m_pDib;

	m_pPalette =

		(RGBQUAD *) &m_pDib[sizeof(BITMAPINFOHEADER)];



	// Calculate the number of palette entries.

	m_nPaletteEntries = 1 << m_pBIH->biBitCount;

	if( m_pBIH->biBitCount > 8 )

		m_nPaletteEntries = 0;

	else if( m_pBIH->biClrUsed != 0 )

		m_nPaletteEntries = m_pBIH->biClrUsed;



	// Point m_pDibBits to the actual Dib bits data.

	m_pDibBits =

		&m_pDib[sizeof(BITMAPINFOHEADER)+

			m_nPaletteEntries*sizeof(RGBQUAD)];



	// If we have a valid palette, delete it.

	if( m_Palette.GetSafeHandle() != NULL )

		m_Palette.DeleteObject();



	// If there are palette entries, we'll need

	// to create a LOGPALETTE then create the

	// CPalette palette.

	if( m_nPaletteEntries != 0 ){



		// Allocate the LOGPALETTE structure.

		LOGPALETTE *pLogPal = (LOGPALETTE *) new char

				[sizeof(LOGPALETTE)+

				m_nPaletteEntries*sizeof(PALETTEENTRY)];



		if( pLogPal != NULL ){



			// Set the LOGPALETTE to version 0x300

			// and store the number of palette

			// entries.

			pLogPal->palVersion = 0x300;

			pLogPal->palNumEntries = m_nPaletteEntries;



			// Store the RGB values into each

			// PALETTEENTRY element.

			for( int i=0; i<m_nPaletteEntries; i++ ){

				pLogPal->palPalEntry[i].peRed =

					m_pPalette[i].rgbRed;

				pLogPal->palPalEntry[i].peGreen =

					m_pPalette[i].rgbGreen;

				pLogPal->palPalEntry[i].peBlue =

					m_pPalette[i].rgbBlue;

				}



			// Create the CPalette object and

			// delete the LOGPALETTE memory.

			m_Palette.CreatePalette( pLogPal );

			delete [] pLogPal;

			}

		}



	m_BitCount = 8;

	return( TRUE );



}



BOOL CDib::Save( const TCHAR *pszFilename )

{



	// If we have no data, we can't save.

	if( m_pDib == NULL )

		return( FALSE );



	CFile cf;



	// Attempt to create the file.

	if( !cf.Open( pszFilename,

		CFile::modeCreate | CFile::modeWrite ) )

		return( FALSE );

	

	// Write the data.

	try{



		// First, create a BITMAPFILEHEADER

		// with the correct data.

		BITMAPFILEHEADER BFH;

		memset( &BFH, 0, sizeof( BITMAPFILEHEADER ) );

		BFH.bfType = 'MB';

		BFH.bfSize = sizeof( BITMAPFILEHEADER ) + m_dwDibSize;

		BFH.bfOffBits = sizeof( BITMAPFILEHEADER ) +

			sizeof( BITMAPINFOHEADER ) +

			m_nPaletteEntries * sizeof( RGBQUAD );



		// Write the BITMAPFILEHEADER and the

		// Dib data.

		cf.Write( &BFH, sizeof( BITMAPFILEHEADER ) );

		cf.Write( m_pDib, m_dwDibSize );

		}



	// If we get an exception, delete the exception and

	// return FALSE.

	catch( CFileException *e ){

		e->Delete();

		return( FALSE );

		}



	return( TRUE );



}

bool CDib::ConvertToTwoValue()

{

	DWORD i,size;

	unsigned char *p;

	// 一个特别简单的二值化程序

	// 以128为界划分



	p = m_pDibBits;

	size = m_dwDibSize - (m_pDibBits - m_pDib);

	for (i = 0; i < size;i++)

	{

		if (*p < 128)

		{ 

			*p = 0;

		}

		else

		{

			*p = 255;

		}

		p++;

	}

	return true;



}