MFC JPG图片转单色位图代码

以下是使用MFC将JPG图片转换为单色位图的代码：

1. 首先，需要包含以下头文件：

#include <afxwin.h>
#include <afxext.h>
#include <afxcmn.h>
#include <afxdlgs.h>
#include <atlimage.h>

2. 然后，创建一个CImage对象并加载JPG文件：

CImage image;
image.Load(_T("test.jpg"));

3. 接下来，将图像转换为灰度图像：

CImage grayImage;
grayImage.Create(image.GetWidth(), image.GetHeight(), 8);
CDC* pDC = CDC::FromHandle(grayImage.GetDC());
CDC memDC;
memDC.CreateCompatibleDC(pDC);
CBitmap bmp;
bmp.CreateCompatibleBitmap(pDC, image.GetWidth(), image.GetHeight());
CBitmap* pOldBmp = memDC.SelectObject(&bmp);
memDC.BitBlt(0, 0, image.GetWidth(), image.GetHeight(), pDC, 0, 0, SRCCOPY);
memDC.SelectObject(pOldBmp);
grayImage.ReleaseDC();

4. 然后，将灰度图像转换为单色位图：

CImage monoImage;
monoImage.Create(grayImage.GetWidth(), grayImage.GetHeight(), 1);
pDC = CDC::FromHandle(monoImage.GetDC());
pDC->SetStretchBltMode(HALFTONE);
pDC->SetBrushOrg(0, 0);
pDC->BitBlt(0, 0, grayImage.GetWidth(), grayImage.GetHeight(), NULL, 0, 0, WHITENESS);
pDC->SetTextColor(RGB(0, 0, 0));
pDC->SetBkColor(RGB(255, 255, 255));
pDC->BitBlt(0, 0, grayImage.GetWidth(), grayImage.GetHeight(), CDC::FromHandle(grayImage.GetDC()), 0, 0, SRCAND);
monoImage.ReleaseDC();

5. 最后，保存单色位图：

monoImage.Save(_T("test_mono.bmp"), Gdiplus::ImageFormatBMP);

完整代码如下：

#include <afxwin.h>
#include <afxext.h>
#include <afxcmn.h>
#include <afxdlgs.h>
#include <atlimage.h>

void ConvertToMono(LPCTSTR lpszFileName)
{
    CImage image;
    image.Load(lpszFileName);

    CImage grayImage;
    grayImage.Create(image.GetWidth(), image.GetHeight(), 8);
    CDC* pDC = CDC::FromHandle(grayImage.GetDC());
    CDC memDC;
    memDC.CreateCompatibleDC(pDC);
    CBitmap bmp;
    bmp.CreateCompatibleBitmap(pDC, image.GetWidth(), image.GetHeight());
    CBitmap* pOldBmp = memDC.SelectObject(&bmp);
    memDC.BitBlt(0, 0, image.GetWidth(), image.GetHeight(), pDC, 0, 0, SRCCOPY);
    memDC.SelectObject(pOldBmp);
    grayImage.ReleaseDC();

    CImage monoImage;
    monoImage.Create(grayImage.GetWidth(), grayImage.GetHeight(), 1);
    pDC = CDC::FromHandle(monoImage.GetDC());
    pDC->SetStretchBltMode(HALFTONE);
    pDC->SetBrushOrg(0, 0);
    pDC->BitBlt(0, 0, grayImage.GetWidth(), grayImage.GetHeight(), NULL, 0, 0, WHITENESS);
    pDC->SetTextColor(RGB(0, 0, 0));
    pDC->SetBkColor(RGB(255, 255, 255));
    pDC->BitBlt(0, 0, grayImage.GetWidth(), grayImage.GetHeight(), CDC::FromHandle(grayImage.GetDC()), 0, 0, SRCAND);
    monoImage.ReleaseDC();

    monoImage.Save(_T("test_mono.bmp"), Gdiplus::ImageFormatBMP);
}