介绍用DIB类实现显示BMP图片.doc

1、 ImageProcessingDoc.h文件首先在ImageProcessingDoc.h文件头部添加一下#include语句：#include DibImage.h在ImageProcessingDoc.h文件中添加：public:HDIB GetHDIB() const return m_hDIB; CPalette* GetDocPalette() const return m_palDIB; CSize GetDocSize() const return m_sizeDoc; CDibImage* GetDibImage() const return m_pDibImage; 添加InitDIBData()void InitDIBData();COLORREF m_refColorBKG;添加protected:CDibImage* m_pDibImage;HDIB m_hDIB;CPalette* m_palDIB;CSize m_sizeDoc;void CImageProcessingDoc:InitDIBData()/ 初始化DIB对象if (m_palDIB != NULL)delete m_palDIB;m_palDIB = NULL;if (m_hDIB = NULL)return;LPSTR lpDIB = (LPSTR) :GlobalLock(HGLOBAL) m_hDIB);/ 判断图像是否过大if (m_pDibImage-DIBWidth(lpDIB) INT_MAX |m_pDibImage-DIBHeight(lpDIB) INT_MAX):GlobalUnlock(HGLOBAL) m_hDIB);:GlobalFree(HGLOBAL) m_hDIB);m_hDIB = NULL;CString strMsg;strMsg = BMP图像太大！;MessageBox(NULL, strMsg, 系统提示, MB_ICONINFORMATION | MB_OK);return;m_sizeDoc = CSize(int) m_pDibImage-DIBWidth(lpDIB), (int) m_pDibImage-DIBHeight(lpDIB);:GlobalUnlock(HGLOBAL) m_hDIB);/ 创建新调色板m_palDIB = new CPalette;if (m_palDIB = NULL):GlobalFree(HGLOBAL) m_hDIB);m_hDIB = NULL;return;if (m_pDibImage-CreateDIBPalette(m_hDIB, m_palDIB) = NULL)delete m_palDIB;m_palDIB = NULL;return;BOOL CImageProcessingDoc:OnOpenDocument(LPCTSTR lpszPathName) CFile file;CFileException fe;if (!file.Open(lpszPathName, CFile:modeRead | CFile:shareDenyWrite, &fe)ReportSaveLoadException(lpszPathName, &fe,FALSE, AFX_IDP_FAILED_TO_OPEN_DOC);return FALSE;DeleteContents();BeginWaitCursor();if(m_pDibImage != NULL)delete m_pDibImage;m_pDibImage = NULL;m_pDibImage = new CDibImage;TRYm_hDIB = m_pDibImage-ReadDIBFile(file);CATCH (CFileException, eLoad)file.Abort();EndWaitCursor();ReportSaveLoadException(lpszPathName, eLoad,FALSE, AFX_IDP_FAILED_TO_OPEN_DOC);m_hDIB = NULL;if(m_pDibImage != NULL)delete m_pDibImage;m_pDibImage = NULL;return FALSE;END_CATCHInitDIBData();EndWaitCursor();/ 判断读取文件是否成功if (m_hDIB = NULL)CString strMsg;strMsg = 读取图像时出错！可能是不支持该类型的图像文件！;MessageBox(NULL, strMsg, 系统提示, MB_ICONINFORMATION | MB_OK);if(m_pDibImage != NULL)delete m_pDibImage;m_pDibImage = NULL;return FALSE;SetPathName(lpszPathName);/ 设置文件名称SetModifiedFlag(FALSE);/ 初始化胀标记为FALSEreturn TRUE;2、 最后在CImageProcessingDoc类的构造和析构函数中添加如下代码：CImageProcessingDoc:CImageProcessingDoc()/ TODO: add one-time construction code here/ 默认背景色，灰色m_refColorBKG = 0x00808080;/ 初始化变量m_pDibImage = NULL;m_hDIB = NULL;m_palDIB = NULL;m_sizeDoc = CSize(1,1);CImageProcessingDoc:CImageProcessingDoc()/ 判断DIB对象是否存在if (m_hDIB != NULL)/ 清除DIB对象:GlobalFree(HGLOBAL) m_hDIB);/ 判断调色板是否存在if (m_palDIB != NULL)/ 清除调色板delete m_palDIB;m_palDIB = NULL;/ 判断DibImage对象是否存在if (m_pDibImage != NULL)/ 清除DibImage对象delete m_pDibImage;m_pDibImage = NULL;/3、 /*利用ClassWizard为ImageProcessingView类添加如下代码：CImageProcessingViewWM_ERASEBKGNDOnEraseBkgnd4、 然后在CImageProcessingView.cpp中添加实现上述函数功能的代码：BOOL CImageProcessingView:OnEraseBkgnd(CDC* pDC) / 主要是为了设置子窗体默认的背景色/ 背景色由文档成员变量m_refColorBKG指定CImageProcessingDoc* pDoc = GetDocument();CBrush brush(pDoc-m_refColorBKG); CBrush* pOldBrush = pDC-SelectObject(&brush);CRect rectClip;pDC-GetClipBox(&rectClip);/ 获取重绘区域pDC-PatBlt(rectClip.left, rectClip.top, rectClip.Width(), rectClip.Height(), PATCOPY);pDC-SelectObject(pOldBrush); return TRUE;*/*/*/5、 最后对函数OnDraw和OnPreparePrinting做如下修改：void CImageProcessingView:OnDraw(CDC* pDC)BeginWaitCursor();CImageProcessingDoc* pDoc = GetDocument();ASSERT_VALID(pDoc);HDIB hDIB = pDoc-GetHDIB();if (hDIB != NULL)LPSTR lpDIB = (LPSTR) :GlobalLock(HGLOBAL) hDIB);int cxDIB = (int) pDoc-GetDibImage()-DIBWidth(lpDIB);int cyDIB = (int) pDoc-GetDibImage()-DIBHeight(lpDIB);:GlobalUnlock(HGLOBAL) hDIB);CRect rcDIB;rcDIB.top = rcDIB.left = 0;rcDIB.right = cxDIB;rcDIB.bottom = cyDIB;CRect rcDest;if (pDC-IsPrinting()/ 是打印，计算输出图像的位置和大小，以便符合页面/ 获取打印页面的水平宽度(象素)int cxPage = pDC-GetDeviceCaps(HORZRES);/ 获取打印页面的垂直高度(象素)int cyPage = pDC-GetDeviceCaps(VERTRES);/ 获取打印机每英寸象素数int cxInch = pDC-GetDeviceCaps(LOGPIXELSX);int cyInch = pDC-GetDeviceCaps(LOGPIXELSY);/ 计算打印图像大小（缩放，根据页面宽度调整图像大小）rcDest.top = rcDest.left = 0;rcDest.bottom = (int)(double)cyDIB * cxPage * cyInch)/ (double)cxDIB * cxInch);rcDest.right = cxPage;/ 计算打印图像位置（垂直居中）int temp = c