我使用的是CxImage http://www.codeproject.com/bitmap/cximage.asp 非常方便的举例: ... convert from a format to another CxImage image; // bmp -> jpg image.Load("image.bmp", CXIMAGE_FORMAT_BMP); if (image.IsValid()){ if(!image.IsGrayScale()) image.IncreaseBpp(24); image.SetJpegQuality(99); image.Save("image.jpg",CXIMAGE_FORMAT_JPG); } // png -> tif image.Load("image.png", CXIMAGE_FORMAT_PNG); if (image.IsValid()){ image.Save("image.tif",CXIMAGE_FORMAT_TIF); }
... convert from a format to another CxImage image; // bmp -> jpg image.Load("image.bmp", CXIMAGE_FORMAT_BMP); if (image.IsValid()){ if(!image.IsGrayScale()) image.IncreaseBpp(24); image.SetJpegQuality(99); image.Save("image.jpg",CXIMAGE_FORMAT_JPG); } // png -> tif image.Load("image.png", CXIMAGE_FORMAT_PNG); if (image.IsValid()){ image.Save("image.tif",CXIMAGE_FORMAT_TIF); }
2.显示(如用OleLoadPicture)后提取dib
http://www.codeproject.com/bitmap/cximage.asp
{
if(filename == "")
{
AfxMessageBox("请先输入文件路径");
return false;
}
HANDLE hFile = CreateFile(filename, GENERIC_READ, 0, NULL, OPEN_EXISTING, 0, NULL);
_ASSERTE(INVALID_HANDLE_VALUE != hFile); // 取得文件大小
DWORD dwFileSize = GetFileSize(hFile, NULL);
_ASSERTE(-1 != dwFileSize);
LPVOID pvData = NULL;
//根据文件大小分配内存
HGLOBAL hGlobal = GlobalAlloc(GMEM_MOVEABLE, dwFileSize);
_ASSERTE(NULL != hGlobal);
pvData = GlobalLock(hGlobal);
_ASSERTE(NULL != pvData);
DWORD dwBytesRead = 0;
//读取文件并存入全局内存
BOOL bRead = ReadFile(hFile, pvData, dwFileSize, &dwBytesRead, NULL);
_ASSERTE(FALSE != bRead);
GlobalUnlock(hGlobal);
CloseHandle(hFile);
LPSTREAM pstm = NULL;
// 通过全局内存创建 IStream* 的指针
HRESULT hr = CreateStreamOnHGlobal(hGlobal, TRUE, &pstm);
_ASSERTE(SUCCEEDED(hr) && pstm);
//通过图形文件创建IPicture 对象 IPicture* gpPicture = NULL; if (gpPicture)
gpPicture->Release();
hr = OleLoadPicture(pstm, dwFileSize, FALSE, IID_IPicture, (LPVOID *)&gpPicture);
_ASSERTE(SUCCEEDED(hr) && gpPicture);
pstm->Release();
if (gpPicture == NULL)
return false; BOOL bResult = FALSE;
ILockBytes *Buffer = 0;
IStorage *pStorage = 0;
IStream *FileStream = 0;
BYTE *BufferBytes;
STATSTG BytesStatistics;
DWORD OutData;
long OutStream;
CFile BitmapFile; CFileException e;
double SkipFloat = 0;
DWORD ByteSkip = 0;
_ULARGE_INTEGER RealData; CreateILockBytesOnHGlobal(NULL, TRUE, &Buffer); // Create ILockBytes Buffer hr = ::StgCreateDocfileOnILockBytes(Buffer,
STGM_SHARE_EXCLUSIVE | STGM_CREATE | STGM_READWRITE, 0, &pStorage); hr = pStorage->CreateStream(L"PICTURE",
STGM_SHARE_EXCLUSIVE | STGM_CREATE | STGM_READWRITE, 0, 0, &FileStream); gpPicture->SaveAsFile(FileStream, TRUE, &OutStream); // Copy Data Stream
FileStream->Release();
pStorage->Release();
Buffer->Flush(); // Get Statistics For Final Size Of Byte Array
Buffer->Stat(&BytesStatistics, STATFLAG_NONAME); // Cut UnNeeded Data Coming From SaveAsFile() (Leave Only "Pure" Picture Data)
SkipFloat = (double(OutStream) / 512); // Must Be In a 512 Blocks...
if(SkipFloat > DWORD(SkipFloat)) ByteSkip = (DWORD)SkipFloat + 1;
else ByteSkip = (DWORD)SkipFloat;
ByteSkip = ByteSkip * 512; // Must Be In a 512 Blocks...
// Find Difference Between The Two Values
ByteSkip = (DWORD)(BytesStatistics.cbSize.QuadPart - ByteSkip); // Allocate Only The "Pure" Picture Data
RealData.LowPart = 0;
RealData.HighPart = 0;
RealData.QuadPart = ByteSkip;
BufferBytes = (BYTE*)malloc(OutStream);
if(BufferBytes == NULL)
{
Buffer->Release();
HWND hWnd = AfxGetApp()->GetMainWnd()->m_hWnd;
MessageBoxEx(hWnd, "Can not allocate enough memory\t", ERROR_TITLE, MB_OK | MB_ICONSTOP, LANG_ENGLISH);
} Buffer->ReadAt(RealData, BufferBytes, OutStream, &OutData); char file[100];
GetTempPath(MAX_PATH,file); //取得临时文件目录
strcat(file,"temp.bmp"); if(BitmapFile.Open(file, CFile::typeBinary | CFile::modeCreate | CFile::modeWrite, &e))
{
BitmapFile.Write(BufferBytes, OutData);
BitmapFile.Close();
bResult = TRUE;
}
else // Write File Failed...
{
TCHAR szCause[255];
e.GetErrorMessage(szCause, 255, NULL);
HWND hWnd = AfxGetApp()->GetMainWnd()->m_hWnd;
MessageBoxEx(hWnd, szCause, ERROR_TITLE, MB_OK | MB_ICONSTOP, LANG_ENGLISH);
bResult = FALSE;
}
Buffer->Release();
free(BufferBytes);
gpPicture->Release();
GlobalFree(hGlobal);
http://www.codeproject.com/bitmap/cximage.asp
非常方便的举例:
... convert from a format to another
CxImage image;
// bmp -> jpg
image.Load("image.bmp", CXIMAGE_FORMAT_BMP);
if (image.IsValid()){
if(!image.IsGrayScale()) image.IncreaseBpp(24);
image.SetJpegQuality(99);
image.Save("image.jpg",CXIMAGE_FORMAT_JPG);
}
// png -> tif
image.Load("image.png", CXIMAGE_FORMAT_PNG);
if (image.IsValid()){
image.Save("image.tif",CXIMAGE_FORMAT_TIF);
}
CxImage image;
// bmp -> jpg
image.Load("image.bmp", CXIMAGE_FORMAT_BMP);
if (image.IsValid()){
if(!image.IsGrayScale()) image.IncreaseBpp(24);
image.SetJpegQuality(99);
image.Save("image.jpg",CXIMAGE_FORMAT_JPG);
}
// png -> tif
image.Load("image.png", CXIMAGE_FORMAT_PNG);
if (image.IsValid()){
image.Save("image.tif",CXIMAGE_FORMAT_TIF);
}