我想在c ++中将属性从一个jpeg图像复制到另一个jpeg图像。由于我没有任何库,而且我正在使用Windows,我正在使用GDI +。 我的代码如下
void CopyJpegProperties(string targetImageName,string sourceImageName)
{
CLSID m_clsid;
EncoderParameters m_encoderParameters;
UINT size;
UINT count;
int quality=100;
GdiplusStartupInput gdiplusStartupInput;
ULONG_PTR m_gdiplusToken;
// start GDI+
GdiplusStartup(&m_gdiplusToken, &gdiplusStartupInput, NULL);
{
// we are processing images inside a block to make sure that all of objects are deleted when GDI is shutdown.
// read source image properties
std::wstring wcSourceImageName=StringTools::StringToWString(sourceImageName);
Gdiplus::Bitmap sourceBitmap(wcSourceImageName.c_str());
sourceBitmap.GetPropertySize(&size, &count);
PropertyItem* pPropBuffer =(PropertyItem*)malloc(size);
sourceBitmap.GetAllPropertyItems(size, count, pPropBuffer);
// write to target image
std::wstring wcTargetImageName=StringTools::StringToWString(targetImageName);
Gdiplus::Bitmap targetBitmap(wcTargetImageName.c_str());
for(int i=0; i<count; i++)
{
targetBitmap.SetPropertyItem(&pPropBuffer[i]);
}
JpegTools::GetEncoderClsid(L"image/jpeg", &m_clsid);
m_encoderParameters.Count = 1;
m_encoderParameters.Parameter[0].Guid = EncoderQuality;
m_encoderParameters.Parameter[0].Type = EncoderParameterValueTypeLong;
m_encoderParameters.Parameter[0].NumberOfValues = 1;
m_encoderParameters.Parameter[0].Value = &quality;
Status stat = targetBitmap.Save(wcTargetImageName.c_str(), &m_clsid, &m_encoderParameters);
if(stat != Ok)
{
throw exception("Error in saving");
}
}
GdiplusShutdown(m_gdiplusToken);
}
此函数失败,错误代码为7,win32error。
我认为问题在于,当我打开目标文件时,我无法写入它,因为它被open函数锁定。
我该如何解决?
有没有更好的方法在Windows中读取/写入图像属性?