Magick++ Bitmap::GetThumbnailImage() 块文件，无法删除它

Question

各位程序员大家好。

首先我的 C/C++ 经验只有 5 周。（我目前是一名实习生，通常在我的实际工作中与 Java 一起工作）

我正在开发一个读取 .tif 文件并将其显示给用户的应用程序。用户查看完图像后，应将其关闭并从硬盘中删除。

问题是我无法在关闭图像后将其删除。我认为图像处理仍然是运行并且拒绝我的程序删除文件。

我猜 Gdiplus 以某种方式保持文件打开，即使我在位图上使用了 delete pCloneBmp;。有没有人有想法或尝试过与 Gdiplus 类似的东西？

我试过这段代码来删除文件（在下一个代码块中解释）：

delete pCloneBmp;
delete gdiZoomedLoaded;
delete gdiOrgLoaded;
DeleteObject( bmpLoaded );
remove( filenames.at( 0 ).c_str( ) );
WORD error = GetLastError( ); 
// error codes:
// 0 == Success
// 32 == The process cannot access the file because it is being used by another process.

这是我尝试做的：

// This is how I call the function.
scale_image( (Gdiplus::Bitmap*)gdiOrgLoaded , x_bmp , y_bmp , org_width_bmp , org_height_bmp , scale_bmp );

// vvv Function definition vvv
HBITMAP scale_image( Gdiplus::Bitmap *old_bmp , int x , int y , int width ,  int height , float scale )
{
HBITMAP result = NULL;
int newWidth = width * scale;
int newHeight = height * scale;

Gdiplus::RectF bmpRect( 0 , 0 , newWidth , newHeight );
Gdiplus::Bitmap *pCloneBmp = old_bmp->Clone( 0 , 0 , width , height , old_bmp->GetPixelFormat() );

// If I run the deletion code here the error code is 0
// and the file gets deleted

// vvv It seems that this line causes the problem vvv
pCloneBmp = ( Gdiplus::Bitmap* )pCloneBmp->GetThumbnailImage( newWidth , newHeight );

// If I run the deletion code here the error code is 32
// and the file won't be deleted

Gdiplus::Graphics *pGraphics = Gdiplus::Graphics::FromImage( pCloneBmp );
pGraphics->DrawImage( pCloneBmp , bmpRect , 0 , 0 , newWidth , newHeight , Gdiplus::UnitPixel );

if ( pCloneBmp )
{
    pCloneBmp->GetHBITMAP( Gdiplus::Color( 255 , 255 , 255 ) , &result );
}

delete( gdiZoomedLoaded );

gdiZoomedLoaded = pCloneBmp;

delete pGraphics;

return result;
}

非常感谢任何帮助:-)

编辑： 这是我加载图片的方式

gdiOrgLoaded = Gdiplus::Image::FromFile( pFilePath , false );
gdiZoomedLoaded = Gdiplus::Bitmap::FromFile( pFilePath , false );

HBITMAP result; // <-- This is bmpLoaded
gdiZoomedLoaded->GetHBITMAP( Gdiplus::Color( 255 , 255 , 255 ) , &result );

Answer 1

所以我确实弄明白了。正如@HansPassant 所建议的那样，这确实是一些内存泄漏。

这是我现在的工作职能。我也设法缩短了很多。

HBITMAP scale_image( Gdiplus::Bitmap *old_bmp , int x , int y , int width , int height , float scale )
{
HBITMAP result = NULL;
int newWidth = width * scale;
int newHeight = height * scale;

Gdiplus::Bitmap* newBitmap = new Gdiplus::Bitmap( newWidth , newHeight , old_bmp->GetPixelFormat( ) );
Gdiplus::Graphics *pGraphics = Gdiplus::Graphics::FromImage( newBitmap );
pGraphics->DrawImage( old_bmp , 0 , 0 , newWidth , newHeight );

delete( gdiZoomedLoaded );

gdiZoomedLoaded = newBitmap;

delete pGraphics;

return result;
}

Magick++ Bitmap::GetThumbnailImage() 块文件，无法删除它

Magick++ Bitmap::GetThumbnailImage() blocks file, unable to delete it

c++

winapi

gdi+