windows - QImage dithering quality -

We are currently using a commercial library for image rendering with Windows when images smaller than the original size to display monochrome images in size, the library measures gray images that can still be recognized most of them:

Now I tried the same with QT 4.8 application. Actually what has been called:

  QImage mimage; ... mImage.load (...); ... painter.dreams (painters, mimage, mimage.) ());  

Where the comic is smaller than mImage.rect (). That's why it does work well, but producing much less satisfying:

I have tried many renderHints (QPainter :: SmoothPixmapTransform, antialiasing, HighQualityAntialiasing) and the image

  mImage = mImage.convertToFormat (QImage :: Format_RGB32);  

QPainter :: SmoothPixmapTransform was looking to improve the output slightly (this is included in the screen shot).

Am I missing something?

How can the pictures of scarcity be displayed?

When it is possible

  painter.drawImage (paintRect , MImage, mImage.rect ());  

The painter simply reflects that pixel between each other when size is different. Which will be the second image

Using Scale manual

  QImage todraw = mImage.scaled (paintRect.size (), Qt :: IgnoreAspectRatio, Qt :: SmoothTransformation) ; ... painters Dihyme (Painteract, Tudra, MIMage.) ());  

You resize the events on the image calculation todraw only (to avoid scaling each color event) and you use it with the painter.