Display part of image on a smaller QGraphicsItem

[biplab.project]

Hi,

I want to display an image on a smaller QGraphicsItem which has scrollbar.
While scrolling I am supposed to scroll the image.
But though the QGraphicsItem is samller and it is parent item of the image(QGraphicsPixmapItem), it is displaying the whole image.

Please find attached source code and snapshot.

Waiting for your help.

-Biplab