zoom image in fix box

[m2jalali]

hi

i am trying to  design a game like  Close Up game(https://itunes.apple.com/us/app/close-up-pics-guess-whats/id632311326?mt=8)

how can i zoom image in the fixed box?

when i set sacle property ,it change width and Height image.

i want to  fix width and height when i change scale property.

and show like below image.

i see this link

http://phaser.io/examples/v2/display/round-pixels

,that code change size of image box. 

i need to scale my image in the fixed box .

please guide me thanks.