UIImage allocates more memory

In my viewcontroller i created开发者_JAVA技巧 a UIImageView and assigned a image in the Interface Builder. While checking on instruments i have allocation of malloc of 600kb and the responsible library is ImageIO_Malloc. But the size of my image is 37kb. I dont know why it allocates 600kb.

I have also tried with the code by assigning UIImage imageNamed. Still no good.

Do you people have any idea on that.

600 kB is really not much to allocate for a image. Your 37 kB is probably just the size of the compressed image file. However when that image needs to be displayed the image view needs to allocate back buffering of it so it can be represented in an uncompressed format internally.

An image with dimensions of 640x480 pixels will result in 300.000 pixels, each of which needs and R, G, B, and possible alpha value - meaning 3-4 bytes per pixel. So you can easily see allocations in the order og 600 kB for even fairly small images.