How to show a big image on the iPhone (without overflowing the memory)?

Question

Hi,

I have an application that let's users view images. The user decides what images to use, so the size can range from 10x10 to 10000000x10000000 (I am exeggerating). All is well up to a certain size, when the image is bigger than the iPhone's memory. Quite understandably.

But how do I fix it? Is there a way to load only a portion of the image (I'm using an CATiledLayer, so I could load/release tile by tile).

Thanks in advance!

Answer 1

Unless you have an uncompressed image format it would be very hard to load the image in patches, you will have to provide the patches that the user would load, determine what portion of the image to show, and load the correct patches. There is an example for this "ScrollViewSuite" that demonstrate that technique. But this technique does require a preprocessing step.