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What is the best way to handle very high resolution images?

I am developing an application that should use images with a resolution higher (2000 x 2000) for the purposes of clarity of text.

I have a background image over which I need to show Overlay Images with the same resolution. The number of variable overlays, from 2 to 30.

Like loading an image using UIImage, 4 bytes are required for each pixel, so if one image has a resolution of 3000x3000, it will take up to 34 MB of memory, 15 MB for 2000 x 2000.

That's where the problem grows, the application crashes after uploading 4-5 images to 3GS and 11-13 images to iPhone 4.

Overlays should be placed exactly above the background image. They are similar to what we have in the overlays of Google Maps Overlays. This does not preclude partitioning, but makes the task relatively difficult.

How do I solve this problem?

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Certainly, you cannot immediately load the entire set of images into memory. You only need to load the visible part of the image data and unload the invisible part as quickly as possible.

If you want to solve this at the QuartzCore level, the CATiledLayerclass is just for this purpose.

Apple Reference: https://developer.apple.com/library/mac/#documentation/GraphicsImaging/Reference/CATiledLayer_class/Introduction/Introduction.html

Apple: https://developer.apple.com/library/mac/#samplecode/CALayerEssentials/Introduction/Intro.html#//apple_ref/doc/uid/DTS40008029

: http://red-glasses.com/index.php/tutorials/catiledlayer-how-to-use-it-how-it-works-what-it-does/

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, OpenGL . PVRTC, , , . CATiledLayer. .

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