How to get part of image in iPhone

I need to perform to operations:

1. Allow user see all a开发者_开发知识库vailable albums and pick a picture from one of them.
2. Select specific area of the picture of a specific size.

I do know how to pick an image using UIImagePicker, but i can't see all albums and can't crop specific area.

Setting the sourceType on your UIImagePickerController to UIImagePickerControllerSourceTypePhotoLibrary allows for selecting from all the images on the device (I don't remember if they will be divided by album or displayed in one huge list).

You can have UIImagePickerController provide a cropping interface by setting allowsEditing.