Getting movie URL from UIImagepickerController

When I shoot a video using UIImagepickerController, the movie url which I receive from imagePickerController:didFinishPickingMediaWithInfo: and the url when I receive from the same video after saving to c开发者_如何学Camera roll are different. Can anyone explain why this so?

Many Thanks, Naveen

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All media data within device are stored in Assets Library. You haven't raw access to this storage. iOS creates a temporary copy of movie which you want to use and store it into file accessible from your App.

After movie capturing you get back the temporary path to movie within your device file system. You need to save this file into your assets library (camera roll).

After movie choosing from library you get back the path to copy of compressed movie in device file system and url to assets library.