match image returned by iPhone's ALAsset with real image on computer

I want to store some data about an iOS photo and later on reference that photo when it gets synched to a computer.

However I can't work out how to identify it's the same photo. ALAsset doesn't seem to give me the original filename, and the metadata doesn't provide any ID such as the sequence number from the camera.

Does anyone know how to get around this? I could fingerprint the photo, but it's a lot of computation to do on an iOS device!

ideas so far:

somehow get the filename from ALAasset
somehow use the ALAsset URL in a way that I can read it on the computer
somehow save data associated with the original file that will make its way to the computer
somehow save data so that the saved version incorporates the original filename
use the timestamp plus some other data (fails for RAW)
fingerprint the first Mb or so
find a better metadata scanner

Note that raw is even worse - the iOS doesn't really extract any metadata from it at all.

ALAsset reference

Solution

u can use get bytes of an assest. that will give the orginal image. you cant get the name of the file. if you have found some other solution do share that.

Regards Ankur