Is it possible to do very basic image recognition to compare an image against a database of images(resource folder images or any web servers images if we have) and determine which image in the database is the best match? I don't need to do any processing of any of the images, but simply differentiate between a finite list of images.
Is it any open source code available ?
I would recommend using OpenCV if you simply want to compare images (i.e. decide if two images are the same).
Here is a similar question on SO:
iOS image comparison
I would also go about reading a little bit about what Core Image (the iOS image library) has to offer, before going about OpenCV or other 3rd party.
I hope this helps.