I am developing an app which require it to save .mp3 files(extension already changed) on sdcard. I want to encrypt those files so that it cannot be played directly just by changing extension. I have used AES/ECB and conceal from facebook .From several attempts it can be inferred that conceal is much efficient than AES/ECB. Is there any other algorithm which is efficient than these algorithms to encrypt/decrypt files not more than 15 mb.
Any help ll be highly appreciated.