LaDiDa Demo from khush on Vimeo.

There’s no question iPhone/iPod touch development – really, just clever mobile development – has gotten a bit overhyped lately. But that’s all the more reason to do a round-up of genuinely interesting stories, real innovation happening on the platform. So, I’m clearing out my inbox with some of the more creative tools appearing recently on Apple’s mobile gadgets. There’s no better way to kick off today’s festivities than with this unusual “reverse karaoke” creation.

Sure, people may think they’re tone-deaf. But even the layperson has extraordinary powers of musical perception. So how could you train your iPhone to perceive and respond to music? That’s the question asked by LaDiDa for iPhone, the first of a new line of “intelligent” music applications for mobile devices. A “reverse karaoke” tool, the idea is to listen to singing and fake accompaniment, rather than having you sing along to canned backing tracks. Nothing is pre-programmed; everything is generated on the fly on the device.

It’ll even make up a Bollywood accompaniment to your singing:

LaDiDa Bollywood Duet from khush on Vimeo.

Of course, to me, it’s interesting not only what the iPhone is able to musically, but also what these algorithms are unable to make sound musical. Both reveal a whole lot about how we hear and conceptualize music. I think the team deserves real credit for making this fun, though, and on constrained hardware.

The app’s creator Khush follows in the footsteps of Smule in that it takes hard-core academic music research and uses mobile devices as a vessel for getting that tech in the hands (literally) of the general public. (See my interview with Smule founder and ChucK originator Dr. Ge Wang.)

Parag Chordia, developed at professor at the Georgia Institute of Technology and the gentleman you see in the video, spoke to CDM about what’s happening behind the scenes. He tells us about how this application was developed, and how the intelligent algorithms work (or at least try to work, as music analysis and auto-accompaniment remain at early stages).

First, an explanation of the app.