DIRAC2 for real time pitch shifting and autotune?

Question

Has anyone implemented the DIRAC2 library from http://www.dspdimension.com/technology-licensing/dirac2-iphone/ for real time pitch correction on the iPhone? The library doesn't appear to support real time processing but perhaps someone has done it?

Thx

Answer 1

Confirmed from DSP Dimensions, that the current DIRAC2 library will not work in real time.

Answer 2

I integrated DIRAC2 into an iPhone app so I could modify the playback speed, and it does indeed work in real-time on an iPhone 4. I had to use the lowest possible settings to keep the CPU usage down, but it does play without any skips and I am able to change the playback speed seamlessly.

Running the same project on a 3GS device yielded lesser results - namely that the audio had enough skipping that it wasn't really usable. One caveat to this, though, is that I was running my test on the free version of DIRAC2 which only supports a 44100 sample rate, which is much higher than I need. If the pro version is used and you slash the sample rate down to 22050 or lower, it might work on a 3GS, but don't quote me on that.

Anything older than a 3GS has absolutely no chance of real-time playback.

Hope this helps.