Axtell's Notes: July 26

Constant Q is working! Really. It even can be graphed. Here's some proof:

a440 - Constant Q Transform

a440andOnePartial - Constant Q Transform

fade - Constant Q Transform

pretty - Constant Q Transform

These aren't scaled correctly as Constant Q is logarithmic and I have been using the FFT grapher so we could see if we were getting any points back. I would have a screenshot of Maple Leaf Rag to show you, but at the pace these were taking, it seemed like a 2-minute song would have taken around 7 hours. I'll be running it tonight so tomorrow morning we can see that.

We have written the most common kernel for the CQT (min. frequency = 16.352 Hz, max. frequency = 22050.0 Hz, bins per octave = 12, sample rate = 44100.0) to a text file so the computer doesn't have to re-calculate it each time. If those values are changed (min/max frequency and bins are changeable in the advanced menu and the sample rate is given by the sound file) the kernel is calculated, but not written to a file.

Tomorrow's to do list:
-Adding windowing functions to CQT
-Getting the CQT data into a logarithmic scale
-General clean-up and testing