More updates to BigGUI today and a few to FFTGUI. First change is in FFTGUI. The function that gets the frequency of the point under the mouse and draws it next to the mouse now draws the note of that point under the frequency. I also added both those features to BigGUI's peak graph. After getting the updated NoteFinder and PeakData from Tayloe, I used threenotes.wav to test the notes by the mouse and they were all very close to correct.
We figured out that 512 is too small of a sample size to get an accurate sample. We are now using 1025 (one quarter of a second if the file has a 4.4 sampling rate.) I took some photos of the same file at 512, 1028, and 2048 samples to show the difference (All FFTS are at .2 seconds):
They show that a larger sample size gets rid of a lot of noise, gets louder peaks and more specific points. It also speeds up the program quite a bit.
I then fixed my algorithms that determined the color for each peak. The Hamming and Hanning windows return much quieter peaks (always under one) they were too small to effect the algorithm I had, so they didn't use shades at all, but five different colors (red, yellow, green, blue, magenta) I added a multiplier so they now use the full spectrum. The quietest peaks now graph as purple (rather than magenta) because magenta stood out and looked like a very loud peak when it was really the quietest.
All of the afternoon was spent on setting up an x-axis zoom for the peak graph. There is a scrollbar so that any part of the file can be zoomed in on (tomorrow I'll be adding this feature to the y-axis of the peak graph and FFTGUI.) It cuts off the last data point or two and the numbers on the axis don't change with the scroll, but I hope to get both of those problems fixed tomorrow.
I'm working on one algorithm that takes any range of amplitudes and plots them using the color spectrum so I don't need three different blocks of code (one for Hamming, one for Hanning, and one for Bartlett and un-windowed since they are so similar) So far, if often tries to make colors with number greater than 255.
Tomorrow more BigGUI and FFTGUI work and moving on to look at generating rhythm using some spectral tools.
Sample Size Comparison Using threenotes.wav
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