Spent the morning looking up information on scales and analysis programs. The just vs. equal temperamant issue of scales is interesting. Basically, in just temperament, scales are tuned based on one note, relative to that pitch, and each note as a slight variation based on what key it's in. Equal temperament sets a default pitch for each note, all relative, which leads to it being slightly worse than any given just tuning, but better at going to other keys with no need to re-tune. Due to the way NoteFinder works in ranges around equal temperament pitches, it should be accurate for instruments tuned that way (namely pianos), but, since it works in ranges around those pitches, it should also suffice for equal temperament pieces (like vocal groups).
Also read a lot about the mir group's various projects, which were linked from the main summer page. They talk a lot about different analysis programs, how they can find the genre or the beats or the scale, but don't say a lot about the actual analysis involved. I played with the online versions of the programs and downloaded a bit of the code, but so far I haven't found out much, except they use FFTs in some fashion. I couldn't download the proper programs, because admin passwords D:
This afternoon, I realized that, when the notes were graphed, they appeared sequentially, with no regard to what sample they came from. Axtell and I managed to make the frequencies be packeted, so we've gotten rid of the slanty lines, and replaced them with linear lines. I also did a comparative analysis on a song, showing the difference between no window (the upper) and Hanning window (the lower). It's pretty clear that the windowing gets rid of noise, but also a lot of quieter data. (For reference, the song was "My Freeze Ray" from Dr. Horrible's Sing-a-long Blog. )
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