On Tuesday, August 8, 2017 at 3:16:46 PM UTC+2, Alex Knauth wrote: > > On Aug 8, 2017, at 8:15 AM, Luis Sanjuán <luisj.sanj...@gmail.com> wrote: > > > > Hi, phillip > > > > As far as I'm concerned, professional musician too, I wrote a little app, > > just a prototype, using a similar representation of pitch classes and > > intervals for basic chord analysis. Since actual chords can be seen as > > sequences of intervals, its analysis can be reduced to determine the chord > > patterns actual chords match. This leads to at least all possible > > interpretations. Further work, some AI for sure, would be needed to select > > proper interpretations. Without that, though, a summary of possible matches > > cuold be as is useful for students in the first years of Harmony > > I've been trying to do something similar, representing chord-kinds as > sequences of intervals and matching the possible chord patterns to the notes. > > I've been basing it on the chord-labeling algorithm in a paper I found, > "Algorithms for Chordal Analysis" by Bryan Pardo and William P. Birmingham, > but there are a few situations where this doesn't label the correct chord. In > particular when there are something like short arpeggios in the harmony and > longer passing tones or suspensions in the melody, it gives more weight to > the passing tones and suspensions. > > Is that similar to the strategy you used? Is there any way to deal with > passing tones like this? > > Alex Knauth
Looks interesting! Mine, written in a couple of days, is much simpler. It just arranges chords to match chord patterns (what Pardo an Birmingham call templates, as I read) and labels them accordingly. First, it assumes chord boundaries are given, say, for instance, each arpeggio of Bach's Prelude I in das Wohltemperierte Klavier, and there is no attempt to score alternatives. The task in a real world scenario looks really demanding. Although I've never thought of it, for what I've skim-read I agree with P and B that, first, we need ways to determine chord boundaries, and secondly, algorithms to score possible interpretations. And, at first glance, it seems to me that both tasks cannot be completely isolated, since boundaries may depend on the interpretation. On the other hand, even chord patterns (which of them are suitable and the probability of its occurrence) may differ according to the historic and stylistic context, even by composer, as it is actually the case in real music. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.