Parsons Code

One relatively early attempt to create a simplified code for representing musical themes was proposed by Denys Parsons in his 1975 book The Directory of Tunes and Musical Themes. In this system, music notation is simplified tremendously by removing all rhythmic details and specific notes. All that is recorded are three possible values for each note in the theme, indicating the direction of pitch change in the melody: U for up, D for down, or R for repeat. The first note is typically indicated with an asterisk.

Therefore, to choose familiar example, the first eight notes of the first movement of Beethoven's symphony number 5 in C minor (figure 1) would be represented as:

*RRDURRD

Figure 1: Theme of the 1st movement of Beethoven's Symphony No. 5 in C minor (From www.all-about-beethoven.com)
Image beethoven5_1.png

The last movement of Beethoven's symphony number 9 begins with the famous ``Ode to Joy'' (see figure 2)

Figure 2: Theme of the 4th movement of Beethoven's Symphony No. 9 in D minor, ``Ode to Joy'' (From www.all-about-beethoven.com)
Image beethoven9_4.png

The first four bars of this famous theme can be represented in Parsons Code as:

*UURDDDDUURDR

As will be obvious to anyone familiar with musical notation, this simple representation strips away most of the information required to reproduce a melody. However, in practice this has been shown to be a reasonably effective way to form a query for a database of musical themes, especially when dealing with naïve users who require a ``forgiving'' system of representation that is conceptually simple and fault-tolerant [8].