###MxMReader

A program which encodes MxM (Musical Exploration Machine) output data as activation matrices for use with the Emergent neural network modeling program.

###How it Works

Musical tokens are represented as 3 distinct arrays, or "matrices", as they are referred to often in the code. 1 array represents the pitch of the token, another represents its duration, and the final array represents the timbre of the particular "note".

###Pitch

Pitch is the simplest to represent, although this is likely due to the fact that (admittedly important) things such as scale and key are not currently taken into account. As of this writing, pitch information is encoded as one of twelve note values along the chromatic scale. Associated is a vibration frequency in hertz, although I have yet to make a real use for that. The BIG assumption here is that these are just encodings of specific frequencies along a certain spectrum that we deem to be important to music.

Example pitch encodings (where A is the base frequency of 440 hz):

the note C => 000100000000 the note A => 100000000000 the note F# or Gb => 000000000100

###Duration

Duration is a little bit trickier. It must be encoded so as to take into account fractions of beats as well as multiples. This is done with simple division. One half of the representation matrix stands for the numerator of a fraction, the other half stands for the denominator.

#####Side note A future implementation of the duration encoding function may want to recursively subdivide each half of the array, allowing more complex fractional notation and any possibility for a length, for example: 12/(2/3) = 12*(3/2) = 36/2 = 18 beats, or (1/2)/12 = 1/24 of a beat #####End of side note

So, on to examples. The matrix for now is set at a size 24, which means a numerator with a possible 12 options, and a denominator with the same. Keep in mind that there are mult- iple possibilities for any duration based on this model. Whole beats are always represented in the simplest way, with a denominator of 1.

Duration of 8 beats => 000000010000100000000000 Duration of .5 beats => 100000000000010000000000 Also a duration of .5 beats => 010000000000000100000000

###Timbre

As there are a limited number of timbre options, this seems to be pretty much a free choice as to how to encode it. So as to not have a huge array with a bunch of 0's and one 1, this is going to be encoded in binary. My current count says there are exactly 128 possibilities, which is awfully convenient, so, we represent this as an 7 bit array based on the location in the timbres array of our particular timbre.

Examples: "cello" = timbres(127) => 1111111 "gunshot" = timbres(51) => 0110011