jasmid - A Javascript MIDI file reader and synthesiser Originally presented at BarCamp London 8, 13-14 November 2010 Instructions: Open index.html in browser. Turn up volume. Click on link. Sound output is via the Mozilla Audio Data API, with a Flash fallback originally taken from dynamicaudio.js by Ben Firshman <https://github.com/bfirsh/dynamicaudio.js> and hacked around by me. The code: stream.js - helper library for reading a string as a stream of typed data midifile.js - parses the MIDI file format into a header and a list of tracks, each consisting of a list of event objects replayer.js - steps over the data structure generated by midifile.js and calls the appropriate operations on the synthesiser synth.js - audio synthesiser; generates waveforms according to tweakable parameters audio.js - passes the generated waveform to either the Audio Data API or the Flash fallback widget (da.swf) Limitations: * The only event types supported by replayer.js are note on, note off, tempo change and program change * There are currently only two instrument presets defined in synth.js - one for strings and a 'piano' one for everything else - and neither of them are particularly good (just a single volume-modulated sine wave). Matt Westcott <matt@west.co.tt> - @westdotcodottt - http://matt.west.co.tt/