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Library for generating 16mm optical soundtracks with Processing.

Install library by downloading library as .zip, uncompressing and placing SoundtrackOptical in your Processing library directory. Note: When extracting the .zip, the folder may be named "SoundtrackOptical-master" and should be renamed "SoundtrackOptical" before installing. Start up (or restart) Processing to use this library in a sketch.

Supports mono audio only (at the moment, feel free to contribute).

Draws various kinds of 16mm soundtracks. Read about them here..

Example Usage

import processing.sound.*;
import soundtrack.optical.*;

SoundtrackOptical soundtrack;

String soundtrackFile = "../../data/barking.wav";
int dpi = 2400;
float volume = 1.0;
String type = "dual variable area";
String pitch = "long";
boolean positive = true;

void setup() {
  size(213, 620, P2D);
  soundtrack = new SoundtrackOptical(this, soundtrackFile, dpi, volume, type, pitch, positive);

void draw () {
  soundtrack.draw(0, 0);

Alternate usages

Use the frame(int x, int y, int frameNumber) method to draw specific frames--used for laying out multiple frames of soundtrack on a single screen.

void draw () {
    soundtrack.frame(0, 0, frameCount);

Use the buffer(int frameNumber) method to return the internal PGraphics object that contains the specific frame of soundtrack data specified by the frameNumber. You can then draw onto the canvas, address the pixels directly, or as in the provided BufferExample.pde assign the image data to a PImage to be manipulated using the built-in transformation methods.

void draw () {
    PGraphics soundtrackBuffer = soundtrack.buffer(frameCount);
    image(soundtrackBuffer, 0, 0);