Johnny-Five Arduino UNO Pixel Iterator RGB LED Code

controller.js

var five = require('johnny-five');
var keypress = require('keypress');
var gm = require('gm');
var board = new five.Board();
var fs = require('fs');
var PNG = require('pngjs').PNG;

function componentToHex(c) {
    var hex = c.toString(16);
    return hex.length == 1 ? "0" + hex : hex;
}

function rgbToHex(r, g, b) {
    return "#" + componentToHex(r) + componentToHex(g) + componentToHex(b);
}

board.on('ready', function() {
    // for my information
    (new five.Led(8)).strobe();

    var led = new five.Led.RGB({
        pins: {
            red: 11,
            green: 10,
            blue: 9
        }
    });


    fs.createReadStream('crazy.png')
        .pipe(new PNG({
            filterType: 4    
        }))
        .on('parsed', function() {
            var me = this;

            var i = 0;
            var j = 0;
            for (var y = 0; y < this.height; y++) {
                for (var x = 0; x < this.width; x++) {
                    if (i % 100 == 0) {
                        (function(j, x, y) {
                            setTimeout(function() {
                                var idx = (me.width * y + x) << 2;
                                // invert color
                                var r = me.data[idx];
                                var g = me.data[idx+1];
                                var b = me.data[idx+2];
                                // console.log(r, g, b);
                                var hex = rgbToHex(r, g, b);
                                console.log(j, ':', hex);
                                led.color(hex);
                            }, 70 * j);
                        })(j, x, y);
                        j++
                    }
                    i++;
                }
            }
            console.log('loop done');
        });

    // Expose to REPL
    this.repl.inject({
        led: led
    });

});