node-png-histogram v0.0.1

node-png-histogram

Generates a histogram as an image given an array of values

var nph = require("node-png-histogram"),
	fs = require("fs");

var data = [0.61, 0.64, 0.68, 0.71, 0.71, 0.71, 0.74, 0.81, 0.88, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.9, 0.79, 0.68, 0.57, 0.46, 0.35, 0.24, 0.13, 0.02, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0.01, 0.12, 0.23, 0.34, 0.45, 0.56, 0.67, 0.78, 0.88, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.91, 0.9, 0.83, 0.76, 0.67, 0.56, 0.45, 0.35, 0.26, 0.17, 0.15, 0.15];

var nodePNGHistogram = new nph({data: data, mirror: true, width: 1800, height: 150, color: {r: 0, g: 0, b:0, a: 100}, pattern: true}).generatePNG(function (alldata) {
    fs.writeFile('out.png', alldata);
  });

Getting Started

This is a simple histogram generator, please refer to example.js for a use case

Install

$ npm install node-png-histogram

Options

• Width (int): The width of the output image
• Height (int): The height of the output image
• Data (Required): An array of numbers
• Padding: The padding (top-bottom) to be included. Must be a number between 0 - 1. ie: 0.1 will give you 10% padding
• Mirror (float): Mirrors the histogram over the x-axis so it looks more like a sound wave
• Color: an object containg RGBA values ie: {r: 0, g: 0, b:0, a: 100}
• Pattern (boolean): If on it adds horizantal stripes to the output

Screenshots

Simple histogram with no mirror, pattern, or padding

More complex histogram with mirror and pattern on