image-filter-contrast/sandbox/sandbox.js

Small library to apply a contrast transformation to a image

var imageFilterCore = require('image-filter-core');
var imageContrast = require('../src/index');

function applyResults(selector, canvas, context, src) {
    var target = document.querySelectorAll(selector)[0];
    var image = document.createElement('img');
    image.setAttribute('src', imageFilterCore.convertImageDataToCanvasURL(src));
    target.appendChild(image);
}

window.onload = function () {
    var img = new Image;
    img.onload = function () {
        var canvas = document.createElement('canvas');
        canvas.width = img.width;
        canvas.height = img.height;
        var context = canvas.getContext('2d');
        context.drawImage(img, 0, 0);

        var data = context.getImageData(0, 0, img.width, img.height);

        imageContrast(data, { contrast: 30 })
            .then(function (results) {
                applyResults('#target-1', canvas, context, results);
            });

        imageContrast(data, { contrast: 70 })
            .then(function (results) {
                applyResults('#target-2', canvas, context, results);
            });
    };

    img.src = 'dummy.jpg';
};