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@craigtaub
Last active December 29, 2015 16:48
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Image screenshot and comparison tool
/*
Needs PhantomJS
uses Node.js File API
uses base64 encoding
event based on rendering image.
node modules:
JsDiff (https://github.com/kpdecker/jsdiff)
colors.js (https://github.com/brehaut/color-js)
imagemagick (node npm)
events (node npm)
keep in 1 place (node_modules)..then can do npm install <whatever as for>
npm install
-reads a package.json for dependencies
CAIRO (for imagediff):
sudo cp /opt/X11/lib/pkgconfig/* /usr/local/lib/pkgconfig/
*/
/////////////// CREATE BASE64
var Base64 = {
// private property
_keyStr : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
// public method for encoding
encode : function (input) {
var output = "";
var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
var i = 0;
input = Base64._utf8_encode(input);
while (i < input.length) {
chr1 = input.charCodeAt(i++);
chr2 = input.charCodeAt(i++);
chr3 = input.charCodeAt(i++);
enc1 = chr1 >> 2;
enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
enc4 = chr3 & 63;
if (isNaN(chr2)) {
enc3 = enc4 = 64;
} else if (isNaN(chr3)) {
enc4 = 64;
}
output = output +
this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) +
this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);
}
return output;
},
// public method for decoding
decode : function (input) {
var output = "";
var chr1, chr2, chr3;
var enc1, enc2, enc3, enc4;
var i = 0;
input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
while (i < input.length) {
enc1 = this._keyStr.indexOf(input.charAt(i++));
enc2 = this._keyStr.indexOf(input.charAt(i++));
enc3 = this._keyStr.indexOf(input.charAt(i++));
enc4 = this._keyStr.indexOf(input.charAt(i++));
chr1 = (enc1 << 2) | (enc2 >> 4);
chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
chr3 = ((enc3 & 3) << 6) | enc4;
output = output + String.fromCharCode(chr1);
if (enc3 != 64) {
output = output + String.fromCharCode(chr2);
}
if (enc4 != 64) {
output = output + String.fromCharCode(chr3);
}
}
output = Base64._utf8_decode(output);
return output;
},
// private method for UTF-8 encoding
_utf8_encode : function (string) {
string = string.replace(/\r\n/g,"\n");
var utftext = "";
for (var n = 0; n < string.length; n++) {
var c = string.charCodeAt(n);
if (c < 128) {
utftext += String.fromCharCode(c);
}
else if((c > 127) && (c < 2048)) {
utftext += String.fromCharCode((c >> 6) | 192);
utftext += String.fromCharCode((c & 63) | 128);
}
else {
utftext += String.fromCharCode((c >> 12) | 224);
utftext += String.fromCharCode(((c >> 6) & 63) | 128);
utftext += String.fromCharCode((c & 63) | 128);
}
}
return utftext;
},
// private method for UTF-8 decoding
_utf8_decode : function (utftext) {
var string = "";
var i = 0;
var c = c1 = c2 = 0;
while ( i < utftext.length ) {
c = utftext.charCodeAt(i);
if (c < 128) {
string += String.fromCharCode(c);
i++;
}
else if((c > 191) && (c < 224)) {
c2 = utftext.charCodeAt(i+1);
string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
i += 2;
}
else {
c2 = utftext.charCodeAt(i+1);
c3 = utftext.charCodeAt(i+2);
string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
i += 3;
}
}
return string;
},
grabFileContents : function(file) {
'use strict';
var fs = require('fs'),
system = require('system');
var content = '',
f = null;
try {
f = fs.open(file, "r");
content = f.read();
} catch (e) {
return false;
//console.log(e);
}
if (f) {
f.close();
}
return Base64.encode(content);
},
theComparison : function() {
/////////// COMPARE
var one = Base64.grabFileContents("screenshots/3.png");
if (one === false) {
console.log('first dosnt exist');
console.log('delete second now');
} else {
var two = Base64.grabFileContents("screenshots/4.png");
if (two === false) {
console.log('second doesnt exist')
} else {
console.log('comparison:', one === two);
/* IMAGE MAGICK
var im = require('imagemagick');
im.identify('screenshots/3.png', function(err, features){
if (err) throw err;
console.log(features);
// { format: 'JPEG', width: 3904, height: 2622, depth: 8 }
});
*/
//emitter, util
/*
var gm = require('gm');
gm('screenshots/3.png')
.resize(353, 257)
.autoOrient()
.write(writeStream, function (err) {
if (!err) console.log(' hooray! ');
});
*/
var imageDiff = require('imagediff');
console.log('END');
var three = imageDiff.diff("/Users/taubc01/Documents/cssregression/screenshots/4.png", "/Users/taubc01/Documents/cssregression/screenshots/3.png");
imageDiff.imageDataToPNG(three, "/Users/taubc01/Documents/cssregression/screenshots/file.diff.png");
console.log('DONE!!');
/*
Error: Cannot find module 'stream'
TRY:
-git clone js-imagediff
-git clone canvas
sudo gem install jasmine-headless-webkit
sudo port install qt4-mac
cd js-imagediff
make
FAIL
OR
sudo npm install -g imagediff
or (npm install canvas)
brew install cairo
-issue
https://github.com/LearnBoost/node-canvas/wiki/Installation---OSX
-issue
sudo port install cairo
#ln -s /opt/X11/lib/pkgconfig/cairo.pc /usr/local/lib/pkgconfig/cairo.pc
?
OR
git clone git://anongit.freedesktop.org/git/cairo cairo
?
OR
npm install stream
-installs into node_modules folder
- require(''); will check there by default
NEED CAIRO FOR CANVAS
NEED CANVAS FOR IMAGEDIFF
var three = imageDiff.diff(one, two);
imageDataToPNG(three, "file.diff");
/* DIFF
var JsDiff = require('/Users/craigtaub/Documents/PhantomCSS/jsdiff/diff.js');
var oldString = 'beep boop';
var newString = 'beep boob blah';
//console.log(newString);
var diff = JsDiff.diffChars(oldString, newString);
var array = [];
diff.forEach(function(part){
//console.log('1');
//string = part.value;
//array.push(string);
});
*/
/* COLORS.js
var colors = require('/Users/craigtaub/Documents/PhantomCSS/colors.js/colors.js');
var bigString = [];
diff.forEach(function(part){
var color = part.added ? 'green' :
part.removed ? 'red' : 'grey';
var string = "";
string = part.value;
//console.log(string . green , string . red);
//many colors 1 line
//need to pass colour as variable NOT string ??
if(color === 'green'){
//console.log(string . green);
}
if(color === 'grey'){
//console.log(string . green);
}
if(color === 'red'){
//console.log(string . green);
}
//console.log(string);
bigString.push(string);
//var bigString = bigString.concat(string);
//console.log(bigString);
});
console.log(bigString[0] . red ,bigString[1] . green ,bigString[2] . grey);
*/
}
}
}
}
/// CREATE SNAPSHOT
var page = require('webpage').create();
page.open('index.html', function () {
page.viewportSize = { width: 1000, height: 200 };
page.render('screenshots/4.png');
// var one = page.renderBase64();
// phantom.exit();
Base64.theComparison();
//END EVERYTHING
phantom.exit();
});
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