Image color palette extraction with node-canvas for node.js;
$ npm install palette
Palette's public API consists of a single function, the one returned by require(). This function accepts the canvas you wish to compute a color palette for, and an optional number of samples defaulting to 5.
The following example is taken from the ./test script, showing you how you may re-draw the palette onto the original canvas, however it is of course possible to save these values in a database etc.
var colors = palette(canvas, 10);
colors.forEach(function(color){
var r = color[0]
, g = color[1]
, b = color[2]
, val = r << 16 | g << 8 | b
, str = '#' + val.toString(16);
ctx.fillStyle = str;
ctx.fillRect(x += 31, canvas.height - 40, 30, 30);
});$ ./test examples/cat.jpg && open /tmp/out.png
(The MIT License)
Copyright (c) 2011 TJ Holowaychuk <tj@vision-media.ca>
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
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