KONAMI eAMUSEMENT Visual Verification Image Classifier

classify.js

#!/usr/bin/env node

/*
	Instruction

1. Download raw (100x100 png) image files.
2. Execute ./classify.js foo.png bar.png baz.png
3. The output is the concatenation of characters reperesenting classes of each images.
4. ...?
5. Profit!!!

*/

var fs = require('fs');

var data = (function(str){
	var obj = {};
	str.split(',').forEach(function(x){obj[x.slice(0, 8)] = x[8];});
	return obj;
})("0b194f96b,0c982f58t,0eb6b657t,159a50bdl,28219a6cs,2e5e5f2ds,2efead89g,379ef53dl,"
+ "40103a67l,41401bebb,42e289bcg,4934db3dg,5839f804s,58cd383bl,7aef48fcl,8882c122s,89b8fdf5b,"
+ "8d812abbb,8f84a3ddt,92165cbcg,94eef3c2s,9cec59dbb,9e0e9e67t,b0cd8626t,c103674dg,c907addeb,"
+ "cca180c5s,ccb8dd81l,de9e6e0ct,e109bd81g,e5c4d054g");

var hash = function(buffer){
	var value = 0x9ABC123F;
	var i;
	for(i=buffer.length-1; i>=0 && i%4 != 3; i--)
		value ^= buffer[i]<<((i%4)*8);
	for(i=0; i+3<buffer.length; i+=4)
		value ^= buffer.readUInt32LE(i, true);
	if(value < 0) value += 0x100000000;
	value = value.toString(16);
	while(value.length < 8) value = '0'+value;
	return value;
};

var classify = function(buffer){
	return data[hash(buffer)] || '_';
};

if(process.argv.length <= 2){
	console.error("Usage: ./classify.js file1.png file2.png ...");
}

console.log(process.argv.slice(2).map(function(f){
	return classify(fs.readFileSync(f));
}).join(''));