npm install ccap

var ccap = require('ccap')

these three ways all will be ok:

var captcha = ccap();

var captcha = ccap(width, height, offset);

var captcha = ccap({

	width:256,//set width,default is 256

	height:60,//set height,default is 60

	offset:40,//set text spacing,default is 40

	quality:100,//set pic quality,default is 50

	generate:function(){//Custom the function to generate captcha text

	     //generate captcha text here

	     return text;//return the captcha text

	}

});

var captcha = ccap();

var ary = captcha.get();//ary[0] is captcha's text,ary[1] is captcha picture buffer.

var text = ary[0];

var buffer = ary[1];

var http = require('http');

var ccap = require('../')();//Instantiated ccap class

http.createServer(function (request, response) {

	if(request.url == '/favicon.ico')return response.end('');//Intercept request favicon.ico

	var ary = ccap.get();

	var txt = ary[0];

	var buf = ary[1];

	response.end(buf);

	console.log(txt);

}).listen(8124);

console.log('Server running at http://127.0.0.1:8124/');

The MIT License

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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:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
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WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.