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jacket-captcha

jacket-captcha

A captcha that develop by Jacket Chen..

Sample

The generated captcha image looks like this: alt tag

Usage

First, install jacket-captcha.

npm install jacket-captcha

jacket-captcha depend on node-canvas, install node-canvas you'll need Cairo. For system-specific installation view the Wiki.

You can quickly install the dependencies by using the command for your OS:

OS Command
OS X brew install pkg-config cairo libpng jpeg giflib
Ubuntu sudo apt-get install libcairo2-dev libjpeg8-dev libpango1.0-dev libgif-dev build-essential g++
Fedora sudo yum install cairo cairo-devel cairomm-devel libjpeg-turbo-devel pango pango-devel pangomm pangomm-devel giflib-devel
Solaris pkgin install cairo pkg-config xproto renderproto kbproto xextproto
Windows Instructions on wiki

El Capitan users: If you have recently updated to El Capitan and are experiencing trouble when compiling, run the following command: xcode-select --install. Read more about the problem on Stack Overflow.

After you sucessfully install jacket-captcha, use it in your node app:

// require library 
var captcha = require('jacket-captcha');
 
// configure and create a captcha image 
var captchaObj = captcha.config({
    width: 70,      // image's width 
    height: 35,     // image's height 
    lineNumber: 6,  // the number of lines that would be drawn into the image in case of prevent the program automatically discern the code on the image 
    charNumber: 4   // the length of code 
}).create();
 
// get the captcha code 
var code = captchaObj.code;
 
// get the base64 url of the captcha image 
var base64URL = captchaObj.base64URL;
 
// save the captcha image, you could specify the image's name and where to store it 
captchaObj.save({
  dirname: 'a/b/c',
  filename: 'captcha'
});
 
// Do something... 
 

API

require jacket-captcha will return a captcha instance.

Captcha#config(options)

Return: Object
This method will return the captcha instance.

options

Type: Object
The configuration of the captcha instance.

options.width

Type: Number
Config the width of the captcha image.

options.height

Type: Number
Config the height of the captcha image.

options.lineNumber

Type: Number
Config the number of lines that would be drawn into the image in case of prevent the program automatically discern the code on the image.

options.charNumber

Type: Number
Config the length of code.

Captcha#create()

Return: Object
Create a captcha image.
This method will return the captcha image instance.

Captcha#getCode()

Return: String
Get the captcha code.
This method will return the captcha code that generated by the method of Captcha#create().

Captcha#getBase64URL()

Return: String
Get the base64 url of the captcha image.
This mehod will return the base64 url of the captcha image that generated by the method of Captcha#create().

Captcha#save(options)

options

Type: Object
Specify the name of the saved image and where to store it.

options.dirname

Type: String
The directory where to store the image.

options.filename

Type: String
The name of the saved image.