Persian Captcha Generator

A library for generating customizable captchas with Persian numbers and alphabets. This library generates a captcha image with various options such as Persian numbers, alphabets, or both, and adds noise elements like random lines and dots for enhanced complexity.

Made with ❤ by Ali Piry

Features

• Generate captchas with:
  • Only Persian numbers
  • Only Persian alphabets
  • A mix of Persian numbers and alphabets
• Customizable:
  • Image size (width and height)
  • Font size and colors
  • Noise elements like lines and dots
• Outputs a PNG buffer and the text for verification

Installation

Npm:

npm install persian-captcha-generator

Yarn:

yarn add persian-captcha-generator

Usage

NodeJS

import fs from "fs";
import { persianCaptchaGenerator } from "persian-captcha-generator";

(async () => {
  const captcha = await persianCaptchaGenerator({
    length: 6,
    characterSet: "numbers",
    width: 300,
    height: 100,
    fontSize: 40,
    lineCount: 10,
    dotCount: 100,
    textColor: "#000000",
    backgroundColor: "#f8f9fa",
  });

  // Save the PNG buffer as a file
  fs.writeFileSync("captcha.png", captcha.imageBuffer);

  // Log the captcha text for validation
  console.log("Generated Captcha Text:", captcha.text);
})();

ExpressJS

import express from "express";
import { persianCaptchaGenerator } from "persian-captcha-generator";

const app = express();
const PORT = 3000;

app.get("/captcha", async (_req, res) => {
  try {
    const captcha = await persianCaptchaGenerator({
      width: 300,
      height: 100,
      length: 6,
      backgroundColor: "#ffffff",
      textColor: "#000000",
      fontSize: 44,
      lineCount: 8,
      dotCount: 50,
      characterSet: "both",
    });

    console.log("Generated Captcha Text:", captcha.text);

    res.setHeader("Content-Type", "image/png");
    res.send(captcha.imageBuffer);
  } catch (error) {
    console.error("Error generating captcha:", error);
    res.status(500).send("Failed to generate captcha");
  }
});

app.listen(PORT, () => {
  console.log(`Server is running at http://localhost:${PORT}`);
});

NextJS

Route handler:

import { NextResponse } from "next/server";
import { persianCaptchaGenerator } from "persian-captcha-generator";

export async function GET() {
  const captcha = await persianCaptchaGenerator({
    length: 6,
    characterSet: "numbers",
    width: 300,
    height: 100,
    fontSize: 40,
    lineCount: 10,
    dotCount: 100,
    textColor: "#000000",
    backgroundColor: "#f8f9fa",
  });

  const imageBuffer = Buffer.from(captcha.imageBuffer);

  return new NextResponse(imageBuffer, {
    headers: {
      "Content-Type": "image/png",
      "Content-Length": imageBuffer.length.toString(),
    },
  });
}

See full example here

Function API

The persianCaptchaGenerator function accepts the following options:

Parameter	Type	Default	Description
width	number	200	Width of the captcha image (in pixels).
height	number	80	Height of the captcha image (in pixels).
length	number	5	Number of characters in the captcha text.
backgroundColor	string	"#ffffff"	Background color of the captcha image (CSS color value).
textColor	string	"#000000"	Text color of the captcha characters (CSS color value).
fontSize	string	32	Font size of the captcha characters (in pixels).
lineCount	string	5	Number of random lines drawn over the captcha for obfuscation.
dotCount	string	50	Number of random noise dots added to the captcha image.
characterSet	numbers, alphabets, both	numbers	Choose the type of characters in the captcha: Persian numbers, alphabets, or both.

Output

The persianCaptchaGenerator function returns an object with the following properties:

Property	Type	Description
text	string	The randomly generated captcha text (for validation).
imageBuffer	Buffer	The PNG image buffer of the generated captcha.

Sample images

License

MIT