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.

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:

``bash
npm install persian-captcha-generator
`

Yarn:

`bash
yarn add persian-captcha-generator
`

Usage

$3

`typescript
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);
})();
`

$3

`typescript
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});
});
`

$3

Route handler:

`typescript
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

!num_white
!num_green
!num_yellow
!num_red
!alph
!both

License

MIT