qr ~main

QR Code for D

A self-contained QR Code generator library and CLI tool for the D programming language. No external dependencies required.

Generate QR Codes and save them as PNG, SVG, SVGZ, or PPM files, or display them directly in your terminal as ASCII art.

Based on Project Nayuki's implementation.

Library Usage

Add this library to your project using:

### Basic Example

import qr; QrCode("Hello, world!").saveAs("test.png");

/ same as above QrCode qrcode = "Hello, world!"; qrcode.saveAs("test.png"); /

You can set extra options for generator:

- `ecl`: Error Correction Level.
- `mask`: Mask pattern.
- `boostEcl`: Boost the error correction level (without increasing the size of the QR Code).

For example:

import qr; QrCode("Hello, world!", ecl: ErrorCorrectionLevel.HIGH).writeln; // Print QR Code to stdout

You can save the QR Code to a file (PNG, SVG, PPM) with some options:

 - `moduleSize`: Size of each module (pixel)
 - `padding`: Padding around the QR Code (in modules)
 - `foreground`: Foreground color (default: `#000000`)
 - `background`: Background color (default: `#FFFFFF`)

import qr; QrCode("Hello, world!").saveAs("test.png", moduleSize: 10, foreground: "#ff0000"); // Save a red QR Code as PNG

You can also access the raw QR Code data:

import qr; QrCode qrcode = "Hello, world!"; qrcode.size.writeln; // Print the size (number of modules per side) of the QR Code qrcode[0,0].writeln; // Print the module at position (0, 0) (true = black, false = white)

You can print QR Code as ASCII art:

import qr; QrCode("Hello, world!").writeln; // Print QR Code as ASCII art QrCode("Hello, world!").toString(dense: true).writeln; // Print QR Code as ASCII art, dense!

![immagine](https://github.com/user-attachments/assets/8eaff80d-f8eb-4751-9fdc-e22c87a5b0de)

## CLI Tool (qrc)

The project includes a versatile CLI tool called `qrc`.

### Help Message

Usage: qrc [options] "data"

Examples: qrc "hello world" # Print QR code to terminal qrc "hello world" -o qr.png # Save as PNG image qrc "data" -f dense # Use compact terminal representation qrc "secret" -f svg # Print QR code as SVG

Options: -o --output Output file (if omitted, results are printed to stdout) -f --format Output format: png, svg, svgz, ppm, ascii, dense -m --mask Mask pattern (0-7, or -1 for auto) -e --ecl Error correction level: low, mediumlow, mediumhigh, high

 --boost Boost error correction level (default: true). Use --boost=false to disable.

-p --padding Quiet zone size in modules (default: 2) -s --size Module size in pixels for images (default: 10)

--fg Foreground color hex (e.g. #000000) (default: #000000)
--bg Background color hex (e.g. #FFFFFF) (default: #FFFFFF)

-h --help This help information.

### Usage Examples

#### Terminal Output (ASCII)

Generate a standard ASCII QR code:

qrc "https://github.com/trikko/qr"

#### Compact Terminal Output (Dense)

Use the `dense` format for a more compact representation (uses Unicode half-block characters):

qrc "https://github.com/trikko/qr" -f dense

#### Save as Image

Save as a PNG with custom colors:

qrc "https://github.com/trikko/qr" -o logo.png --size 20 --fg "#1a2b3c" --bg "#f0f0f0"

## License

This project is licensed under the MIT License. See the `LICENSE` file for details.