brother_ql

This is a crate to convert image data to the Raster Command binary data understood by Brother QL series label printers.

Looking for a CLI tool? Check out brother-label, a command-line application built on this library.

Features

• 📦 Compile to binary data - Convert images to raster command bytes that can be sent to the printer via USB, network, or saved to files
• 🔌 Direct USB printing - Print labels directly via USB connection with full status monitoring (also supported via a kernel connection)
• 📊 Status information - Read detailed printer status including errors, media type, and operational phase
• 🎨 Two-color printing - Support for red and black printing on compatible printer models
• 🏷️ Multiple media types - Support for continuous and die-cut labels in various widths

Supported Printers

See the list of supported printers in the main README.

Note: This crate is still work-in-progress and some bugs might still exist.

For more details, check the official Raster Command Reference (this one is for the 8xx series).

Installation

cargo add brother_ql

# Or with optional features:
cargo add brother_ql --features usb

Feature flags:

• usb - Enable USB printing support (requires libusb)
• serde - Enable serialization support

Examples

Printing via USB connection

Note: Requires the usb feature.

use brother_ql::{
    connection::{PrinterConnection, UsbConnection, UsbConnectionInfo},
    media::Media, printer::PrinterModel, printjob::PrintJobBuilder,
};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Create connection info for QL-820NWB
    let info = UsbConnectionInfo::from_model(PrinterModel::QL820NWB);
    // Open USB connection
    let mut connection = UsbConnection::open(info)?;
    // Read status from printer
    let _status = connection.get_status()?;
    // Create a print job
    let img = image::open("c62.png")?;
    let job = PrintJobBuilder::new(Media::C62)
        .add_label(img)
        // These are the defaults for the other options:
        // .high_dpi(false)
        // .compressed(false)
        // .quality_priority(true)
        // .cut_behavior(CutBehavior::CutEach) // default for continuous media
        .build()?;
    // Finally, print
    connection.print(job)?;
    Ok(())
}

Printing via kernel connection

Note: Works without any optional features. On Linux, you can use the kernel's USB printer driver (/dev/usb/lp0).

use brother_ql::{
    connection::{KernelConnection, PrinterConnection},
    media::Media, printjob::PrintJobBuilder,
};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Open kernel device connection
    let mut connection = KernelConnection::open("/dev/usb/lp0")?;
    // Create and print a job
    let img = image::open("c62.png")?;
    let job = PrintJobBuilder::new(Media::C62)
        .add_label(img)
        .build()?;
    connection.print(job)?;
    Ok(())
}

Compiling and saving a print job

Note: Works without any optional features.

use std::{fs::File, io::Write};
use brother_ql::{media::Media, printjob::PrintJobBuilder};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let img = image::open("c62.png")?;
    let job = PrintJobBuilder::new(Media::C62)
        .add_label(img)
        .build()?;
    let data = job.compile();
    let mut file = File::create("c62mm.bin")?;
    file.write_all(&data)?;
    Ok(())
}