qltool 0.2.4

Tool to print labels with Brother QL-700/QL-570 label printer

A wrapper around the excellent ql570.c by Asbjørn Sloth Tønnesen, Marc Juul and Luca Zimmermann.

Features

• Print text labels (1-3 lines)
• Print QR codes with text
• Print banners (text along paper length)
• Custom font sizes
• MQTT client for remote printing
• Preview before printing

Installation

Using uv (recommended):

uv pip install -e .

Or with pip:

pip3 install qltool

Usage

Standard Label Print

Print 1-3 lines of text:

# Preview only
uv run src/qltool/main.py "Line 1" "Line 2" "Line 3" --font-size 40

# Print with specific font size
uv run src/qltool/main.py "Hello World" "Second line" -p --font-size 55

QR Code Labels

# Generate and print QR code with text
uv run src/qltool/main.py "Item: 12345" "Location: Office" -q -p

# Use existing QR image
uv run src/qltool/main.py "Scan me" --qr /path/to/qrcode.png -p

Banner Mode (Text along paper length)

# Preview banner
uv run src/qltool/main.py "Long text banner" --banner --font-size 40

# Print banner
uv run src/qltool/main.py "STS Chvojkovice-Brod" --banner --font-size 40 -p

Command Options

• -p, --print - Send to printer (without this, shows preview)
• -q, --qr - Generate QR code
• --qr PATH - Use existing QR image
• --banner - Create banner (text along paper length)
• --font-size N - Set font size (default: 72)
• --width N - Set image width in pixels (default: 714 for 62mm tape)
• --gray N - Gray bias 0-100 (default: 50)
• -d, --device - Specify printer device (default: auto-detect /dev/usb/lp*)

MQTT Client

Run the MQTT client for remote printing:

qltool_client

Send print jobs via MQTT:

# Simple print
mosquitto_pub -t qltool/print -m "Hello World -p"

# With QR code
mosquitto_pub -t qltool/print -m "Inventory Item -q -p"

# Banner
mosquitto_pub -t qltool/print -m "Long banner text --banner -p"

Development

Run directly from source:

# Preview
uv run src/qltool/main.py "Test text" --font-size 40

# Print
uv run src/qltool/main.py "Test text" --font-size 40 -p

Requirements

• Brother QL-700 or QL-570 printer
• User must be in lp group for printer access
• Linux with USB lp device support (/dev/usb/lp*)

Org-mode Integration (Inventory)

For Emacs org-mode table integration:

;; Add to .emacs
(defun print-inventory-item ()
  "Print current org table row as label"
  (interactive)
  ;; Your implementation here
  )

Example table format:

The tool can extract ID and name fields to generate QR-coded inventory labels.

Credits

• ql570.c driver by Asbjørn Sloth Tønnesen, Marc Juul and Luca Zimmermann
• Built with Python, Click, Pillow, and OpenCV