A Python package to control Brother QL label printers. It implements the raster language of those printers and allows you to send instruction files to your printer. In more details, the following is possible with this package:
- Create raster language files for the Brother label printers. They can be created from image files or programmatically in your own Python script.
- Print raster instruction files with your Brother label printer via different backends:
- pyusb (works cross-platform)
- network (works cross-platform for WiFi/Ethernet-enabled printers)
- linux_kernel (works on Linux only; uses the /dev/usb/lp0 device handles)
The following printers are claimed to be supported (✓ means verified by the author or by contributors):
- QL-500 (✓), QL-550 (✓), QL-560, QL-570 (✓), QL-580N, QL-650TD, QL-700 (✓), QL-710W (✓), QL-720NW (✓), QL-800, QL-810W, QL-820NWB, QL-1050, and QL-1060N.
The new QL-800 series can print labels with two colors (black and red). Printing in red is not yet supported by this package. If you want to have it supported, you may provide such a printer to the package author and ask him to add support for it.
The special feature of this package is that no printer driver is required for it to work. This software bypasses the whole printing system including printer drivers and directly talks to your label printer instead. This means that even though Brother doesn't offer a driver for the Raspberry Pi (running Linux on ARM) you can print nicely using this software. And even if there are drivers for your operating system, many programs have difficulties to set the page sizes and margins for the labels correctly. If you want to print with high precision (which is important for barcodes for example), you rather want to have control about every single pixel to be printed. This is where brother_ql comes into the game.
brother_ql is available from PyPI with pip:
pip install brother_ql
# or to upgrade to a newer release:
pip install --upgrade brother_ql
Alternatively, you can install the latest development version from Github using:
pip install --upgrade https://github.com/pklaus/brother_ql/archive/master.zip
This package was mainly created for use with Python 3. The essential functionality, however, will also work with Python 2: the creation of label files.
The main user interface of this package are its command line tools. You can also use its functionality from your own Python code (yet, there is no dedicated API documentation). The following sections show how to use the most important CLI tools.
The command line tool brother_ql_create is possibly the most important piece of software in this package.
It allows you to create a new instruction file in the label printers' raster language:
brother_ql_create --model QL-500 ./720x300_monochrome.png > 720x300_monochrome.bin
If you want to find out about its options, just call the tool with --help:
brother_ql_create --help
giving:
usage: brother_ql_create [-h] [--model MODEL] [--label-size LABEL_SIZE]
[--rotate {0,90,180,270}] [--threshold THRESHOLD]
[--no-cut] [--loglevel LOGLEVEL]
image [outfile]
positional arguments:
image The image file to create a label from.
outfile The file to write the instructions to. Defaults to
stdout.
optional arguments:
-h, --help show this help message and exit
--model MODEL, -m MODEL
The printer model to use. Check available ones with
`brother_ql_info list-models`.
--label-size LABEL_SIZE, -s LABEL_SIZE
The label size (and kind) to use. Check available ones
with `brother_ql_info list-label-sizes`.
--rotate {0,90,180,270}, -r {0,90,180,270}
Rotate the image (counterclock-wise) by this amount of
degrees.
--threshold THRESHOLD, -t THRESHOLD
The threshold value (in percent) to discriminate
between black and white pixels.
--no-cut Don't cut the tape after printing the label.
--loglevel LOGLEVEL Set to DEBUG for verbose debugging output to stderr.
The image argument should be a PNG/GIF/JPEG image file.
Here is the output of brother_ql_info list-label-sizes listing the available options for --label-size:
Supported label sizes:
Name Printable px Description
12 106 (12 mm endless)
29 306 (29 mm endless)
38 413 (38 mm endless)
50 554 (50 mm endless)
54 590 (54 mm endless)
62 696 (62 mm endless)
102 1164 (102 mm endless)
17x54 165 x 566 (17 x 54 mm^2)
17x87 165 x 956 (17 x 87 mm^2)
23x23 202 x 202 (23 x 23 mm^2)
29x42 306 x 425 (29 x 42 mm^2)
29x90 306 x 991 (29 x 90 mm^2)
39x90 413 x 991 (38 x 90 mm^2)
39x48 425 x 495 (39 x 48 mm^2)
52x29 578 x 271 (52 x 29 mm^2)
62x29 696 x 271 (62 x 29 mm^2)
62x100 696 x 1109 (62 x 100 mm^2)
102x51 1164 x 526 (102 x 51 mm^2)
102x152 1164 x 1660 (102 x 152 mm^2)
d12 94 x 94 (12 mm diameter, round)
d24 236 x 236 (24 mm diameter, round)
d58 618 x 618 (58 mm diameter, round)
Pro Tip™: For the best results, use image files with the matching pixel dimensions. Die-cut labels have to be in the exact pixel dimensions stated above. For endless label rolls, you can provide image files with a pixel width as stated above. If you provide a file with different dimensions when creating an endless label file, it will be scaled to fit the width.
Some notes:
Currently, the brother_ql_create tool doesn't support the 600x300 dpi mode supported by some printers.
The output will always use the 300dpix300dpi mode with the high quality preference set.
Once you have a Brother QL instruction file, you can send it to the printer like this:
cat my_label.bin > /dev/usb/lp1
Be sure to have permission to write to the device (usually adding yourself to the lp group is sufficient.
Or via network (if you have a LAN/WLAN enabled Brother QL):
nc 192.168.0.23 9100 < my_label.bin
You can also use the tool brother_ql_print (Py3 only) to send the instructions to your printer:
brother_ql_print 720x151_monochrome.bin /dev/usb/lp0
# or
brother_ql_print --backend network 720x151_monochrome.bin tcp://192.168.0.23:9100
# or (requires PyUSB: `pip install pyusb`)
brother_ql_print 720x151_monochrome.bin usb://0x04f9:0x2015
If your printer has problems printing the instructions file, it may blink its LED (green or red) depending on the model. This can have many reasons, eg.:
- The selected label doesn't match.
- End of paper.
- Unsupported opcode (wrong
--modelwhen usingbrother_ql_create?)
More info on how to debug difficult situations is to be found in the DEBUG doc.
- The source code and issue tracker of this package is to be found on Github: pklaus/brother_ql.
- The package is also to be found on PyPI: brother_ql.