BrotherRaster.Skia 0.1.0

BrotherRaster

Print to Brother QL and P-touch label printers on the network from .NET, without Brother's driver or SDK.

• Raster encoders for the QL-800 series (QL-800, QL-810W, QL-820NWB: DK rolls, including two-color black/red) and the PT-E550W / PT-P750W / PT-P710BT (TZe tape, 3.5 to 24 mm).
• Delivery that does not leave a printer hung. Jobs go over raw TCP 9100. The transport waits for the printer to close the connection, which it does only after reading the whole job.
• Status over SNMP, including Brother's 32-byte status block: the model, and the loaded media's type and width. Neither family answers a status request on port 9100.
• A dispatcher that reads status, retries only jobs that never connected, and never sends one job twice.
• No dependencies in the core package. BrotherRaster.Skia adds drawing and PNG helpers, and BrotherRaster.Cli is a command-line tool.

The encoders are written from Brother's Raster Command Reference documents. The QL encoder is tested byte for byte against brother_ql 0.9.4. brother_ql runs as a black box in tools/brother-ql-oracle, and none of its code is in this library.

Packages

On Linux, add SkiaSharp.NativeAssets.Linux.NoDependencies (or another native assets package) next to BrotherRaster.Skia.

Printing a dated sticker on a P-touch

using BrotherRaster.Printing;
using BrotherRaster.Pt;
using BrotherRaster.Skia;
using BrotherRaster.Status;
using SkiaSharp;

var tape = PtTape.TZe12;
using var canvas = LabelCanvas.ForPt(tape, lengthDots: 300);   // 300 dots at 180 dpi = 42 mm
LabelText.DrawFitted(canvas.Canvas, new SKRect(6, 6, canvas.Width - 6, canvas.Height - 6),
    ["CAL 2026-10-21", "DUE 2027-10-21"]);

var job = PtRasterEncoder.Encode(canvas.ToLabel(), new PtRasterOptions { Tape = tape });

var host = "192.168.1.45";
var dispatcher = new LabelDispatcher(
    new RawTcpTransport(new RawTcpTransportOptions { Host = host }),
    new BrotherSnmpStatusSource(host) { ExpectedWidthMm = tape.WidthMm });
var outcome = await dispatcher.DispatchAsync(job);
Console.WriteLine($"{outcome.Result}: {outcome.Message}");

A QL label works the same way with LabelCanvas.ForQl(QlMedia.Continuous62, lengthDots) and QlRasterEncoder.Encode(label, new QlRasterOptions { Media = QlMedia.Continuous62 }).

Which way round

• QL: the bitmap is the label as read with the tape coming out top first. Its width is the roll's PrintableDots (696 on 62 mm) at 300 dpi, and its height is the length.
• P-touch: the bitmap is the label as read along the tape. Its height is the tape's PrintablePins (70 on 12 mm) at 180 dpi, and its width is the length (at 360 dpi with HighResolution).

The command-line tool

dotnet tool install -g BrotherRaster.Cli
brother-raster status 192.168.1.45
brother-raster text 192.168.1.45 "CAL 2026-10-21" "DUE 2027-10-21"
brother-raster print 192.168.1.50 label.png --ql 62mm
brother-raster pattern - --pt 24mm --out job.bin --png preview.png    # no printer needed
brother-raster decode job.bin --png preview.png

With no --ql or --pt, the tool asks the printer what is loaded.

Printer setup

• Command Mode must be Raster (web page → Printer Settings → Device Settings). New printers often ship in P-touch Template mode, and in that mode raster jobs print nothing. On some units the settings pages need the admin password printed on the printer's label.
• SNMP v1 with community public must be on for status. It is on by default.
• Never resend a job the printer accepted. A QL-810W with the cover open or no media, and a PT-P750W with the cover open, hold the job and print it once the fault is cleared, so resending gives two labels. Set LabelDispatchOptions.PrinterHoldsJobsOnFault = false to send nothing to a faulted printer.
• Use the right job for the roll. On a QL-8xx, a one-color job on the DK-22251 black/red roll (or a two-color job on plain tape) leaves the printer in ERROR with the red light blinking. Only switching it off and on clears that, and the job is lost. Send black/red rolls TwoColor = true.

See docs/hardware.md for what has been verified on which printer.

What has been verified

Rolls and tapes not marked as verified come from the reference tables. Please report what you find.

License

MIT. BrotherRaster.Skia embeds IBM Plex Sans Bold under the SIL Open Font License 1.1 (OFL-IBMPlex.txt). Brother, P-touch and the model names are trademarks of Brother Industries, Ltd. This project is not affiliated with Brother.