Bit.BbScanner 11.0.0-pre-11

Bit.BbScanner

A dependency-free, high performance barcode scanner for Blazor: QR Code, Micro QR, Data Matrix, PDF417, Aztec, MaxiCode, Code 128, Code 39, Code 93, Codabar, EAN-13, EAN-8, UPC-A, UPC-E (with their add-ons), ITF, GS1 DataBar (with its stacked forms), DataBar Limited and DataBar Expanded, from the camera or from still images. The decoding - luminance conversion, binarization, detection, Reed-Solomon correction and bit stream parsing - is written in C#. JavaScript only opens the camera and copies pixels - there is no barcode SDK or JavaScript scanner library underneath.

Quick start

dotnet add package Bit.BbScanner

@* _Imports.razor *@
@using Bit.BbScanner

No services to register and no stylesheet to reference: the package's Blazor initializer injects _content/Bit.BbScanner/bit-bbscanner.css automatically.

@rendermode InteractiveWebAssembly

<BbScanner Formats="BbBarcodeFormat.QrCode | BbBarcodeFormat.Ean13"
           Region="BbScanRegion.CenteredSquare(0.7)"
           OnScan="HandleScan"
           OnError="e => _error = e" />

@code {
    private BbScannerException? _error;

    private void HandleScan(BbBarcodeResult result)
        => Console.WriteLine($"{result.Format}: {result.Text}");
}

Camera scanning runs on Blazor WebAssembly - a standalone app, or the WebAssembly pages of a Blazor Web App - and needs a secure context (HTTPS or localhost). Publish that client compiled ahead of time (<RunAOTCompilation>true</RunAOTCompilation>): on Blazor's default interpreter a 640x480 frame took about 100 ms in Chromium on a desktop, compiled about 1 ms. The decoder itself runs anywhere .NET runs:

using var decoder = new BbBarcodeDecoder(BbScannerOptions.ForStillImages());
var result = decoder.Decode(rgbaPixels, width, height, BbPixelFormat.Rgba32);

Features

• Eighteen symbologies read to specification, checked against symbols written by an independent encoder; PDF417, Aztec, MaxiCode and Micro QR at any orientation.
• One copy per frame: frames reach managed memory through a [JSImport] memory view, with no JSON or base64.
• No garbage per frame: buffers, bit planes and detectors are reused, so an empty frame allocates nothing on the linear path.
• Misreads guarded against: check digits, guard patterns and repeated reads are verified before a value is reported.
• Camera selection, torch and zoom; still image scanning through a built-in file picker or DecodeImage.
• Scan regions, render fragment overlays and message templates, and theming through CSS custom properties.
• A labelled, keyboard-operable scanner that announces results and alerts failures, every text translatable through BbScannerTexts, with right-to-left, reduced motion and forced colours support, and an optional vibration or beep.
• A camera the phone ends when the page goes into the background is reopened when it returns; ReleaseCameraWhenHidden closes it whenever the page is hidden.
• .NET 8, 9 and 10.

For AI agents

The demo site hosts an MCP server at https://bbscanner.bitplatform.dev/mcp that answers from the shipped library: its API, its guide, its symbologies, a decode lab and the demo's working pages.

Documentation

The full guide - symbologies, the component's parameters, events and methods, still images, styling, the decoder outside Blazor, hosting models, errors and permissions, what it reads, performance and architecture - is in the BbScanner README. See it running at bbscanner.bitplatform.dev.