BarcodeImageReader Class

Namespace: Meziantou.Framework.Imaging.Barcodes
Assembly: Meziantou.Framework.Imaging.Barcodes.dll
Package: Meziantou.Framework.Imaging.Barcodes 1.0.10
Source: BarcodeImageReader.cs
Available in package assets: net10.0net11.0

Provides methods to read the linear barcodes of an image: Code 39, Code 93, Code 128, GS1-128, EAN, UPC, Codabar, ITF and GS1 DataBar.

public static class BarcodeImageReader

Methods

Name	Description
ReadBarcodes(Image, BarcodeReadingOptions?, CancellationToken)	Reads the linear barcodes of an image.

ReadBarcodes(Image, BarcodeReadingOptions?, CancellationToken)

BarcodeImageReader.cs

Reads the linear barcodes of an image.

public static IReadOnlyList<BarcodeImageResult> ReadBarcodes(this Image image, BarcodeReadingOptions? options = null, CancellationToken cancellationToken = default)

Parameters

image Image: The image. For an animated image, its first frame is read.
options BarcodeReadingOptions?: The reading options, or null for the defaults.
cancellationToken CancellationToken: A token to cancel the reading.

Returns

IReadOnlyList<BarcodeImageResult> The barcodes found, each once; empty when there is none.

Exceptions

ArgumentNullException: image is null.
OperationCanceledException: cancellationToken was canceled.

Remarks

The reader is made for clean images: generated, printed or scanned barcodes, photographed straight on. Parallel scan lines cross the image horizontally, vertically and at 30°, 60°, 120° and 150°, and BarcodeDecoder.DecodeScanLines reads the barcodes they cross: a barcode turned by another angle is read when one of the lines crosses all its bars. Code 39, Codabar and ITF, which have no check character, must be crossed by two lines that agree. A transparent background reads as white.

A barcode needs its quiet zones and narrow bars of at least 2 pixels. The pixels are classified as dark or light with the Otsu threshold of the image, then with a local threshold (Sauvola) when no barcode is found.

Example

using var image = Barcode.CreateEan13("590123412345").ToImage(); // or Image.Load("product.jpg")

var results = image.ReadBarcodes();

var result = Assert.Single(results);
Assert.Equal((BarcodeType.Ean13, "5901234123457"), (result.Result.Type, result.Text));