QRBarcodeReadOptions Class

Summary

Contains extra options to use when reading QR barcodes.

Syntax

Objective-C

C++/CLI

Java

Python

[SerializableAttribute()] 
public class QRBarcodeReadOptions : BarcodeReadOptions

@interface LTQRBarcodeReadOptions : LTBarcodeReadOptions

public class QRBarcodeReadOptions extends BarcodeReadOptions

[TypeConverterAttribute()] 
[SerializableAttribute()] 
public ref class QRBarcodeReadOptions : public BarcodeReadOptions, System.ICloneable

class QRBarcodeReadOptions(BarcodeReadOptions):

Remarks

The QRBarcodeReadOptions class is used to control the options when reading QR barcodes using LEADTOOLS. Set the options in two ways:

The BarcodeReader class contains default options for each barcode symbology (or group of common symbologies). These options can be retrieved using the BarcodeReader.GetDefaultOptions method, passing BarcodeSymbology.QR. Change the members of the returned QRBarcodeReadOptions by casting it from BarcodeReadOptions to QRBarcodeReadOptions.

You can also create an instance of the QRBarcodeReadOptions class and use it directly in the BarcodeReader.ReadBarcode and BarcodeReader.ReadBarcodes methods that accept a single or array of options as an input parameter.

The base BarcodeReadOptions contains the following members and features:

Member	Description
BarcodeReadOptions.ForeColor	Controls the barcode foreground color (color of the bars or symbols) to use when reading a barcode from a colored image.
BarcodeReadOptions.BackColor	Controls the barcode background color (color of the spaces) to use when reading a barcode from a colored image.
BarcodeReadOptions.Load and BarcodeReadOptions.Save	Can be used to save or load the options to/from an XML file or stream.
BarcodeReadOptions.GetSupportedSymbologies	This class overrides the base class method to return an array containing the following symbologies: BarcodeSymbology.QR

In addition to the features and members, the QRBarcodeReadOptions contains these QR barcodes specific features:

Member	Description
EnableDoublePass	Enable internal auto preprocessing of the image data if no QR barcode was found.
EnableDoublePassIfSuccess	Enable internal auto preprocessing of the image data even if some QR barcodes were found.
EnablePreprocessing	Enable applying auto segmentation and deep auto pre-processing to the image then re-scanning if no barcodes of this symbology are found.

Example

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.Barcode; 
using Leadtools.ImageProcessing; 
 
 
public void QRBarcode_Example() 
{ 
   string imageFileName = Path.Combine(LEAD_VARS.ImagesDir, "MyQRBarcodes.tif"); 
 
   BarcodeEngine engine = new BarcodeEngine(); 
 
   // Create the image to write the barcodes to 
   int resolution = 300; 
   using (RasterImage image = RasterImage.Create((int)(8.5 * resolution), (int)(11.0 * resolution), 1, resolution, RasterColor.FromKnownColor(RasterKnownColor.White))) 
   { 
      // Write two QR barcodes 
      WriteBarcode(engine.Writer, image, QRBarcodeSymbolModel.Model1AutoSize, "QR Data 1", false); 
      WriteBarcode(engine.Writer, image, QRBarcodeSymbolModel.Model2Version30, "QR Data 2", true); 
 
      // Save the image 
      using (RasterCodecs codecs = new RasterCodecs()) 
      { 
         codecs.Save(image, imageFileName, RasterImageFormat.CcittGroup4, 1); 
      } 
   } 
 
   // Now read the barcodes again 
   using (RasterCodecs codecs = new RasterCodecs()) 
   { 
      using (RasterImage image = codecs.Load(imageFileName)) 
      { 
         // Read all the QR barcodes 
         ReadBarcodes(engine.Reader, image); 
      } 
   } 
} 
 
private void WriteBarcode(BarcodeWriter writer, RasterImage image, QRBarcodeSymbolModel symbolModel, string value, bool topLeft) 
{ 
   // Create the barcode data 
   QRBarcodeData barcode = BarcodeData.CreateDefaultBarcodeData(BarcodeSymbology.QR) as QRBarcodeData; 
   barcode.SymbolModel = symbolModel; 
   barcode.Value = value; 
   barcode.Symbology = BarcodeSymbology.QR; 
 
   // We will use the alignment to position the barcodes, so use all of the image 
   barcode.Bounds = new LeadRect(0, 0, image.ImageWidth, image.ImageHeight); 
 
   // Set the write options 
   QRBarcodeWriteOptions options = new QRBarcodeWriteOptions(); 
 
   if (topLeft) 
   { 
      options.HorizontalAlignment = BarcodeAlignment.Near; 
      options.VerticalAlignment = BarcodeAlignment.Near; 
   } 
   else 
   { 
      options.HorizontalAlignment = BarcodeAlignment.Far; 
      options.VerticalAlignment = BarcodeAlignment.Far; 
   } 
 
   options.GroupNumber = 0; 
   options.GroupTotal = 0; 
   options.XModule = 30; 
   options.ECCLevel = QRBarcodeECCLevel.LevelL; 
 
   // Write it 
   Console.WriteLine("Writing barcode with symbol model: {0} and Data: {1}", symbolModel, value); 
   writer.WriteBarcode(image, barcode, options); 
} 
 
private void ReadBarcodes(BarcodeReader reader, RasterImage image) 
{ 
   // Setup read options 
   QRBarcodeReadOptions options = new QRBarcodeReadOptions(); 
   options.EnableDoublePass = false; 
   options.EnableDoublePassIfSuccess = true; 
   options.EnablePreprocessing = true; 
 
   Console.WriteLine("Reading QR barcodes"); 
   BarcodeData[] barcodes = reader.ReadBarcodes(image, LeadRect.Empty, 0, new BarcodeSymbology[] { BarcodeSymbology.QR }, new BarcodeReadOptions[] { options }); 
   Console.WriteLine("{0} barcodes found:", barcodes.Length); 
   foreach (QRBarcodeData barcode in barcodes) 
   { 
      string value = BarcodeData.ParseECIData(barcode.GetData()); 
      if (string.IsNullOrEmpty(value)) 
         value = barcode.Value; 
 
      Console.WriteLine(" At {0}, symbol model: {1} data: {2} and symbology: {3}", barcode.Bounds, barcode.SymbolModel, value, barcode.Symbology); 
   } 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images"; 
}