EnableDoublePass Property (MicroPDF417BarcodeReadOptions)

[DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan")]
[DefaultValueAttribute()]
[DisplayNameAttribute("Enable double pass")]
[CategoryAttribute("			Options")]
public bool EnableDoublePass {get; set;}

'Declaration
 
<DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan")>
<DefaultValueAttribute()>
<DisplayNameAttribute("Enable double pass")>
<CategoryAttribute("			Options")>
Public Property EnableDoublePass As Boolean

'Usage
 
Dim instance As MicroPDF417BarcodeReadOptions
Dim value As Boolean
 
instance.EnableDoublePass = value
 
value = instance.EnableDoublePass

[DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan")]
[DefaultValueAttribute()]
[DisplayNameAttribute("Enable double pass")]
[CategoryAttribute("			Options")]
public bool EnableDoublePass {get; set;}

ObjectiveC Syntax

Java Syntax

DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan")
DefaultValueAttribute()
DisplayNameAttribute("Enable double pass")
CategoryAttribute("			Options")
 get_EnableDoublePass();
set_EnableDoublePass(value); 

[DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan")]
[DefaultValueAttribute()]
[DisplayNameAttribute("Enable double pass")]
[CategoryAttribute("			Options")]
public:
property bool EnableDoublePass {
   bool get();
   void set (    bool value);
}

Property Value

When reading 2D barcodes, LEADTOOLS can perform internal auto preprocessing on the image and try again if the engine cannot detect the barcode required. But this may take extra processing which will increase the barcode detection time. Hence, it is not recommended to always have it enabled except in certain situations:

• The application is reading barcodes of this type exclusively. For example, a dedicated MicroPDF417 reader. Here, always reading the barcode is more important than recognition speed.

• The application uses barcode detection on a server. In this case, the time spent on the actual barcode detection is most probably less than the time required to send the image to the server and get the results back due to network latency. Thus, it makes sense to turn this feature on in this situation.

• The images provided may have a small resolution (DPI) or known to come from a source that does not always provide clean images. For example, a Fax machine or a Scanner. Enabling double pass here ensures that you can read the barcodes regardless on the quality of the input image.

• The LEADTOOLS .NET C# and VB Barcode Demo leaves the option disabled by default. When the user tries to read a barcode of this type and the engine cannot find it, it will then ask the user if they want to turn this feature on and try again. An approach like that (or an automated one: read, if fails, enable and read again) can also be used.

For an example, refer to MicroPDF417BarcodeReadOptions.

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

MicroPDF417BarcodeReadOptions Class
MicroPDF417BarcodeReadOptions Members