Leadtools.Barcode Namespace > DatamatrixBarcodeReadOptions Class : EnableDoublePass Property |
[DefaultValueAttribute()] [DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan")] [DisplayNameAttribute("Enable double pass")] [CategoryAttribute(" Options")] public bool EnableDoublePass {get; set;}
'Declaration <DefaultValueAttribute()> <DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan")> <DisplayNameAttribute("Enable double pass")> <CategoryAttribute(" Options")> Public Property EnableDoublePass As Boolean
'Usage Dim instance As DatamatrixBarcodeReadOptions Dim value As Boolean instance.EnableDoublePass = value value = instance.EnableDoublePass
[DefaultValueAttribute()] [DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan")] [DisplayNameAttribute("Enable double pass")] [CategoryAttribute(" Options")] public bool EnableDoublePass {get; set;}
ObjectiveC Syntax
Java Syntax
DefaultValueAttribute() DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan") DisplayNameAttribute("Enable double pass") CategoryAttribute(" Options") get_EnableDoublePass();
set_EnableDoublePass(value);
[DefaultValueAttribute()] [DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan")] [DisplayNameAttribute("Enable double pass")] [CategoryAttribute(" Options")] public: property bool EnableDoublePass { bool get(); void set ( bool 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. This may take extra processing and increase the barcode detection time. Therefore, it is not recommended to always have EnableDoublePass enabled except in certain situations:
The application is reading barcodes of this type exclusively. For example, a dedicated Datamatrix reader. Reading the barcodes always 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 result 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 provide clean images always, for example, a Fax machine or a Scanner. Enabling double pass here ensures that you can read the barcodes regardless of the input's image quality.
The LEADTOOLS .NET C# and VB Barcode demo's leave 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 DatamatrixBarcodeReadOptions.
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