Leadtools.Barcode Namespace > DatamatrixBarcodeReadOptions Class : EnableDoublePass Property |
[DisplayNameAttribute("Enable double pass")] [DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan")] [DefaultValueAttribute()] [CategoryAttribute(" Options")] public bool EnableDoublePass {get; set;}
'Declaration <DisplayNameAttribute("Enable double pass")> <DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan")> <DefaultValueAttribute()> <CategoryAttribute(" Options")> Public Property EnableDoublePass As Boolean
'Usage Dim instance As DatamatrixBarcodeReadOptions Dim value As Boolean instance.EnableDoublePass = value value = instance.EnableDoublePass
[DisplayNameAttribute("Enable double pass")] [DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan")] [DefaultValueAttribute()] [CategoryAttribute(" Options")] public bool EnableDoublePass {get; set;}
@property (nonatomic, assign) BOOL enableDoublePass;
public boolean getEnableDoublePass() public void setEnableDoublePass(boolean value)
DisplayNameAttribute("Enable double pass") DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan") DefaultValueAttribute() CategoryAttribute(" Options")
get_EnableDoublePass();
set_EnableDoublePass(value);
Object.defineProperty('EnableDoublePass');
[DisplayNameAttribute("Enable double pass")] [DescriptionAttribute("If no barcodes of this symbology is found, auto pre-process the image and then re-scan")] [DefaultValueAttribute()] [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.