ByteScout Premium Suite – VB.NET – Barcode image preprocessing filters with barcode reader sdk

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ByteScout Premium Suite – VB.NET – Barcode image preprocessing filters with barcode reader sdk

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ByteScout-Premium-Suite-VB-NET-Barcode-image-preprocessing-filters-with-barcode-reader-sdk.pdf

barcode image preprocessing filters with barcode reader sdk in VB.NET with ByteScout Premium Suite

barcode image preprocessing filters with barcode reader sdk in VB.NET

Easy to understand coding instructions are written to assist you to try-out the features without the requirement to write your own code. ByteScout Premium Suite helps with barcode image preprocessing filters with barcode reader sdk in VB.NET. ByteScout Premium Suite is the bundle that includes twelve SDK products from ByteScout including tools and components for PDF, barcodes, spreadsheets, screen video recording.

The below SDK samples describe how to quickly make your application do barcode image preprocessing filters with barcode reader sdk in VB.NET with the help of ByteScout Premium Suite. If you want to know how it works, then this VB.NET sample code should be copied and pasted into your application’s code editor. Then just compile and run it. These VB.NET sample examples can be used in one or many applications.

ByteScout Premium Suite is available as a free trial. You may get it from our website along with all other source code samples for VB.NET applications.

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Module1.vb

      Imports Bytescout.BarCodeReader

Module Module1
    ''' <summary>
    ''' This exmaple demonstrates the use of image filters to improve the decoding or speed.
    ''' </summary>
    Sub Main()

        Using reader As New Reader("demo", "demo")

            ' Set barcode type to find
            reader.BarcodeTypesToFind.Code128 = True


            ' WORKING WITH LOW CONTRAST BARCODE IMAGES

            ' Add the contrast adjustment for the low contrast image
            reader.ImagePreprocessingFilters.AddContrast(40)

            Console.WriteLine("Image {0}", "low-contrast-barcode.png")

            ' -----------------------------------------------------------------------
            ' NOTE: We can read barcodes from specific page to increase performance .
            ' For sample please refer to "Decoding barcodes from PDF by pages" program.
            ' ----------------------------------------------------------------------- 

            Dim barcodes As FoundBarcode() = reader.ReadFrom("low-contrast-barcode.png")

            If barcodes.Length = 0 Then
                Console.WriteLine("No barcode found!")
            Else
                For Each barcode As FoundBarcode In barcodes
                    Console.WriteLine("Found barcode {0} with value '{1}'", barcode.Type, barcode.Value)
                Next
            End If

            reader.ImagePreprocessingFilters.Clear()
            Console.WriteLine()


            ' WORKING WITH NOISY BARCODE IMAGES

            ' Add the median filter to lower the noise
            reader.ImagePreprocessingFilters.AddMedian()

            Console.WriteLine("Image {0}", "noisy-barcode.png")

            barcodes = reader.ReadFrom("noisy-barcode.png")

            If barcodes.Length = 0 Then
                Console.WriteLine("No barcode found!")
            Else
                For Each barcode As FoundBarcode In barcodes
                    Console.WriteLine("Found barcode {0} with value '{1}'", barcode.Type, barcode.Value)
                Next
            End If

            reader.ImagePreprocessingFilters.Clear()
            Console.WriteLine()


            ' WORKING WITH DENSE AND ILLEGIBLE BARCODES

            ' Add the scale filter to enlarge the barcode to make gaps between bars more distinguishable
            reader.ImagePreprocessingFilters.AddScale(2) ' enlarge twice

            Console.WriteLine("Image {0}", "too-dense-barcode.png")

            barcodes = reader.ReadFrom("too-dense-barcode.png")

            If barcodes.Length = 0 Then
                Console.WriteLine("No barcode found!")
            Else
                For Each barcode As FoundBarcode In barcodes
                    Console.WriteLine("Found barcode {0} with value '{1}'", barcode.Type, barcode.Value)
                Next
            End If

            reader.ImagePreprocessingFilters.Clear()
            Console.WriteLine()


            ' REMOVE EMPTY MARGINS FROM IMAGE TO SPEED UP THE PROCESSING

            ' Add the crop filter to cut off empty margins from the image.
            ' This will not improve the recognition quality but may speed up the processing 
            ' if you enabled multiple barcode types to search. 
            reader.ImagePreprocessingFilters.AddCropDark()

            Console.WriteLine("Image {0}", "barcode-with-large-margins.png")

            barcodes = reader.ReadFrom("barcode-with-large-margins.png")

            If barcodes.Length = 0 Then
                Console.WriteLine("No barcode found!")
            Else
                For Each barcode As FoundBarcode In barcodes
                    Console.WriteLine("Found barcode {0} with value '{1}'", barcode.Type, barcode.Value)
                Next
            End If

            reader.ImagePreprocessingFilters.Clear()
            Console.WriteLine()

        End Using

        Console.WriteLine("Press any key to exit..")
        Console.ReadKey()

    End Sub

End Module