ByteScout Barcode Reader SDK – VB.NET – Two-pass decoding

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ByteScout Barcode Reader SDK – VB.NET – Two-pass decoding

printable version:
ByteScout-BarCode-Reader-SDK-VB-NET-Two-pass-decoding.pdf

two pass decoding in VB.NET and ByteScout BarCode Reader SDK

ByteScout BarCode Reader SDK: the barcode decoder with support for code 39, code 128, QR Code, Datamatrix, GS1, PDF417 and all other popular barcodes. Can read barcodes from images, pdf, tiff documents and live web camera. Supports noisy and damaged documents, can split and merge pdf and tiff documents based on barcodes. Can export barcode decoder results to XML, JSON, CSV and into custom data structures.

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Program.vb

      Imports Bytescout.BarCodeReader

Class Program

    Friend Shared Sub Main(args As String())

        Dim reader As New Reader()
        reader.RegistrationName = "demo"
        reader.RegistrationKey = "demo"

        ' Limit search to 1-dimensional barcodes only (exclude 2D barcodes to speed up the processing).
        ' Change to barcodeReader.BarcodeTypesToFind.SetAll() to scan for all supported 1D and 2D barcode types
        ' or select specific type, e.g. barcodeReader.BarcodeTypesToFind.PDF417 = True
        reader.BarcodeTypesToFind.All1D = True

        ' Input barcode document
        Dim inputDocument As String = "example.pdf"

        Console.WriteLine("First Attempt - Reading barcodes from PDF document...")
        Dim foundBarcodesFirstAttempt As FoundBarcode() = GetBarcodes(reader, inputDocument)

        If Not foundBarcodesFirstAttempt Is Nothing AndAlso foundBarcodesFirstAttempt.Length > 0 Then
            DisplayBarcodeResult(foundBarcodesFirstAttempt)
        Else
            Console.WriteLine("No Barccodes found...")
            ' Try Second attempt
            Console.WriteLine(Environment.NewLine + Environment.NewLine + "Second Attempt - Reading barcodes from PDF document...")

            ' Change PDF rendering resolution
            reader.PDFRenderingResolution = 150

            ' Get found barcodes 
            Dim foundBarcodesSecondAttempt As FoundBarcode() = GetBarcodes(reader, inputDocument)

            If Not foundBarcodesSecondAttempt Is Nothing AndAlso foundBarcodesSecondAttempt.Length > 0 Then
                DisplayBarcodeResult(foundBarcodesSecondAttempt)
            End If
        End If

        ' Cleanup
        reader.Dispose()

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

    End Sub

    ''' <summary>
    ''' Get Barcodes
    ''' </summary>
    Shared Function GetBarcodes(reader As Reader, inputDocument As String) As FoundBarcode()
        ' -----------------------------------------------------------------------
        ' NOTE: We can read barcodes from specific page to increase performance .
        ' For sample please refer to "Decoding barcodes from PDF by pages" program.
        ' ----------------------------------------------------------------------- 
        Return reader.ReadFrom(inputDocument)
    End Function

    ''' <summary>
    ''' Display found barcodes
    ''' </summary>
    Shared Sub DisplayBarcodeResult(foundBarcodes As FoundBarcode())
        For Each barcode As FoundBarcode In foundBarcodes
            Console.WriteLine("Found barcode with type '{0}' and value '{1}' at page {2} at {3}", barcode.Type, barcode.Value, barcode.Page, barcode.Rect.ToString())
        Next
    End Sub

End Class

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60 Day Free Trial or Visit ByteScout BarCode Reader SDK Home Page

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ON-DEMAND REST WEB API

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TwoPassDecoding.NETCore.vbproj

      <?xml version="1.0" encoding="utf-8"?>
<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>netcoreapp2.0</TargetFramework>
    <EnableDefaultCompileItems>false</EnableDefaultCompileItems>
    <GenerateAssemblyCompanyAttribute>false</GenerateAssemblyCompanyAttribute>
    <GenerateAssemblyConfigurationAttribute>false</GenerateAssemblyConfigurationAttribute>
    <GenerateAssemblyFileVersionAttribute>false</GenerateAssemblyFileVersionAttribute>
    <GenerateAssemblyInformationalVersionAttribute>false</GenerateAssemblyInformationalVersionAttribute>
    <GenerateAssemblyProductAttribute>false</GenerateAssemblyProductAttribute>
    <GenerateAssemblyTitleAttribute>false</GenerateAssemblyTitleAttribute>
    <GenerateAssemblyVersionAttribute>false</GenerateAssemblyVersionAttribute>
    <GenerateAssemblyCopyrightAttribute>false</GenerateAssemblyCopyrightAttribute>
    <GenerateAssemblyTrademarkAttribute>false</GenerateAssemblyTrademarkAttribute>
    <GenerateAssemblyCultureAttribute>false</GenerateAssemblyCultureAttribute>
    <GenerateAssemblyDescriptionAttribute>false</GenerateAssemblyDescriptionAttribute>
  </PropertyGroup>
  <ItemGroup>
    <Compile Include="Program.vb" />
    <None Include="example.pdf">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
    </None>
  </ItemGroup>
  <ItemGroup>
    <PackageReference Include="Microsoft.Windows.Compatibility" Version="2.0.0" />
  </ItemGroup>
  <ItemGroup>
    <Reference Include="Bytescout.BarCodeReader">
      <SpecificVersion>False</SpecificVersion>
      <HintPath>c:\Program Files\Bytescout BarCode Reader SDK\netcoreapp2.0\Bytescout.BarCodeReader.dll</HintPath>
    </Reference>
  </ItemGroup>
</Project>

ON-PREMISE OFFLINE SDK

60 Day Free Trial or Visit ByteScout BarCode Reader SDK Home Page

Explore ByteScout BarCode Reader SDK Documentation

Explore Samples

Sign Up for ByteScout BarCode Reader SDK Online Training

ON-DEMAND REST WEB API

Get Your API Key

Explore Web API Docs

Explore Web API Samples

TwoPassDecoding.VS2005.vbproj

      <Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <PropertyGroup>
    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
    <ProductVersion>8.0.50727</ProductVersion>
    <SchemaVersion>2.0</SchemaVersion>
    <ProjectGuid>{5F17DE51-EC94-4A5A-AF58-C4876D4BA652}</ProjectGuid>
    <OutputType>Exe</OutputType>
    <RootNamespace>TwoPassDecoding</RootNamespace>
    <AssemblyName>TwoPassDecoding</AssemblyName>
  </PropertyGroup>
  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
    <DebugSymbols>true</DebugSymbols>
    <DebugType>full</DebugType>
    <Optimize>false</Optimize>
    <OutputPath>bin\Debug\</OutputPath>
    <DefineConstants>DEBUG,TRACE</DefineConstants>
    <ErrorReport>prompt</ErrorReport>
    <WarningLevel>4</WarningLevel>
  </PropertyGroup>
  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
    <DebugType>pdbonly</DebugType>
    <Optimize>true</Optimize>
    <OutputPath>bin\Release\</OutputPath>
    <DefineConstants>TRACE</DefineConstants>
    <ErrorReport>prompt</ErrorReport>
    <WarningLevel>4</WarningLevel>
  </PropertyGroup>
  <Import Project="$(MSBuildBinPath)\Microsoft.VisualBasic.Targets" />
  <ItemGroup>
    <Import Include="Microsoft.VisualBasic" />
    <Import Include="System" />
    <Reference Include="Bytescout.BarCodeReader, Version=8.20.0.1340, Culture=neutral, PublicKeyToken=f7dd1bd9d40a50eb, processorArchitecture=MSIL">
      <SpecificVersion>False</SpecificVersion>
      <HintPath>C:\Program Files\Bytescout BarCode Reader SDK\net2.00\Bytescout.BarCodeReader.dll</HintPath>
    </Reference>
    <Reference Include="System" />
    <Reference Include="System.Data" />
    <Reference Include="System.Drawing" />
    <Reference Include="System.Xml" />
    <Compile Include="Program.vb" />
    <Content Include="example.pdf">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
    </Content>
  </ItemGroup>
</Project>

ON-PREMISE OFFLINE SDK

60 Day Free Trial or Visit ByteScout BarCode Reader SDK Home Page

Explore ByteScout BarCode Reader SDK Documentation

Explore Samples

Sign Up for ByteScout BarCode Reader SDK Online Training

ON-DEMAND REST WEB API

Get Your API Key

Explore Web API Docs

Explore Web API Samples

TwoPassDecoding.VS2008.vbproj

      <Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="3.5">
  <PropertyGroup>
    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
    <ProductVersion>9.0.30729</ProductVersion>
    <SchemaVersion>2.0</SchemaVersion>
    <ProjectGuid>{5F17DE51-EC94-4A5A-AF58-C4876D4BA652}</ProjectGuid>
    <OutputType>Exe</OutputType>
    <RootNamespace>TwoPassDecoding</RootNamespace>
    <AssemblyName>TwoPassDecoding</AssemblyName>
    <OldToolsVersion>2.0</OldToolsVersion>
    <TargetFrameworkVersion>v3.5</TargetFrameworkVersion>
  </PropertyGroup>
  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
    <DebugSymbols>true</DebugSymbols>
    <DebugType>full</DebugType>
    <Optimize>false</Optimize>
    <OutputPath>bin\Debug\</OutputPath>
    <DefineConstants>DEBUG,TRACE</DefineConstants>
    <ErrorReport>prompt</ErrorReport>
    <WarningLevel>4</WarningLevel>
  </PropertyGroup>
  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
    <DebugType>pdbonly</DebugType>
    <Optimize>true</Optimize>
    <OutputPath>bin\Release\</OutputPath>
    <DefineConstants>TRACE</DefineConstants>
    <ErrorReport>prompt</ErrorReport>
    <WarningLevel>4</WarningLevel>
  </PropertyGroup>
  <Import Project="$(MSBuildToolsPath)\Microsoft.VisualBasic.Targets" />
  <ItemGroup>
    <Import Include="Microsoft.VisualBasic" />
    <Import Include="System" />
    <Reference Include="Bytescout.BarCodeReader, Version=8.20.0.1340, Culture=neutral, PublicKeyToken=f7dd1bd9d40a50eb, processorArchitecture=MSIL">
      <SpecificVersion>False</SpecificVersion>
      <HintPath>C:\Program Files\Bytescout BarCode Reader SDK\net3.50\Bytescout.BarCodeReader.dll</HintPath>
    </Reference>
    <Reference Include="System" />
    <Reference Include="System.Data" />
    <Reference Include="System.Drawing" />
    <Reference Include="System.Xml" />
    <Compile Include="Program.vb" />
    <Content Include="example.pdf">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
    </Content>
  </ItemGroup>
</Project>

ON-PREMISE OFFLINE SDK

60 Day Free Trial or Visit ByteScout BarCode Reader SDK Home Page

Explore ByteScout BarCode Reader SDK Documentation

Explore Samples

Sign Up for ByteScout BarCode Reader SDK Online Training

ON-DEMAND REST WEB API

Get Your API Key

Explore Web API Docs

Explore Web API Samples

TwoPassDecoding.VS2010.vbproj

      <?xml version="1.0" encoding="utf-8"?>
<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="4.0">
  <PropertyGroup>
    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
    <ProductVersion>
    </ProductVersion>
    <SchemaVersion>2.0</SchemaVersion>
    <ProjectGuid>{5F17DE51-EC94-4A5A-AF58-C4876D4BA652}</ProjectGuid>
    <OutputType>Exe</OutputType>
    <RootNamespace>TwoPassDecoding</RootNamespace>
    <AssemblyName>TwoPassDecoding</AssemblyName>
    <OldToolsVersion>3.5</OldToolsVersion>
    <TargetFrameworkVersion>v4.0</TargetFrameworkVersion>
  </PropertyGroup>
  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
    <DebugSymbols>true</DebugSymbols>
    <DebugType>full</DebugType>
    <Optimize>false</Optimize>
    <OutputPath>bin\Debug\</OutputPath>
    <DefineConstants>DEBUG,TRACE</DefineConstants>
    <ErrorReport>prompt</ErrorReport>
    <WarningLevel>4</WarningLevel>
  </PropertyGroup>
  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
    <DebugType>pdbonly</DebugType>
    <Optimize>true</Optimize>
    <OutputPath>bin\Release\</OutputPath>
    <DefineConstants>TRACE</DefineConstants>
    <ErrorReport>prompt</ErrorReport>
    <WarningLevel>4</WarningLevel>
  </PropertyGroup>
  <Import Project="$(MSBuildToolsPath)\Microsoft.VisualBasic.Targets" />
  <ItemGroup>
    <Import Include="Microsoft.VisualBasic" />
    <Import Include="System" />
    <Reference Include="Bytescout.BarCodeReader, Version=8.20.0.1340, Culture=neutral, PublicKeyToken=f7dd1bd9d40a50eb, processorArchitecture=MSIL">
      <SpecificVersion>False</SpecificVersion>
      <HintPath>C:\Program Files\Bytescout BarCode Reader SDK\net4.00\Bytescout.BarCodeReader.dll</HintPath>
    </Reference>
    <Reference Include="System" />
    <Reference Include="System.Data" />
    <Reference Include="System.Drawing" />
    <Reference Include="System.Xml" />
    <Compile Include="Program.vb" />
    <Content Include="example.pdf">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
    </Content>
  </ItemGroup>
</Project>