光學標記識別 (OMR) 是一種自動捕獲和分析標記在特殊類型文檔表單上的數據的過程。這種特殊類型的文件可以由人們在調查表、測試表和其他紙質文件上標記/填寫。在本文中，我們將學習如何使用 C# 開發基于 GUI 的 OMR Sheet Reader 應用程序。我們的解決方案將掃描的 OMR 表圖像作為本地磁盤的輸入，然后識別標記，最后以CSV格式導出標記的注冊號和陰影答案。完成上述步驟后，我們將擁有.NET 中的 C# 光學標記識別 (OMR) 軟件。那么讓我們開始吧。

Aspose.OMR 最新下載

(一) C# 光學標記識別 (OMR) 軟件的特點

我們的光學標記識別 (OMR) 軟件將具有以下功能：

1. 交互式調整識別參數并實時觀察其效果。我們可以調整以下內容：
   • 識別閾值
   • 飛漲
   • 顯示/隱藏氣泡
2. 選擇并加載以下格式的掃描圖像：
   • PNG
   • JPG/JPEG
   • 動圖
   • TIF/TIFF
3. 識別圖像上的光學標記。
4. 以 CSV 格式導出結果并將其保存到本地磁盤。

(二) C# 光學標記識別 .NET API 和 UI 控制

Aspose.OMR for .NET API 允許設計、創建和識別答題卡、測試、MCQ 試卷、測驗、反饋表、調查和選票。此外，它還提供了一個圖形用戶界面控件，可以添加到 .NET UI 應用程序中。我們將在 .NET UI 應用程序中集成 Aspose.OMR for .NET UI 控件，以開發 OMR 掃描儀/閱讀器應用程序。請下載API 的 DLL 或使用NuGet安裝它。

PM> Install-Package Aspose.OMR

(三) 開發 OMR 軟件的步驟

我們可以按照以下步驟開發基于 GUI 的 OMR 掃描儀/閱讀器應用程序：

• 首先，創建一個新項目并選擇WPF App (.NET Framework)項目模板。

• 接下來，在Configure your new project對話框中，輸入Project name，選擇Location并設置其他參數。

• 然后，打開NuGet 包管理器并安裝Aspose.OMR for .NET包。

• 接下來，將新文件DialogHelper.cs添加到項目中。

• 將以下代碼添加到新創建的DialogHelper.cs中。

internal class DialogHelper
{
/// <summary>
/// The filter string for the dialog that opens template images.
/// </summary>
private static readonly string ImageFilesFilterPrompt = "Image files |*.jpg; *.jpeg; *.png; *.gif; *.tif; *.tiff;";

/// <summary>
/// The filter string for the dialog that saves recognition results
/// </summary>
private static readonly string DataExportFilesFilterPrompt = "Comma-Separated Values (*.csv)" + " | *.csv";

/// <summary>
/// Shows Open Image file dialog.
/// </summary>
/// <returns>Path to selected file, or <c>null</c> if no file was selected.</returns>
public static string ShowOpenImageDialog(string suggestedDir = null)
{
OpenFileDialog dialog = new OpenFileDialog();
return ShowDialog(dialog, ImageFilesFilterPrompt, suggestedDir);
}

/// <summary>
/// Shows Save Recognition Results file dialog.
/// </summary>
/// <returns>Path to selected file, or <c>null</c> if no file was selected.</returns>
public static string ShowSaveDataDialog(string suggestedName)
{
SaveFileDialog dialog = new SaveFileDialog();
return ShowDialog(dialog, DataExportFilesFilterPrompt, suggestedName);
}

/// <summary>
/// Displays given dialog and returns its result as a <c>string</c>.
/// </summary>
/// <param name="dialog">The dialog to show.</param>
/// <param name="filter">File type filter string.</param>
/// <param name="suggestedDir">Suggested dialog initial directory</param>
/// <param name="suggestedName">Suggested file name</param>
/// <returns>Path to selected file, or <c>null</c> if no file was selected.</returns>
private static string ShowDialog(FileDialog dialog, string filter, string suggestedDir = null, string suggestedName = null)
{
string fileName = null;

dialog.Filter = filter;
dialog.RestoreDirectory = true;
if (suggestedName != null)
{
dialog.FileName = suggestedName;
}

if (suggestedDir != null)
{
dialog.InitialDirectory = suggestedDir;
}

bool? result = dialog.ShowDialog();
if (result == true)
{
fileName = dialog.FileName;
}

return fileName;
}
}

• 接下來，使用以下 XAML 內容更新MainWindow.xaml文件。

<Window x:Class="OMR_APP.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:OMR_APP"
mc:Ignorable="d"
Title="Aspose OMR Demo" Height="880" Width="1100">
<Grid Background="WhiteSmoke">
<Grid.RowDefinitions>
<RowDefinition Height="40"></RowDefinition>
<RowDefinition Height="*"></RowDefinition>
</Grid.RowDefinitions>

<ToolBar Grid.Row="0" Background="LightGray">
<TextBox Name="txtTemplatePath" Margin="5" Width="400" Height="30" Background="White"
HorizontalContentAlignment="Center" VerticalContentAlignment="Center">
</TextBox>
<Button Margin="5" Width="100" Height="30" Background="White"
Content="Get control" HorizontalContentAlignment="Center" VerticalContentAlignment="Center"
Click="GetButtonClicked"/>
<Separator/>

<Button Margin="5" Width="100" Height="30" Background="White"
Content="Select Image" Click="SelectImageClicked"/>

<Button Margin="5" Width="100" Height="30" Background="White"
Content="Recognize Image" Click="RecognizeImageClicked"/>

<Button Margin="5" Width="100" Height="30" Background="White"
Content="Export Results" Click="ExportResultsClicked"/>
</ToolBar>

<ContentControl Grid.Row="1" x:Name="CustomContentControl"
HorizontalAlignment="Center" VerticalAlignment="Center"/>
</Grid>
</Window>
view rawOMR-Software-CSharp_MainWindow.xaml hosted with ? by GitHub
之后，替換MainWindow.xaml.cs文件中的以下內容。
/// <summary>
/// Template for testing
/// </summary>
private static readonly string TemplateFilePath = @"C:\Files\OMR\Sheet.omr";

/// <summary>
/// Path to the license Aspose.OMR.NET.lic file
/// </summary>
private static readonly string LicensePath = @"";

private CorrectionControl control;

public MainWindow()
{
InitializeComponent();

// Set and show template file path
txtTemplatePath.Text = TemplateFilePath;

// Set license, provide License file Path and uncomment to test full results
//License lic = new License();
//lic.SetLicense(LicensePath);
}

public string UserImagePath { get; set; }

public string DataFolderPath { get; set; }

/// <summary>
/// Loads and displays CorrectionControl
/// </summary>
private void GetButtonClicked(object sender, RoutedEventArgs e)
{
string path = txtTemplatePath.Text;

try
{
OmrEngine engine = new OmrEngine();
TemplateProcessor processor = engine.GetTemplateProcessor(path);

control = engine.GetCorrectionControl(processor);
CustomContentControl.Content = control;
control.Initialize();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message,"Exception");
}
}

/// <summary>
/// Select and display image
/// </summary>
private void SelectImageClicked(object sender, RoutedEventArgs e)
{
if (control == null)
{
return;
}

string imagePath = DialogHelper.ShowOpenImageDialog(this.DataFolderPath);
if (string.IsNullOrEmpty(imagePath))
{
return;
}

this.UserImagePath = imagePath;

control.LoadAndDisplayImage(imagePath);
}

/// <summary>
/// Recognize loaded image
/// </summary>
private void RecognizeImageClicked(object sender, RoutedEventArgs e)
{
if (control == null)
{
return;
}

control.RecognizeImage();
}

/// <summary>
/// Export results to CSV
/// </summary>
private void ExportResultsClicked(object sender, RoutedEventArgs e)
{
if (control == null)
{
return;
}

string imageName = Path.GetFileNameWithoutExtension(this.UserImagePath);

string path = DialogHelper.ShowSaveDataDialog(imageName);
if (string.IsNullOrEmpty(path))
{
return;
}

control.ExportResults(path);

MessageBox.Show("The exported resultant CSV file can be found here : " + path, "Operation Successful");
}

• 最后，運行應用程序。

(四) C# 光學標記識別 (OMR) 軟件演示

以下是我們剛剛創建的 OMR Scanner/Reader 應用程序的演示。

(五) 結論