OCR Training Image Generator

A WPF application for generating synthetic OCR training datasets with customizable text effects, distortions, and noise patterns. Built with C# and OpenCV, similar to Python's trdg but with a visual editor and batch processing.

Features

• Visual Settings Editor: Real-time preview, save/load configurations, font selection with previews
• Text Customization: Custom fonts (TTF/OTF), adjustable spacing, alignment, drop shadows, multiple colors
• Image Effects: Blur, perspective warp, skew, rotation, noise, JPG compression artifacts
• Batch Generator: Multi-threaded generation, queue multiple settings files, progress tracking
• String Generator: Create training text with OCR confusion sequences (I1l, O0o, 5Ss, etc.)
• Range/Fixed Values: Most parameters support fixed values or random ranges

Installation

Prerequisites

• .NET 8.0 SDK or later
• Windows OS (WPF application)

Building from Source

git clone https://github.com/yourusername/OcrDatasetGenerator.git
cd OcrDatasetGenerator/OCRTrainingImageGenerator
dotnet build
dotnet run

Dependencies managed via NuGet: OpenCvSharp4, Denxorz.ZoomControl, Newtonsoft.Json

Quick Start

1. Settings Editor: Load fonts and strings → configure appearance → save as XML
2. Batch Generator: Add settings files → set output folder → start generation
3. String Generator (optional): Generate custom training strings with OCR challenges

Output Structure

output_folder/
├── 0.jpg, 1.jpg, 2.jpg, ...
└── labels.txt (format: "filename.jpg text")

Configuration

Settings are saved as XML files with parameters for:

• Text sources (strings file, font folder)
• Appearance (size, spacing, alignment, colors, backgrounds)
• Effects (blur, warp, skew, rotation, noise, compression)
• All numeric values support fixed or random range modes

Example XML:

<OCRGenerationSettings>
  <StringsFilePath>C:\data\strings.txt</StringsFilePath>
  <FontFolderPath>C:\fonts\</FontFolderPath>
  <FontSize UseRange="true">
    <Min>12</Min>
    <Max>48</Max>
  </FontSize>
</OCRGenerationSettings>

Troubleshooting

• Preview not working: Check fonts folder and strings file paths
• Slow generation: Reduce thread count or image dimensions
• Memory issues: Lower thread count or process smaller batches

License

Apache License 2.0 - see LICENSE file

Acknowledgments

Inspired by belval/trdg, built with OpenCvSharp4 and WPF