1. IronOCR
2. Troubleshooting
3. Why IronOCR and not Tesseract

Why Choose IronOCR Over Tesseract

Accuracy

Tesseract

• Tesseract is unable to handle images that are rotated, skewed, low DPI, scanned, or have background noise.
• It requires image pre-processing using Photoshop or ImageMagick.
• It can take a long time to process and often provides nonsensical information.

IronOCR

• IronOCR handles pre-processing and applies image filters to simplify the process.
• Users often achieve 99.8% to 100% accuracy with minimal configuration.

Image Compatibility

Tesseract

• Only accepts Leptonica PIX image format, which is an IntPtr C++ object in C#.
• PIX objects are not managed memory. Failure to handle them with care in C# results in memory leaks.

IronOCR

• Images are memory managed.
• Supports a broad range of image formats:
  • MultiFrame TIFF
  • JPEG & JPEG2000
  • GIF
  • PNG
  • System.Drawing Bitmaps, Stream, and Byte Array/Binary image Data (byte[])
• IronSoftware.System.Drawing is anticipated to replace reliance on System.Drawing, allowing a universal Bitmap format.

Performance

Tesseract

• Poorly documented settings that must be fine-tuned to achieve accuracy.
• Dependent on clean documents and pre-processed images.

IronOCR

• Works accurately with zero configuration for most images.
• Utilizes multithreading to fully leverage multi-core processors.
• Even low-resolution images generally yield high accuracy.
• No Photoshop required.

API

Tesseract

• Little to no support and not beginner-friendly:
  1. Requires working with Interop layers. Many found on GitHub are outdated with unresolved issues, memory leaks, and console warnings.
     • May not support .NET Core or Standard.
  2. Working with the command line EXE is difficult to deploy and can be interrupted by virus scanners and security policies.

IronOCR

• A managed and tested .NET Library for Tesseract called IronTesseract.
• Fully documented with IntelliSense support.
• Team of support engineers ready to assist.

Languages

Tesseract

• Supports only 100 languages.

IronOCR

• Supports over 127 built-in languages and allows for custom language pack support.

Conclusion

Tesseract is an excellent resource for C++ developers, but it is not a complete OCR library for .NET. Scanned or photographed images must be pre-processed to be orthogonal, standardized, high-resolution, and free of digital noise before Tesseract can accurately work with them.

In contrast, IronOCR can do this and more, with just a single line of code. IronOCR uses a very finely-tuned Tesseract for its internal OCR engine, built for C#, with a lot of performance improvements and features added as standard.