Image OCR (Tesseract)

Extract text from images using Tesseract OCR engine with Python wrapper. Cross-platform support for Windows, macOS, and Linux.

Prerequisites

• Tesseract OCR (v5.0+)
• Python packages: pytesseract, Pillow
• Language packs: Chinese (chi_sim) and English (eng) recommended

Install Tesseract

| Platform | Command | |----------|---------| | Windows | Download from UB-Mannheim/tesseract | | macOS | brew install tesseract | | Linux | sudo apt install tesseract-ocr (Debian/Ubuntu) |

Install Python Dependencies

pip install pytesseract Pillow

Usage

Basic OCR

python scripts/ocr.py <image_path> [-l LANGUAGE] [--psm PSM]

Examples:

# Auto-detect Tesseract, use default language (chi_sim+eng)
python scripts/ocr.py screenshot.png

# Specify language
python scripts/ocr.py document.jpg -l chi_sim+eng

# Specify page segmentation mode
python scripts/ocr.py photo.jpg -l eng --psm 6

# Specify Tesseract path manually
python scripts/ocr.py image.png --tesseract-path "C:\Program Files\Tesseract-OCR"

# List installed language packs
python scripts/ocr.py --list-langs

Tesseract Discovery (auto-detection order)

The script finds Tesseract automatically in this order:

1. --tesseract-path CLI argument
2. TESSERACT_PATH environment variable
3. Config file (~/.config/image-ocr/config.json or %APPDATA%/image-ocr/config.json)
4. Common install locations:
   • Windows: C:\Program Files\Tesseract-OCR, C:\Program Files (x86)\Tesseract-OCR
   • macOS: /usr/local/bin/tesseract, /opt/homebrew/bin/tesseract
   • Linux: /usr/bin/tesseract, /usr/local/bin/tesseract
5. System PATH

Persistent Configuration

Create a JSON config file to set a persistent Tesseract path:

Windows: %APPDATA%\image-ocr\config.json macOS/Linux: ~/.config/image-ocr/config.json

{
  "tesseract_path": "/path/to/tesseract"
}

Supported Languages

| Language | Code | Description | |----------|------|-------------| | Chinese Simplified | chi_sim | 简体中文 | | Chinese Traditional | chi_tra | 繁體中文 | | English | eng | English | | Japanese | jpn | 日本語 | | Korean | kor | 한국어 |

Combine multiple languages: chi_sim+eng

Script Location

scripts/ocr.py - Main OCR script

Notes

• For best results, ensure images are clear and well-lit
• Chinese recognition requires chi_sim language pack
• Output is plain text; use --psm flag for specific page segmentation modes
• Verbose diagnostic info (Tesseract version, path, language) is printed to stderr