BertCC

BertCC is a context-aware Chinese text converter that uses BERT (Bidirectional Encoder Representations from Transformers) to convert Simplified Chinese (zh_CN) to Traditional Chinese (zh_TW). Unlike dictionary-based approaches, BertCC leverages the power of contextual understanding to provide more accurate conversions.

Features

• Context-Aware Conversion: Utilizes BERT's contextual understanding to make intelligent conversion choices based on surrounding text

  Input:  他向师生发表演说
  BertCC: 他向師生發表演說  ✓
  OpenCC: 他向師生髮表演說  ✗
  

• Configurable Processing:

  • Adjustable batch size for optimal performance on different hardware
  • Configurable overlap between batches to maintain context across segments
  • Optional context prefix to guide conversion

• Unlimited Text Length: Processes text of any length through intelligent batch processing with overlap

• Hardware Flexibility: Supports both CPU and CUDA processing

• Detailed Output Option: Can show conversion probabilities and candidate selections when run in verbose mode

Installation

pip install bertcc

Usage

Command Line Interface

# Basic usage
bertcc "要转换的文字" --batch-size 450 --overlap-size 50

# Using context prefix for proper nouns
bertcc "都是上里作的好事" -c "上里一將是人名。"
# Output: 都是上里作的好事  (preserves "上里" as a name instead of converting to "上裡")

# Show detailed conversion process
bertcc "他的头与发皆白" --verbose

Python API

from bertcc.converter import ConversionConfig, ChineseConverter

config = ConversionConfig(
    batch_size=450,
    overlap_size=50,
    context_prefix='上里一將是人名。',  # Context hint for proper nouns
    device="cuda",  # or "cpu"
    model_name="bert-base-chinese"
)

converter = ChineseConverter(config)
result = converter.convert("都是上里作的好事", show_details=True)

Usage Considerations

Input Text Quality

For optimal conversion results, consider these important guidelines:

1. Pure Chinese Text Preferred:

   Good: 他向师生发表演说
   
   Avoid: <div>他向师生发表演说</div>  // HTML tags may affect context
   

2. Why This Matters:

   • BERT models are trained primarily on natural Chinese text
   • Non-Chinese elements (HTML, markdown, special characters) can:
     • Disrupt the contextual understanding
     • Lead to incorrect character conversions
     • Break the natural language flow

3. Best Practices:

   • Clean input text of HTML/XML tags before conversion
   • Remove or minimize non-Chinese characters where possible
   • Keep formatting markup separate from text being converted
   • Use context prefix for proper nouns rather than special markers

4. Handling Mixed Content: If you must process text with mixed content:

   • Consider splitting the text into Chinese and non-Chinese segments
   • Process Chinese segments separately
   • Reassemble the text after conversion

Configuration Options

Parameter	Description	Default
batch_size	Number of characters processed in each batch	450
overlap_size	Number of overlapping characters between batches	50
context_prefix	Optional prefix to provide additional context	''
device	Computation device ("cuda" or "cpu")	"cuda" if available
model_name	BERT model to use for conversion	"bert-base-chinese"

How It Works

BertCC uses a unique approach to Chinese text conversion:

1. Text Processing:

   • Splits input text into manageable batches with overlap to maintain context
   • Identifies ambiguous characters that have multiple possible Traditional Chinese representations

2. Masking and Prediction:

   • Replaces ambiguous characters with BERT's [MASK] token
   • For example, "发" could be "發" (to express) or "髮" (hair)
   • The surrounding context helps BERT understand which meaning is intended

3. Contextual Decision:

   • BERT model predicts the most likely Traditional Chinese character for each mask
   • Predictions are influenced by:
     • Surrounding text context
     • Optional context prefix (useful for proper nouns)
     • Known character mappings and frequencies

4. Batch Processing:

   • Processes text in overlapping batches to handle long texts
   • Merges results while maintaining consistency at batch boundaries

Limitations

1. Phrase-Level Variations: Cannot handle regional phrase differences between Simplified and Traditional Chinese due to its character-by-character processing architecture. For example:

   CN: 互联网        TW: 網際網路
   CN: 数据库        TW: 資料庫
   CN: 软件          TW: 軟體
   

   BertCC will convert these character-by-character (e.g., 互联网 → 互聯網) rather than using the regionally appropriate phrase (網際網路). This is because the model operates on character-level masking and prediction, not phrase-level transformation. For applications requiring region-specific terminology conversion, additional post-processing or a different approach would be needed.

2. Computational Resources: As a neural network-based solution, BertCC requires more computational resources compared to dictionary-based approaches like OpenCC.

3. Processing Speed: Due to the contextual analysis, conversion speed is slower than dictionary-based methods, though this is mitigated through batch processing.

Comparison with Other Tools

Unlike traditional conversion tools like OpenCC that rely on character-to-character mapping, BertCC:

• Considers the entire context when making conversion decisions
• Handles ambiguous characters more accurately by understanding their usage
• Provides confidence scores for conversions in verbose mode
• Maintains contextual consistency across long texts through overlap processing

Contributing

Contributions are welcome! Please feel free to submit pull requests, report issues, or suggest improvements.

License

Apache License 2.0