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---
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language:
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- ar
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license: mit
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library_name: pytorch
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pipeline_tag: image-to-text
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tags:
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- ocr
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- handwritten-text-recognition
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- arabic
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- khatt
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- crnn
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- ctc
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---
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# ArabicOCR-KHATT — Arabic Handwritten Text Recognition (CRNN-CTC)
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Line-level Arabic handwritten text recognition, trained on the
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[KHATT](https://khatt.ideas2serve.net/) dataset (11,375 handwritten line images).
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The architecture is a CRNN (CNN + BiLSTM) with CTC loss, with **Arabic-specific
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design choices**: input height 96 so diacritic dots stay detectable, 3-zone
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vertical pooling that preserves *where* dots sit (the only difference between
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ba/ta/tha/nun/ya), dot-safe augmentation, and beam-search decoding with an
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Arabic character bigram LM.
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- **Code / training pipeline:** https://github.com/FixFips/ArabicOCR_KHATT
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- **Python package:** `pip install arabicocr-khatt`
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## Usage
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```python
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from arabicocr_khatt import ArabicOCR
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ocr = ArabicOCR.from_pretrained("FixFips/arabicocr-khatt")
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text = ocr.recognize("handwritten_page.jpg") # segments lines automatically
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print(text)
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```
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Or from the command line:
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```bash
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pip install arabicocr-khatt
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arabicocr handwritten_page.jpg
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```
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## Validation metrics (KHATT, best epoch 116)
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| Metric | Value |
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|--------|-------|
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| CER | 6.09% |
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| WER | 27.26% |
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| WER (normalized) | 26.06% |
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| Dot-group CER | 8.24% |
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Dot-group CER measures errors only on dot-differentiated letter groups
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(ba/ta/tha, jim/ha/kha, nun/ya) — the #1 error source in Arabic OCR.
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## Files
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| File | Purpose |
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|------|---------|
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| `crnn_best.pt` | Model checkpoint: `{"model": state_dict, "vocab": list[str], "arch_version": 2}` |
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| `bigram_lm.json` | Arabic character bigram LM for beam-search decoding |
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| `charset_arabic.txt` | 75-class character set (70 characters + 5 special tokens) |
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## Limitations
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- Line-level model: full pages are segmented into lines with classical
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morphology before recognition; complex layouts may segment poorly.
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- Trained only on KHATT handwriting; printed text, historical manuscripts, and
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heavily diacritized text are out of domain.
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- No word-level language model — output is not spell-corrected.
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## Citation
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If you use this model, please also cite the KHATT dataset:
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> Mahmoud, S. A., et al. "KHATT: An open Arabic offline handwritten text database."
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> Pattern Recognition 47.3 (2014): 1096-1112.
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