| --- |
| language: |
| - ar |
| library_name: kraken |
| pipeline_tag: image-segmentation |
| tags: |
| - arabic |
| - manuscripts |
| - layout-analysis |
| - line-segmentation |
| - kraken |
| license: other |
| --- |
| |
| # Athar Segmentation v4 |
|
|
| `Athar Segmentation v4` is the Kraken/BLLA line-segmentation model deployed |
| with the Athar Arabic manuscript transcription system. It detects line regions |
| and baselines before the separate exp9 recognition model transcribes each crop. |
|
|
| ## ملخص عربي |
|
|
| هذا نموذج القص واكتشاف أسطر المخطوطات العربية المستعمل في منظومة «أثر». |
| النموذج لا يقرأ النص؛ بل يحدد مناطق الأسطر وخطوط الأساس، ثم يمرر القصاصات إلى |
| نموذج التفريغ المستقل. دُرّب على 319 صفحة PAGE-XML من RASAM، وبلغ متوسط |
| `IoU=0.452` في سجل التدريب المحلي. |
|
|
| ## Evidence |
|
|
| | Measurement | Result | |
| |---|---:| |
| | Training pages | 319 RASAM pages | |
| | Recorded mean IoU | 0.452 | |
| | 30-page full-pipeline CER with the older segmenter | 10.06% | |
| | 30-page full-pipeline CER with v4 | 8.43% | |
|
|
| The CER comparison measures the **complete page pipeline**, not segmentation |
| alone. It shows the downstream impact of better crops, while IoU is the direct |
| geometric segmentation metric. Dense or framed layouts can still require human |
| PAGE-XML polygons. |
|
|
| ## Model file |
|
|
| | Field | Value | |
| |---|---| |
| | File | `model.mlmodel` | |
| | Framework | Kraken / BLLA | |
| | SHA-256 | `dc07cdeefe17598535ea3f5b187f7ddd2463baed909138c9ffd274c88b0e9a24` | |
| | Intended input | Full Arabic manuscript page image | |
| | Intended output | Line polygons and baselines | |
|
|
| ## Usage |
|
|
| Install a Kraken version compatible with the model and provide the model to |
| Kraken's segmentation command. The Athar application loads it through: |
|
|
| ```env |
| SEG_MODEL_FILE=model.mlmodel |
| ``` |
|
|
| For scholarly work, inspect and correct the resulting line polygons before |
| accepting a final transcription. Layout segmentation and recognition are |
| separate sources of error. |
|
|
| ## Training data and license note |
|
|
| The recorded training source is RASAM, whose local dataset repository carries |
| an Apache-2.0 license. This repository is initially kept private while the |
| upstream warm-start model provenance and release terms are reviewed. The |
| `license: other` metadata is deliberate; do not infer a permissive weight |
| license until that review is complete. |
|
|
| ## Limitations |
|
|
| - Framed, multi-column, marginal, and heavily overlapping layouts may fail. |
| - The model is specialized for historical Arabic manuscript pages. |
| - IoU does not measure reading order or transcription accuracy. |
| - Human correction of PAGE-XML remains the safest path for complex pages. |
|
|
|
|
