- Integrate Britfone dictionary (MIT, 15k British English IPA entries)
- Add pronunciation parameter: 'british' (default) or 'american'
- British uses Britfone (Received Pronunciation), falls back to CMU
- American uses eng_to_ipa/CMU, falls back to Britfone
- Frontend: dropdown to switch pronunciation, default = British
- API: ?pronunciation=british|american query parameter
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
1. Semantic example matching: instead of attaching example sentences
to the immediately preceding entry, find the vocab entry whose
English word(s) appear in the example. "a broken arm" → matches
"broken" via word overlap, not "egg/Ei". Uses stem matching for
word form variants (break/broken share stem "bro").
2. Cell padding: add 8px padding to each cell region so words at
column/row edges don't get clipped by OCR (fixes "er wollte"
missing at cell boundaries).
3. Treat very short DE text (≤2 chars) as OCR noise, not real
translation — prevents false positives in example detection.
All fixes are generic and deterministic.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add 4 post-processing steps after OCR (no LLM needed):
1. Character confusion fix: I/1/l/| correction using cross-language
context (if DE has "Ich", EN "1" → "I")
2. IPA dictionary replacement: detect [phonetics] brackets, look up
correct IPA from eng_to_ipa (MIT, 134k words) — replaces OCR'd
phonetic symbols with dictionary-correct transcription
3. Comma-split: "break, broke, broken" / "brechen, brach, gebrochen"
→ 3 individual entries when part counts match
4. Example sentence attachment: rows with EN but no DE translation
get attached as examples to the preceding vocab entry
All fixes are deterministic and generic — no hardcoded word lists.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
- Preserve \n between visual lines within cells (instead of joining with space)
- Rejoin hyphenated words split across line breaks (e.g. Fuß-\nboden → Fußboden)
- Split oversized rows (>1.5× median height) into sub-entries when EN/DE
line counts match — deterministic fix for missed Step 4 row boundaries
- Frontend: render \n as <br/>, use textarea for multiline editing
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
- Switch to PP-OCRv5 Latin model (supports ä, ö, ü, ß)
- Use SERVER model for better accuracy
- Lower Det.unclip_ratio 1.6→1.3 to reduce word merging
- Raise Det.box_thresh 0.5→0.6 for stricter detection
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Fix A: Use _group_words_into_lines() with adaptive Y-tolerance to
correctly order words in multi-line cells (fixes word reordering bug).
RapidOCR: Add as alternative OCR engine (PaddleOCR models on ONNX
Runtime, native ARM64). Engine selectable via dropdown in UI or
?engine= query param. Auto mode prefers RapidOCR when available.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
PSM 7 (single line) missed the second line in cells with two lines.
PSM 6 handles multi-line content. Also fix sort order to Y-then-X
for correct reading order.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Backend: build_word_grid() intersects column regions with content rows,
OCRs each cell with language-specific Tesseract, and returns vocabulary
entries with percent-based bounding boxes. New endpoints: POST /words,
GET /image/words-overlay, ground-truth save/retrieve for words.
Frontend: StepWordRecognition with overview + step-through labeling modes,
goToStep callback for row correction feedback loop.
MkDocs: OCR Pipeline documentation added.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Build a word-coverage mask so only pixels near Tesseract word bounding
boxes contribute to the horizontal projection. Image regions (high ink
but no words) are treated as white, preventing illustrations from
merging multiple vocabulary rows into one.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add Step 4 (row detection) between column detection and word recognition.
Uses horizontal projection profiles + whitespace gaps (same method as columns).
Includes header/footer classification via gap-size heuristics.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Column detection now uses vertical projection profiles to find whitespace
gaps between columns, then validates gaps against word bounding boxes to
prevent splitting through words. Old clustering algorithm extracted as
fallback (_detect_columns_by_clustering) for pages with < 2 detected gaps.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
- Reduce left-side threshold from 35% to 20% of content width
- Strong language signal (eng/deu > 0.3) now prevents page_ref assignment
- Increase column_ignore word threshold from 3 to 8 for edge columns
- Apply language guard to Level 1 and Level 2 classification
Fixes: column with deu=0.921 was misclassified as page_ref because
reference score check ran before language analysis.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Address 5 weaknesses found via ground-truth comparison on session df3548d1:
- Add column_ignore for edge columns with < 3 words (margin detection)
- Absorb tiny clusters (< 5% width) into neighbors post-merge
- Restrict page_ref to left 35% of content area across all 3 levels
- Loosen marker thresholds (width < 6%, words <= 15) and add strong
marker score for very narrow non-edge columns (< 4%)
- Add EN/DE position tiebreaker when language signals are both weak
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Sub-alignments within a column (indented words, etc.) were 60-90px apart
and not getting merged at 3%. On a typical 5-col page (~1500px), 6% = ~90px
merges sub-alignments while keeping real column boundaries (~300px) separate.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Clusters now track Y-positions of their words and filter by vertical
coverage (>=30% primary, >=15%+5words secondary) to reject noise from
indentations or page numbers. Merge distance widened to 3% content width.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Ersetzt hardcodierte Positionsregeln durch ein zweistufiges System:
Phase A erkennt Spaltengeometrie (Clustering), Phase B klassifiziert
Typen per Inhalt (Sprache/Rolle) mit 3-stufiger Fallback-Kette.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Replace projection-profile layout analysis with Tesseract word bounding
box clustering to detect 5-column vocabulary layouts (page_ref, EN, DE,
markers, examples). Falls back to projection profiles when < 3 clusters.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
The old displacement-map approach shifted entire rows by a parabolic
profile, creating a circle/barrel distortion. The actual problem is
a linear vertical shear: after deskew aligns horizontal lines, the
vertical column edges are still tilted by ~0.5°.
New approach:
- Detect shear angle from strongest vertical edge slope (not curvature)
- Apply cv2.warpAffine shear to straighten vertical features
- Manual slider: -2.0° to +2.0° in 0.05° steps
- Slider initializes to auto-detected shear angle
- Ground truth question: "Spalten vertikal ausgerichtet?"
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
The old -3.0 to +3.0 scale multiplied the full displacement map (up to ~79px)
directly, causing extreme distortion at values >1. New slider:
- 0% = no correction
- 100% = auto-detected correction (default)
- 200% = double correction
- Step size: 5%
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
- Fix dewarp method selection: prefer methods with >5px curvature over
higher confidence (vertical_edge 79px was being ignored for text_baseline 2px)
- Add grid overlay on left image in Dewarp step for side-by-side comparison
- Add GET /sessions/{id} endpoint to reload session data
- StepDeskew accepts sessionId prop to restore state when navigating back
- SessionInfo type extended with optional deskew_result and dewarp_result
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
