pdftract/notes/pdftract-3zhf.md

Verification Note: Phase 7.2 Coordinator (pdftract-3zhf)

Work Completed

1. Unified Detection Entry Point

Added TableDetector::detect(&PageContext) -> Vec<GridCandidate> method that:

• Runs line-based detection first (m/l/S, re/S, re/f operators)
• Runs borderless detection second (x0 alignment heuristic)
• Combines results from both pipelines

2. All Child Beads Closed

• ✅ pdftract-88sk (7.2.1): Line-based table detection
• ✅ pdftract-3nwz (7.2.2): Borderless table detection
• ✅ pdftract-2oqh (7.2.3): Span-to-cell assignment
• ✅ pdftract-ilen (7.2.4): Header row detection
• ✅ pdftract-3c4i (7.2.5): Merged cell detection
• ✅ pdftract-5mph (7.2.6): Table JSON output schema integration

3. Critical Tests Pass

PASS: 5x3 Bordered Table

• Test: test_detect_5x3_table
• Location: crates/pdftract-core/src/table/detector.rs:899
• Result: All 15 cells extracted with correct row/column indices

PASS: Merged Header Cell (colspan=3)

• Test: test_detect_merged_cells_colspan_3_critical_test
• Location: crates/pdftract-core/src/table/cell.rs:1707
• Result: Header cell correctly detected with colspan=3

PASS: Borderless Table Detection

• Test: test_detect_borderless_3x3_table_accepted
• Location: crates/pdftract-core/src/table/detector.rs:1040
• Result: Borderless 3-column table detected via x0 alignment

PASS: Two-Page Table Continuation

• Test: test_detect_two_page_tables_basic
• Location: crates/pdftract-core/src/table/output.rs:389
• Result: Table continuation detected and flagged correctly

4. Schema Verification

• File: docs/schema/v1.0/pdftract.schema.json
• Table shape includes all required fields:
  • id, bbox, rows, header_rows
  • detection_method ("line_based" | "borderless")
  • continued, continued_from_prev
  • page_index

5. Documentation

• File: docs/research/table-structure-reconstruction.md
• Contains algorithm diagrams and explanations

Test Results

cargo test --package pdftract-core --lib table
test result: ok. 122 passed; 0 failed; 0 ignored

Files Modified

• crates/pdftract-core/src/table/detector.rs: Added detect() method
• crates/pdftract-core/src/table/mod.rs: Public API exports

Commit

• Hash: e995808
• Message: feat(pdftract-3zhf): add unified TableDetector::detect entry point