Single-word bold section headings ('Replace', 'Trash', 'Instructions')
required a paragraph break before AND after, but headings hug their
section's first paragraph — the break-after almost never exists. A
standalone all-bold single word (>=4 chars, paragraph break before or
page top) now classifies; mixed bold lead-ins ('Note: ...') stay
excluded via all_bold.
opendataloader-bench: 0.8567 -> 0.8575, MHS 0.773 -> 0.776; docs 145
+0.118, 069 +0.112 (net of one cover-page layout shuffle at -0.066
where the new output is semantically closer to GT). pdf-evals: 66
snapshots, composite 0.5864 -> 0.5883, sole >0.02 mover positive.
p1244/thermo fixture snapshots regenerated ('Instructions' un-fuses
from its body paragraph — the intended behavior).
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
* fix(headings): digit-only lines do not define heading tiers
A large bold page number (14pt folio over 11pt body) claimed tier 0:
every real heading demoted one level document-wide, and the bold-size
fallback (which requires an empty tier list) was blocked for documents
whose headings match body size.
Bench-neutral (MHS scores relative hierarchy); pdf-evals: 18 docs get
their heading levels back (#### -> ###), semantic composite +0.0006,
no percentile down.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* fix(headings): exclude digit-only lines from the bold fallback tier pass too
The exclusion in the main pass wasn't enough: with the page-number
tier gone, the bold fallback re-collected the same bold folio. Also
regenerates the thermo-freon12 snapshot (cosmetic churn on the
scrambled legend fixture).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
* fix(headings): rescue wrapped bold headings on interleaved column pages
Report pages whose columns can't be detected (6pt gutters) interleave
both columns' lines, which breaks every whitespace signal the bold
heading heuristic relies on: para_threshold inflates to ~3x line
height and a wrapped heading's own internal line gap defeats isolation.
'9.5. Adapting to the New Normal: Changing / Business Models' merged
into the following paragraph.
Four changes:
- merge_wrapped_bold_heading_groups: 2-3 consecutive all-bold
body-size lines merge into one line when the group is isolated
(column-locally, judged by x-overlapping lines only) or starts with
a section number.
- Section-numbered all-bold lines ('9.5. ...') classify as headings
without the standalone/isolation score gate.
- Line unfusing extends to uppercase-start continuations, gated on a
bold-style mismatch between the runs (a bold heading beside regular
body text) — same-style label rows stay joined.
- The unfuse line-side wordiness requirement drops to 2 words so a
wrapped heading's short last line ('Business Models') still splits
from the neighboring column.
opendataloader-bench: overall 0.8554 -> 0.8576, MHS 0.769 -> 0.777;
docs 037 +0.161, 111 +0.157, 039 +0.091, 198 +0.028, none down.
pdf-evals: 63 snapshots, composite 0.5952 -> 0.5964, sole >0.02 mover
positive. thermo-freon12 snapshot regenerated (cosmetic churn on an
already-scrambled 3-column legend).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* fix(headings): review follow-ups — multi-component section numbers, wholly-bold line gate
Single '1. ' prefixes are ordered list items and no longer bypass
isolation; the uppercase unfuse requires the whole line bold (a
heading), not merely its last run, so mixed bold-label/value rows
stay joined.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
* fix(underline): rescue snug-owned underlines from the table-ruling filters
Documents that underline many full-width lines (dense CJK business docs,
legal redlines, 10-K section links) produce span-similar rules at 3+
y-levels — exactly what the repeated-ruling filter treats as table
rulings, so every semantic underline on such pages was discarded. Three
changes fix detection without re-marking real tables:
1. Snug-owner rescue: a rule survives the repeated-ruling filter when
the union of touching text runs on its baseline row owns it (rule
contained within the union's span +0.75em, runs cover >=60% of the
rule, no column-sized gaps between runs). Table row separators fail
ownership: they overshoot their cells' text or match gapped items.
Same-row segmented rules (column-header separators) always stay
discarded, and a rule enclosed by a drawn cell-sized box (rect-grid
tables) is never rescued.
2. Vertical window widened 0.35em -> 0.72em below the baseline: CJK
layouts draw underlines under the full em box, measured at ~0.67em.
3. Prose-table guard in the positions-path suppressor: a detected
'table' whose cells hold flowing prose (>=30% of cells over 100
chars) is a detection artifact of boxed callouts + stacked rules,
not a real table — suppressing there erased every underline on the
page.
Also fixes cluster_x_positions fabricating phantom table columns from
style-split continuation runs (touching items, gap <2pt, now feed one
column start) — the fix that keeps rect-grid table shapes stable while
underlined links inside cells are correctly marked.
Snapshot updates are underline gains on regulation/form fixtures and one
empty spacer-column change in a subscripted header.
Corpus (508-doc public bench sweep): text output byte-identical on all
docs; underlined items +224/-0; strikeout now fires on redline docs.
Item-level GT coverage: is_underline 86->151/405, is_strikeout 0->10/44.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01L3U6BKYCS73DVA83odAfYB
* fix(underline): fraction-bar guard + subscript merge across underline marks
Found by a 202-doc real-world corpus diff (pdf-evals) that exercises the
full markdown pipeline, which the bench-corpus item sweep does not:
1. Math fraction bars and lattice grid lines are underline geometry —
short horizontal rules under digits. Guard: a narrow rule (<=60pt)
with bar-sized text hanging just below it (denominator) never marks.
The below-text width bound matters: tightly-leaded REAL underlines
have a full-width next line below, which must not trip the guard.
2. merge_subscript_items refused to merge when the parent was underlined
but the tiny digit was not (the drawn rule easily misses the digit's
own overlap window) — losing the merge broke subscript tokens inside
table cells (b+2 no longer became b₂). Strikeout boundaries still
block the merge in both directions; only parent-underlined/digit-bare
merges, absorbing with the parent's flags.
Corpus after refinement: underlined items +220/-2 (the 2 are fraction
bars the old code wrongly marked), GT rule-text coverage 149/405
underline + 10/44 strikeout, text output identical on all 508 bench
docs and word-count-identical on the 202 pdf-evals docs.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01L3U6BKYCS73DVA83odAfYB
* fix(underline): address review — grid-evidence veto, strikeout-safe fraction guard, bounded gaps
- Cell-box veto now requires GRID EVIDENCE (a vertically abutting
neighbor rect with x-overlap) instead of a height window: multiline
table cells taller than the old 90pt ceiling veto again, and isolated
filled callout panels (which legitimately contain underlines) no
longer veto at all.
- The fraction guard gates only UNDERLINE marking; rule_strikes_item
still evaluates, so short strikeouts near lower text survive.
- Fraction hug distance tightened to 0.3em so a short last-line at
normal leading is not mistaken for a denominator.
- Continuation-run suppression bounds the negative gap (-4pt): text
overhanging from an adjacent cell keeps its own column start.
Corpus after review fixes: underlined items +222/-2, GT coverage
150/405 underline + 10/44 strikeout, bench text output identical on
all 508 docs, pdf-evals word loss bounded at equation-reflow noise.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01L3U6BKYCS73DVA83odAfYB
* chore: appease clippy (redundant closure)
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01L3U6BKYCS73DVA83odAfYB
---------
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
* fix(markdown): keep isolated headings on sparse pages; gate tagged roles
The isolated-line density guard wiped every isolated line on a page
where they exceeded 25% of lines. On sparse pages (covers, ToC pages
with a lone "CONTENTS" title, section-divider pages) a single heading
is trivially >25%, so the guard erased exactly the line it exists to
find. Require the page to have >=10 lines before the guard runs — the
25% ratio only signals a multi-column misfire on a dense page.
That let more isolated lines through, exposing that the visual heading
heuristic could promote lines already tagged with a non-heading struct
role (list item, blockquote, code, caption, ToC) or set in a monospace
font. Gate the heuristic on those in both converter paths.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* review: extend non-heading role gate; centralize on StructRole method
Move the non-heading-role check to StructRole::is_non_heading_content
and extend it to the content roles the inline allowlist missed: Quote,
Index, Note, Reference, BibEntry, Formula, Form (in addition to the
existing list/quote/caption/toc/code roles).
Figure is deliberately excluded: cover and banner pages routinely tag
the document title inside a Figure next to a seal/logo, and that title
is a real heading — including Figure demoted the LA County protocol
cover title from headings to bold. Verified against the reference.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* review: block table roles from heading promotion too
Add Table/TR/TH/TD/THead/TBody/TFoot to is_non_heading_content. When
table reconstruction falls back and cells reach the line loop as plain
text, a short isolated cell (a TH column header in particular) could be
promoted to a heading. Defensive: no change across either regression
corpus, so pure hardening for the fallback path.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
* fix(markdown): ToC-page suppression, wrapped bold headings, math fragments
Three heading-classification improvements:
- After emitting a "Contents"/"Table of Contents" heading, suppress
heading promotion for the rest of that page: ToC entries are section
titles that look exactly like headings ("1. Overview of OCR Pack")
and whole contents pages came out as stacks of ##.
- merge_heading_lines only merged font-size-tier and struct-tree
headings, so bold-at-body-size headings that wrap emitted two
separate ## lines. Merge a fully-bold line into the previous
fully-bold line when it reads as a wrap continuation (starts
lowercase, tiny Y gap, no terminal punctuation on the previous line).
- Reject display-math fragments from the bold/rarity heading heuristic:
equations ending in an equation number ("S = kB ln W, (2)") and
lead-ins referencing one ("Rearranging Equation (8) gives:"). A bare
trailing colon is deliberately NOT a signal — real headings often end
with colons ("Procedure:").
The p1244 snapshot change is the bold-merge working as intended:
stacked form labels "**Subtotals** **from pages**" now read
"**Subtotals from pages**".
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* review: guard tier path, protect prev headings in merge, narrow (N) rule
All three review findings applied, calibrated against the corpora:
- is_heading_fragment now gates the font-size-tier path too, not just
the rarity heuristic.
- The bold wrap-merge requires the previous line to be tier-less as
suggested; corpus diff confirmed the old behavior was absorbing a
wrapped list-item fragment into a real heading.
- The bare "(N)" suffix rule suppressed real headings ("Nicaea (325)",
appendix numbering). It now requires math evidence: an operator
(=, <=, <<, ...) in the line or ,/: immediately before the number.
Page-of-total running headers ("PM 2 (10)") get an explicit rule
since the old blanket suffix check had been catching them only by
accident.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
* feat(markdown): underline emission, Unicode scripts, style-preserving merges (ENG-5015 2b)
Three formatting losses in the direct-extraction markdown path:
1. text_with_formatting gains <u> run emission (detect_underline option,
default on) using the geometric is_underline flag from 1.9.9.
Underline runs stay free of nested bold/italic markers — consumers
match tag content literally. Heading lines keep plain text for
bold/italic but preserve <u>: the tag carries meaning `#` doesn't.
2. merge_subscript_items now maps absorbed digit scripts to Unicode
sub/superscript forms with direction from the baseline offset
("H"+"2" -> "H₂", "word"+raised "2" -> "word²", "m"+"3" -> "m³").
NFKC/NFKD folds these back to plain digits so text matching
downstream is unaffected; renderers keep the script semantics.
3. merge_text_items no longer merges across bold/italic boundaries —
absorbing a styled run into a plain neighbor erased the styling
before markdown emission ever saw it. On eval docs this recovers
20-82 italic runs per document that previously emitted as plain.
Snapshots regenerated (diffs are the features: CCl₂F₂, m³, underlined
legal section headings, finer bold runs). pdf-evals regression suite:
202/202 real PDFs pass. napi 1.9.9 -> 1.9.10.
Co-authored-by: Cursor <cursoragent@cursor.com>
* fix(extractor): break merges at underline boundaries too (review)
OR-merging underline stretched the eventual <u> span over neighboring
plain fragments. Merge runs now break on any style-flag change, the
redundant accumulator is gone, and format_list_item learned to move
bullet markers outside <u> wrappers so fully-underlined bullet lines
still render as markdown lists. td9264 snapshot regenerated — spans are
tighter (trailing periods correctly outside the tag).
Co-authored-by: Cursor <cursoragent@cursor.com>
* fix(markdown): strip stray spaces before sentence punctuation (review)
Style-boundary item splits can strand a trailing period in its own
fragment, and multiple assembly paths join fragments with spaces,
yielding "word ." artifacts. Rather than chasing every join site, a
postprocess pass removes a space before `.`/`,`/`;` when the mark ends
its token (whitespace, cell boundary `|`, or end of text follows).
Dot leaders/ellipses and mid-token periods are untouched.
Fixes the td9264 "companies ." artifacts and two pre-existing
"armoring ," artifacts in the 2013-app2 snapshot. pdf-evals: zero
markdown diffs across all 203 corpus PDFs vs committed baselines.
Co-authored-by: Cursor <cursoragent@cursor.com>
* fix(tables): trim spaces inside parenthetical cell fragments
* fix(tables): reject sparse prose row-stripe tables
---------
Co-authored-by: Cursor <cursoragent@cursor.com>
* tables: lift detection on shaded-header + alt-row tables (#wired-grids)
Production telemetry on `wired_high_confidence`-classified table regions
showed `detect_vector_grid_in_region_mem` returning a usable grid only
~27% of the time, with the rest falling through to GLM-OCR. Three
surgical fixes target the dominant production shapes:
* Path-fill cell backgrounds: when the page has no `re` rects but draws
cell backgrounds via `m`/`l`/`h`/`f*` sequences, prefer the fill-derived
rects over the few section-level `W*` clip paths that previously won
the priority gate. Activated when fill rects outnumber clip rects ≥3×.
* Dedup-induced cluster splits: page-background rects could pose as
containers in the sub-rect dedup and evict a slightly smaller
table-frame rect, breaking adjacency between column-cell groups so each
column became its own cluster. Origin-anchored containers are now
disqualified from sub-rect dedup. A separate exact-duplicate pass
collapses the cell-padding/text-bg/cell-border triple emissions some
PDFs produce, preserving original order to avoid reshuffling table
output on multi-table pages.
* Prose-words rejection: the `cell-rect` fallback's whole-grid prose
threshold also rejected real tables that include a description column.
Now relaxed when content is well-distributed (≥75% of cols filled),
while keeping the original strictness for prose-in-a-frame layouts.
Two regression fixtures from the opendataloader-bench corpus, covering
the dominant production failure categories:
* `greencomp_competence.pdf` — 2-col shaded-header + plain-body glossary.
Mirrors production crops #1 (Contractions glossary) and #6 (BIO 350
course header).
* `upstage_key_functions.pdf` — 4-col shaded-header + alt-row backgrounds
+ merged left column. Mirrors production crops #2 (Parameter/Value
alt-row), #7 (Spanish XML schema), and #8 (Córdoba multi-row header).
Existing fixtures stay green (doc 51 wrapped-label, doc 128 forecast
six-cols, td9264 snapshot). 133 unit + integration tests pass; clippy
clean.
Bumps napi/package.json 1.8.4 → 1.8.5.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
* tables: tighten prose-in-frame rejection — fixes pdf-evals #30 regression
PR #76's shaded-header detection lift surfaced a regression on
accessory_building_permit_application_1 (TEDS 0.10 → 0.05): a
paragraph of legal text laid out in a 2-column justified block was
being admitted as a 10×2 fake table where every cell holds a
sentence fragment ("I agree to comply...", "I", "It is the property
owner's responsibility..."). Per pdf-evals PR #30 review, this is
the kind of regression production users will notice — the markdown
is structurally and semantically misleading.
Root cause: PR #76's prose-rejection only fires for `num_cols >= 4`,
so the 2-col prose-in-a-frame case slipped past it entirely. The new
fill-priority + dedup changes started producing rects for this layout
that 1.8.4 correctly ignored.
Fix: tighten the prose-in-frame check.
- Lower the column-count guard from `>= 4` to `>= 2`.
- Add a content-length signal as the primary discriminator: when the
prose-words trigger fires AND mean non-empty cell length exceeds
65 chars, reject regardless of column distribution.
The 65-char threshold cleanly separates observed cases:
accessory_building (prose-in-frame): mean 74 chars → REJECT
upstage_key_functions (real 4-col table): mean 53 → admit
greencomp_competence (real 2-col glossary): mean 20 → admit
accessory_building (real 5×3 form data): mean 10 → admit
The well-distributed-cols relaxation that PR #76 added stays —
"label / value / description / benefit" tables (#7, #8 from the
production crops) still pass, but only when their mean cell length
stays below the prose threshold.
New regression test `accessory_building_rejects_prose_in_frame` asserts
both that the real 5×3 form data table survives AND the 10×2 prose
block is rejected. Snapshot test `test_snapshot_td9264` updated to
match new output — old snapshot captured the same prose-in-frame bug
on regulatory text (paragraphs emitted as 3-col `||text||` fake-table
rows). New snapshot emits clean prose paragraphs, which is correct.
Verification:
- cargo test --all: 424 lib + 133 integration + 2 doc tests pass
- cargo fmt --check clean
- cargo clippy -- -D warnings clean (lib-level; pre-existing
test-level clippy issues on the wired-grids branch unaffected)
- Existing fixtures stay green: forecast_table_chart_six_cols (PR
#72), bits_pilani_* (PR #73), greencomp_competence_two_cols and
upstage_key_functions_four_cols (PR #76).
This branch is based on abimaelmartell/wired-grids so it includes
PR #76's commits plus this fix on top. Suggest merging this and
closing #76, OR rebasing #76 to incorporate this fix.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
* tables: drop early-dedup atom — caused broad TOC + matrix corruption
Bisected PR #76's 4 atoms against the SEC 10-K
0001104659-25-093871_183e44ac.pdf which appeared as a TEDS regression
in pdf-evals PR #30. Result:
atom | TOC | perf-graph | qualifications
---------------------------|-----|------------|---------------
fill-priority | ✓ | ✓ | ✓
early-dedup | ✗ | ✗ | ✗
page-bg disqualification | ✓ | ✓ | ✓
prose-relaxation | ✓ | ✓ | ✓
Early-dedup was the SOLE source of all three regressions on this doc.
Tried a more conservative variant (≥3 copies only — pair-duplicates
appear in legit multi-section layouts like 10-K dividers above + below
section headers); didn't fix the regression. The triplet+ duplicates
on this doc are real, intentional rects, not the cell-border + inner-
fill + text-bg pattern PR #76 was targeting.
Drop early-dedup. Mark `greencomp_competence_two_cols` as #[ignore]
since that wired-grid lift only worked WITH early-dedup; a more
surgical lift in `try_build_grid` / `snap_edges` for the
cell-border + inner-fill + text-bg triplet pattern is the right
follow-up. The other PR #76 wins (upstage_key_functions / production
crops #2, #7, #8) still hold; greencomp / production crops #1, #6
revert to GLM until the surgical fix.
Validation on the regression doc:
0001104659 TOC PART II markers: 4 (matches main, was 2 with PR#76)
0001104659 perf-graph data row: 2 (matches main, was 1)
0001104659 qualifications rows: 9 (matches main, was 6)
Validation on the prose-frame doc:
accessory_building fake-table: 0 (matches main, was 1 with PR#76)
accessory_building prose intact: 1 (matches main)
cargo test --all clean, cargo fmt --check clean, cargo clippy --lib
-- -D warnings clean.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The rect-based cell fallback in detect_row_stripe_table_from_cell_rects
derives columns purely from text X-position clustering. When prose
wraps inside a bounding-box rect (chat transcripts, stylized figures),
the word-boundary gaps cluster into many spurious columns, producing
a multi-column "table" that is just fragmented prose.
Count cells containing common English function words (articles,
prepositions, pronouns, common verbs) and reject the fallback when
20%+ of non-empty cells contain any such word. Real tabular data —
labels, units, numbers, short identifiers — rarely contains these.
Update the td9264 snapshot: the government document section that
previously rendered as a malformed table now renders as cleaner
prose + a proper CFR list.
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
* fix: don't reclassify wrapped bold list leads as headings
When a numbered/bulleted list item's bold lead phrase wraps onto a
second visual line, that line is all_bold + standalone, which scored
above the rarity heading threshold and was emitted as #### in the
middle of the item. That reset in_list, so the body continuation
below picked up a stray `- ` bullet via the struct-tree LI path,
shattering a single item into heading + stray bullets.
Guard the font heuristic: when already inside a list, skip heading
classification for lines at the list continuation indent with a Y
gap within para_threshold. Structure-tree headings still win.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
* fix: tighten rect-row span check in propagate_merged_cells
propagate_merged_cells used an overlap-based predicate with ±tol
slop that returned true at shared row boundaries — a rect whose
top exactly equals row N's bottom lies entirely below the row, yet
the predicate considered it to span row N. When multiple background
rects aligned on a shared Y edge (e.g. consecutive row-stripe
shading), each adjacent rect would over-reach by one row, cascading
labels and data from unrelated rows into a single merged cell.
Replace the overlap predicate with a containment check: rect bottom
at or below row bottom, rect top at or above row top (each within
tol). Genuine merged-cell rects fully contain the rows they span;
tangent rects do not.
Update two snapshots that were encoding the old buggy output.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Pre-scan lines to identify "isolated" ones — short lines (1-6 words)
with paragraph breaks both before AND after. These are heading
candidates even at body font size, common in academic papers
("Acknowledgements", "Limitations", "B.3 Prompt Engineering").
Inspired by opendataloader's HeadingProcessor which passes prevNode
and nextNode context to the heading probability scorer.
The isolated signal (+0.3) combines with rarity/bold/standalone
signals. A per-page density guard prevents false positives on
multi-column pages where many lines appear isolated. Continuation
word detection (ending in "the", "and", etc.) filters wrapped
paragraph lines.
MHS=0 docs: 18→13. MHS-S +0.004. No regressions.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Reverts commits 937311c, 1dcb0c6, 0300e96, 999f9a2. The thin-rect-to-line
synthesis and stacked table splitting improved extraction for specific
government PDFs but caused -0.05 TEDS regression on the benchmark by
preempting the heuristic detector with worse line-based grids.
These features need more targeted guards before re-enabling.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Rows with 3+ short-valued cells (avg ≤10 chars) and an empty first cell
are column headers (e.g. "UR | SC | ST | OBC | EWS"), not text overflow
from the previous row. Prevents them from being merged into the
preceding section title row.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Three fixes for better table extraction from spreadsheet-exported PDFs:
1. Convert thin filled rects (< 2pt) to PdfLine objects before line-based
table detection. Many PDFs draw table borders as narrow filled rectangles
instead of stroked paths — these were invisible to the line detector.
2. Relax uniform row spacing rejection (CV 0.05 → 0.02). Spreadsheet
exports have very even row heights that were being rejected as "chart
grids".
3. Fix continuation row merging: don't merge rows where the only non-first
cell content is a long label (section headers like "Category No. 03").
Don't merge first-cell-only rows with long text ("Note: ...").
Also adds multi-Y row splitting in line-based detection and column-aware
table detection skipping for multi-column pages.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Replace ad-hoc bold/ratio heading checks with a unified scoring system
based on font size rarity. For each line, compute:
score = font_rarity * 0.5 + bold * 0.3 + standalone * 0.2
Font rarity measures how infrequently a font size appears across the
document — heading fonts are rare while body text is common. This
approach (from opendataloader's ModeWeightStatistics) naturally adapts
to each document's font distribution instead of relying on fixed
thresholds.
Guards: require font_size >= 0.95 * base_size (no small-font headings),
word_count >= 3, and standalone (paragraph break before).
Benchmark improvement: MHS 0.56→0.58, MHS-S 0.66→0.70, overall +0.003.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Lines with font size 1.10-1.20x body text that are standalone and short
(1-8 words) are promoted to headings. This catches academic paper
headings where the font is only ~10% larger than body text, below the
previous 1.2x threshold.
Also syncs the simpler to_markdown_from_lines path to match the
table-aware path (removes stale colon exclusion).
Benchmark improvement: MHS 0.54→0.56, overall 0.761→0.766.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Caption detection was incorrectly classifying "Table of Contents" as a
caption because it starts with "Table ". Now "Table" and "Figure"
prefixes require a digit, parenthesis, or hash after them — matching
actual captions like "Table 1", "Figure 3.2" but not titles.
Also removes debug logging left from previous iteration.
Benchmark improvement: MHS 0.52→0.54, overall 0.757→0.761.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The colon exclusion was preventing legitimate headings like "Steps for
Using the Microscope:" and "Changing objectives:" from being detected.
The single edge case it was protecting (chart sub-headers) is less
impactful than the many headings it was blocking.
Benchmark improvement: MHS 0.51→0.52, MHS-S 0.61→0.62.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
- Lower minimum item count for body-font table candidates from 9 to 6,
allowing small 2-3 row tables to be detected.
- Allow 2-column body-font tables with short cells (avg ≤25 chars) to
bypass the "table-like content" validation. This catches text-only
definition/category tables (e.g., species lists) without false-positiving
on 2-column paragraph text (which has longer cells).
Benchmark improvement: TEDS 0.498→0.519, overall 0.750→0.754.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Bold lines at body font size that are standalone (preceded by a paragraph
break) and have ≥3 words are promoted to headings. This catches the
common pattern in academic/technical PDFs where section headings use
bold text at the same size as body text.
Guards against false positives: minimum word count, colon-ending
exclusion (labels like "Table I:").
Benchmark improvement: MHS 0.37→0.50, overall 0.71→0.75.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
* feat(tables): improve heuristic detection for borderless wrapped-cell tables
Three changes to the body-font heuristic detector:
1. Adaptive Y-gap in find_table_regions_strict: use median qualifying-row
spacing × 3 instead of fixed 25pt. Tables with wrapped cells have
larger gaps between qualifying rows (those with 3+ X-clusters).
2. Y-only region filtering: use full X range when collecting region items.
The strict X bounds from qualifying rows excluded continuation lines
in wrapped cells, starving find_column_boundaries of items.
3. Merged-band retry: when split_side_by_side splits a page into bands
but no band produces a table, retry heuristic detection on all items
merged as a single band.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
* feat(tables): gap-histogram column detection for small tables + lower avg_cells
Two changes to fix PDF 045 (borderless table with narrow "No." column):
1. Extend gap-histogram column threshold to small tables: when the gap
between within-column jitter and between-column spacing is >10pt
(unambiguous bimodal signal), use the detected threshold even with
fewer than 500 items. Previously only triggered for dense tables.
2. Lower BodyFont avg_cells_per_row minimum from 2.5 to 2.0 to handle
tables with wrapped multi-line cells where continuation lines have
only 1 filled cell.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
* fix(tables): trim empty outer columns + relax partial H-line validation
- Rect detection: trim empty first/last columns instead of rejecting
the whole table. Rect edges often extend beyond text boundaries.
- Line detection: accept tables with 6+ partial horizontal lines
(>15% width) when <3 full-spanning lines exist. Handles tables
with column-level separators instead of full-width rules.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
* feat(tables): cell-rect fallback for tables with variable-width backgrounds
When rect clustering produces a grid that fails validation (empty
interior columns from variable-width cell backgrounds), fall through
to a new strategy: use rect Y-edges for row boundaries and text
X-position clustering for columns. This handles tables like the
opendataloader-bench 088-090 comparison tables where each cell has
its own background rect at different widths.
Also widen failed-cluster hint width cap for large clusters (≥30 rects)
to allow page-spanning table regions.
TEDS score on opendataloader-bench: 0.300 → 0.353.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
* fix(tables): relax vertical line spanning validation for partial borders
Accept tables with 4+ partial vertical lines (>10% table height) when
fewer than 2 span >30%. Handles tables like opendataloader-bench 053
with column-level vertical separators that don't extend the full height.
TEDS: 0.353 → 0.377 on opendataloader-bench.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
* fix(tables): lower cell-rect density threshold + add validation logging
- Lower cell-rect density minimum from 25% to 15% to accept sparser
tables with decorative backgrounds (fixes 147).
- Add debug logging to all heuristic validation paths for diagnosability.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
* feat(tables): relax body-font validations for text-only and 2-column tables
Four fixes closing 71% of the TEDS gap vs opendataloader:
1. Validation 7 (table-like content): bypass numeric content requirement
for tables with 3+ columns that passed all structural checks. Text-only
tables (category lists, program descriptions) are legitimate.
2. Qualifying row threshold: lower from 3+ to 2+ X-clusters per row.
Enables 2-column body-font table detection (fixes 166).
3. Row-stripe max cell length: raise from 500 to 2000 for 3+ column
tables. Tables with paragraph descriptions in one column are valid
(fixes 121).
4. Row-stripe empty-column trimming: apply the same outer-column trim
as grid detection (fixes 121 column-0 rejection).
TEDS: 0.377 → 0.438 on opendataloader-bench (gap: -0.056 vs odl).
TEDS=0 docs: 14 → 9.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
* feat(tables): enable 2-column body-font tables + lower all minimums
- Lower BodyFont minimum columns from 3 to 2 in detect_table_in_region
- Lower BodyFont minimum rows from 3 to 2
- Lower avg_cells_per_row minimum from 2.0 to 1.5 (handles wrapped cells
in 2-column tables)
- Apply empty-outer-column trimming to row-stripe detection (not just grid)
TEDS: 0.438 → 0.468 on opendataloader-bench (gap: -0.027 vs odl).
TEDS=0 docs: 9 → 8. 86% of original gap closed.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
* feat(tables): text-based row fallback + fix 120 flow-chart and 188 leaderboard
Three changes that push TEDS past opendataloader:
1. Cell-rect Y-edge fallback: when rects have too few Y-edges for row
structure, derive rows from text Y-position clustering within the
rect bounding box. Fixes flow-chart tables (120) and column-header-
only rects (188).
2. Lower cell-rect minimum from 20 to 6 rects to catch smaller tables.
3. Relax validation 1 (first-column presence) from 50% to 25% of rows.
Tables with wrapped model names have continuation lines without first
column content.
TEDS: 0.468 → 0.508 on opendataloader-bench.
Now BEATS opendataloader (0.508 vs 0.494, gap=+0.014).
TEDS=0 docs: 8 → 5.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
* feat(tables): wrapped-cell continuation row merging
Merge rows that have fewer filled cells than the header row into the
previous row. Handles wrapped multi-line cells where text overflow
creates extra rows (e.g., "Direct" + "communications" → "Direct
communications").
Conditions: fewer filled cells than header, more than previous row had,
not a data row (numeric), not a short subheader label.
TEDS: 0.508 → 0.522 on opendataloader-bench (now +0.028 vs odl).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
* fix(tables): tighten cell-rect validation + fix continuation-row merging
Cell-rect false positives:
- Raise density threshold back to 25% (from 15%)
- Add max cell length check (500 chars) to reject paragraph content
- Reject disproportionate grids (>20 rows, <4 cols)
Continuation-row merging:
- Wide tables (5+ cols): only merge rows with ≤50% header cells
- Narrow tables (2-4 cols): merge rows with fewer cells than header
- Prevents merging normal data rows in large tables (6_KE_Chart)
while keeping wrapped-cell merging for narrow tables (178)
TEDS: 0.498 on opendataloader-bench (still +0.004 vs odl).
pdf-evals: 191/192 passed, 0 regressions.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Struct-tree tables with incomplete page tagging (e.g., only 22 of 50+
rows tagged on a page) would claim items and block rect detection,
leaving unclaimed items as loose text. Now require struct-tree tables
to capture ≥50% of band items before using them; incomplete trees
fall through to geometry-based detection.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Skip rect-detected tables that overlap with items already claimed by
struct-tree detection. Previously both strategies emitted separate
tables for the same content, doubling the output on tagged PDFs.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
When a PDF has a well-formed structure tree with /Table > /TR > /TD|TH
elements linked to MCIDs, build tables directly from the semantic
hierarchy. Runs as highest-priority detection (step 0) before rect-based,
line-based, and heuristic strategies.
- Add StructTree::extract_tables() to walk the tree and collect table
descriptors with row/cell/MCID info
- Add detect_tables_from_struct_tree() to match MCIDs to TextItems
- Reject tables with <30% MCID cell coverage (stale structure trees)
- Update 2013-app2 snapshot (struct-tree gives valid but different
column ordering)
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
* fix(text): handle Tc/Tw character and word spacing in text width computation
PDFs using Tc (character spacing) and Tw (word spacing) operators for text
justification had words incorrectly split across TextItems. The computed
advance width didn't account for these spacing parameters, causing spurious
spaces mid-word (e.g. "deve lopers" instead of "developers").
- Add Tc/Tw operator handling and graphics state save/restore
- Incorporate char_spacing and word_spacing into compute_string_width_ts
- Add adaptive merge threshold: tighter for lowercase→lowercase junctions,
wider before joining punctuation
- Add unit tests for Tc/Tw width computation and merge behavior
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
* test(fonts): add large Tc width computation test
Verifies that large character spacing values are applied in full
without any artificial cap, matching PDF spec behavior.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
* fix(text): guard against Tc/Tw-inflated widths in merge and join paths
Two targeted fixes to prevent character-spacing (Tc) and word-spacing
(Tw) inflation from causing data quality regressions:
1. should_join_items: reject large negative gaps (< -font_size) that
arise when Tc/Tw inflate item widths past adjacent items. Fixes
FY_2015 merged numbers (e.g. "239.696.0" → "239.69 6.0").
2. merge_text_items: cap effective width for gap computation when Tw
inflates space-containing items beyond 0.85× font_size per char.
Prevents column-level gaps from collapsing into merge range,
recovering table detection for Baldwin-Edwards and similar PDFs.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
* fix(fonts): CID-as-Unicode passthrough and subscript/superscript merging
Add smart CID-as-Unicode passthrough for Identity-H fonts without
ToUnicode maps. Uses /W array median CID heuristic to distinguish
Unicode-CID PDFs (Chromium-generated) from GID-based subsets.
Add merge_subscript_items() pass that merges small-font items (<75%
of dominant font size, ≤4 chars, tightly adjacent) into parent items.
Fixes chemical formulas (NH3, H2O, KClO3), footnote references, and
subscript notation (vf, Hfg, m3/kg) that were previously orphaned
as separate text items.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
* fix(subscripts): restrict merge to purely numeric text only
Tighten subscript merging to only merge items containing ASCII digits
(0-9). This avoids false positives with ordinal indicators (º), letter
subscripts (sol, vf), and small bullet characters (▶) that caused
table restructuring regressions.
Numeric-only keeps the primary wins: chemical formulas (NH3, H2O),
footnote references, and unit notation (m2, m3).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
* fix(subscripts): restrict merge to parent text ending with a letter
Only merge numeric subscripts when the parent item's text ends with
an alphabetic character. Prevents false merges like "33" + "1" in
fractions (33 1/3%), table credit numbers after spaces, and footnote
refs after punctuation (land.1 → land. 1). Chemical formulas (NH3,
H2O, KClO3) still merge correctly since parent ends with a letter.
Reduces pdf-eval regressions from 13 to 2 (both are correct reversions
of over-aggressive footnote merging from the prior commit).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Document titles, column headers, and newsletter mastheads that repeat
on every page were being fully stripped by strip_repeated_lines. Now
the first page's occurrence is preserved so the content appears once.
Fixes missing titles like "VOICE OF SOUTH MARION" in tax certificate
PDFs and column headers in IRS forms.
OCR text layers and some PDF producers emit trailing spaces on each
text item, which combine with gap-based joining to produce double
spaces ("Vice President"). Now collapses runs of 2+ spaces to single
space within lines, preserving leading indentation.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Drop column-width padding from table output. Saves ~37% bytes on
table-heavy PDFs. Markdown renders identically — padding was purely
cosmetic. Optimizes token efficiency for AI agent consumers.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Tables with very wide cells (e.g. 230+ chars from merged schedule columns)
caused massive whitespace padding in every row. Capping alignment at 40
characters reduces output size significantly (franklin: 77KB→24KB,
Closed-Business: 571KB→502KB) without affecting content.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Only skip text with rendering mode 3 (truly invisible). Removes
fill color tracking that was incorrectly hiding white-on-dark text
in presentations and brochures.
Strip leading/trailing digit sequences (page numbers) before frequency
comparison so headers like "Page 5" and "Page 6" are treated as identical.
Group TextLines at the same Y position into Y-bands and propagate removal
to all siblings when any member is stripped. Increase EDGE_LINE_COUNT from
4 to 5 to cover 5-row form column headers (e.g., IRS p1244).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Bumps EDGE_LINE_COUNT from 3 to 4 to strip repeated form column headers
that sit just inside the page margin (4th-from-edge Y position).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add strip_repeated_lines() preprocessing step that removes running
headers and footers before markdown conversion. Uses multiple guard
rails to avoid false positives:
- Edge-line detection: only considers lines among the first/last 3
distinct Y positions on each page (not percentage-based margins)
- Y-position consistency: requires low variance across pages (stddev
< 5% of page span) to distinguish headers from scattered table content
- Position-aware removal: only strips instances at page edges, preserving
body content that happens to match a header/footer text
- Skips structural lines (headings, list items), short lines (<10 chars),
and decorative separators (repeated single characters)
- Frequency threshold: >= max(3, page_count * 30%) distinct pages
New strip_headers_footers option on MarkdownOptions (default: true).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Unit test verifying short sub-header rows (e.g. month names) are not
merged as continuation rows in table formatting. Snapshot test for
2013_app2.pdf pinning the full row-stripe table output.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
When a PDF page has a graph directly above a table (e.g. Figure 2 above
Table II in real-estate-pricing.pdf), the heuristic table detector would
merge graph axis labels and legend items into the table, producing a
corrupted result.
Add rect hint regions: when a small cluster of cell-border rects (4-6)
fails full grid validation (e.g. only row borders, no column dividers),
extract their Y bounding box as a "hint region". The heuristic detector
then runs separately on items inside vs outside hint regions, preventing
unrelated content from being merged into tables.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Rects spanning multiple grid rows (e.g. classification labels) now have
their text consolidated into the first sub-row via propagate_merged_cells().
Also prevent continuation-row merge from folding body data into the header.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add 5 stripped public-domain PDF fixtures and golden markdown snapshots
for CI regression testing. Fix non-deterministic output caused by
HashMap iteration order in font stats, table heuristics, and rect
clustering by adding deterministic tie-breaking.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
