Merge origin/main into xobjects/text-line-matrix-and-missing-operators

#370 ("bound Form XObject expansion per page") landed on main and rewrote the
same function this branch changes, threading a shared FormWalkBudget through
extract_form_xobject_text_inner.

The production code merged cleanly — main's budget threading and this branch's
text-state handling (line matrix, T*/TL/'/"/Tc/Tw, and fill colour across q/Q)
touch different parts of the operator loop. All six conflicts were in the test
module, where both sides had added a `mod tests` with different helpers; both
suites are kept.

Test-module resolution:
- unified the imports on `use super::*` plus what it does not cover
  (extract_page_text_items, lopdf dictionary/Dictionary/Stream)
- kept main's form_dag / page_invoking_form / extract_form helpers and its six
  budget tests
- kept this branch's doc_with_form_content / form_items / find helpers and its
  eight text-state tests
- form_items now passes the FormWalkBudget that extract_page_text_items gained

14 tests in the module pass; 885 unit tests overall. Extraction of the
motivating document (199AD3d.pdf) is byte-identical to before the merge, at
97.7% word recall.

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "pdf-inspector"
-version = "1.14.0"
+version = "1.14.1"
 edition = "2021"
 autobins = false
 authors = ["Firecrawl Team"]

napi/Cargo.lock

@@ -851,7 +851,7 @@ checksum = "384b8ab6d37215f3c5301a95a4accb5d64aa607f1fcb26a11b5303878451b4fe"
 
 [[package]]
 name = "pdf-inspector"
-version = "1.14.0"
+version = "1.14.1"
 dependencies = [
  "env_logger",
  "include_dir",
@@ -867,7 +867,7 @@ dependencies = [
 
 [[package]]
 name = "pdf-inspector-napi"
-version = "1.14.0"
+version = "1.14.1"
 dependencies = [
  "napi",
  "napi-build",

napi/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "pdf-inspector-napi"
-version = "1.14.0"
+version = "1.14.1"
 edition = "2021"
 
 [lib]

napi/bun.lock

@@ -8,12 +8,12 @@
         "@napi-rs/cli": "^3.4.1",
       },
       "optionalDependencies": {
-        "@firecrawl/pdf-inspector-darwin-arm64": "1.14.0",
-        "@firecrawl/pdf-inspector-linux-arm64-gnu": "1.14.0",
-        "@firecrawl/pdf-inspector-linux-arm64-musl": "1.14.0",
-        "@firecrawl/pdf-inspector-linux-x64-gnu": "1.14.0",
-        "@firecrawl/pdf-inspector-linux-x64-musl": "1.14.0",
-        "@firecrawl/pdf-inspector-win32-x64-msvc": "1.14.0",
+        "@firecrawl/pdf-inspector-darwin-arm64": "1.14.1",
+        "@firecrawl/pdf-inspector-linux-arm64-gnu": "1.14.1",
+        "@firecrawl/pdf-inspector-linux-arm64-musl": "1.14.1",
+        "@firecrawl/pdf-inspector-linux-x64-gnu": "1.14.1",
+        "@firecrawl/pdf-inspector-linux-x64-musl": "1.14.1",
+        "@firecrawl/pdf-inspector-win32-x64-msvc": "1.14.1",
       },
     },
   },

napi/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@firecrawl/pdf-inspector",
-  "version": "1.14.0",
+  "version": "1.14.1",
   "description": "Fast PDF classification and text extraction. Detect text-based vs scanned PDFs, extract text by region with quality checks. Native Rust performance via napi-rs.",
   "main": "index.js",
   "types": "index.d.ts",
@@ -52,11 +52,11 @@
     "@napi-rs/cli": "^3.4.1"
   },
   "optionalDependencies": {
-    "@firecrawl/pdf-inspector-linux-x64-gnu": "1.14.0",
-    "@firecrawl/pdf-inspector-linux-x64-musl": "1.14.0",
-    "@firecrawl/pdf-inspector-linux-arm64-gnu": "1.14.0",
-    "@firecrawl/pdf-inspector-linux-arm64-musl": "1.14.0",
-    "@firecrawl/pdf-inspector-darwin-arm64": "1.14.0",
-    "@firecrawl/pdf-inspector-win32-x64-msvc": "1.14.0"
+    "@firecrawl/pdf-inspector-linux-x64-gnu": "1.14.1",
+    "@firecrawl/pdf-inspector-linux-x64-musl": "1.14.1",
+    "@firecrawl/pdf-inspector-linux-arm64-gnu": "1.14.1",
+    "@firecrawl/pdf-inspector-linux-arm64-musl": "1.14.1",
+    "@firecrawl/pdf-inspector-darwin-arm64": "1.14.1",
+    "@firecrawl/pdf-inspector-win32-x64-msvc": "1.14.1"
   }
 }

pyproject.toml

@@ -6,7 +6,7 @@ build-backend = "maturin"
 name = "pdf-inspector"
 # Keep package versions in sync with `python3 scripts/version.py <version>`.
 # CI publishes automatically when the synchronized change lands on main.
-version = "1.14.0"
+version = "1.14.1"
 description = "Fast PDF inspection, classification, and text extraction with smart scanned vs text-based detection"
 readme = "docs/python.md"
 license = { text = "MIT" }

site/index.html

@@ -975,7 +975,7 @@ result = pdf_inspector.<span class="fn">process_pdf</span>(<span class="str">"do
 <script>
   (() => {
     const MAX_FILE_SIZE = 25 * 1024 * 1024;
-    const WASM_MODULE_URL = "https://cdn.jsdelivr.net/npm/@firecrawl/pdf-inspector-wasm@1.14.0/pdf_inspector_wasm.js";
+    const WASM_MODULE_URL = "https://cdn.jsdelivr.net/npm/@firecrawl/pdf-inspector-wasm@1.14.1/pdf_inspector_wasm.js";
     const input = document.querySelector("#pdf-input");
     const dropZone = document.querySelector("#drop-zone");
     const filePanel = document.querySelector("#demo-file");

src/extractor/content_stream.rs

@@ -19,7 +19,7 @@ use super::fonts::{
     CMapDecisionCache, FontStyleCache,
 };
 use super::underline::UnderlineLine;
-use super::xobjects::{extract_form_xobject_text, get_page_xobjects, XObjectType};
+use super::xobjects::{extract_form_xobject_text, get_page_xobjects, FormWalkBudget, XObjectType};
 use super::{get_number, image_bbox_from_ctm, multiply_matrices};
 
 /// Strip PDF comments (% to end of line) from content stream bytes.
@@ -137,8 +137,11 @@ fn rise_adjusted(tm: &[f32; 6], rise: f32) -> [f32; 6] {
     ]
 }
 
-/// Returns `(page_extraction, has_gid_fonts)` where `has_gid_fonts` indicates
-/// the page uses fonts with unresolvable gid-encoded glyphs.
+/// Returns `(page_extraction, has_gid_fonts, coords_rotated, skipped_invisible)`
+/// where `has_gid_fonts` indicates the page uses fonts with unresolvable
+/// gid-encoded glyphs and `skipped_invisible` reports that invisible (Tr 3)
+/// text was present but suppressed — callers can use it to decide whether an
+/// `include_invisible` retry could recover anything at all.
 pub(crate) fn extract_page_text_items(
     doc: &Document,
     page_id: ObjectId,
@@ -146,7 +149,8 @@ pub(crate) fn extract_page_text_items(
     font_cmaps: &FontCMaps,
     include_invisible: bool,
     style_cache: &mut FontStyleCache,
-) -> Result<(PageExtraction, bool, bool), PdfError> {
+    form_budget: &mut FormWalkBudget,
+) -> Result<(PageExtraction, bool, bool, bool), PdfError> {
     use lopdf::content::Content;
 
     let mut items = Vec::new();
@@ -262,12 +266,15 @@ pub(crate) fn extract_page_text_items(
             content.operations.len(),
             MAX_OPERATIONS
         );
-        return Ok(((Vec::new(), Vec::new(), Vec::new()), false, false));
+        return Ok(((Vec::new(), Vec::new(), Vec::new()), false, false, false));
     }
 
     // Graphics state tracking
     let mut ctm = [1.0f32, 0.0, 0.0, 1.0, 0.0, 0.0]; // Current Transformation Matrix
     let mut text_rendering_mode: i32 = 0; // 0=fill, 1=stroke, 2=fill+stroke, 3=invisible
+                                          // Invisible (Tr 3) text was present but suppressed — reported to callers
+                                          // so an include_invisible retry is attempted only when it can recover.
+    let mut skipped_invisible = false;
     let mut line_width: f32 = 1.0;
     #[derive(Clone)]
     struct SavedGraphicsState {
@@ -494,6 +501,14 @@ pub(crate) fn extract_page_text_items(
                     // For Mixed/template PDFs, include_invisible=true extracts
                     // the OCR text layer that sits behind scanned images.
                     if text_rendering_mode == 3 && !include_invisible {
+                        if op
+                            .operands
+                            .first()
+                            .and_then(get_operand_bytes)
+                            .is_some_and(|raw| !raw.is_empty())
+                        {
+                            skipped_invisible = true;
+                        }
                         if let Some(w_ts) = w_ts_opt {
                             text_matrix[4] += w_ts * text_matrix[0];
                             text_matrix[5] += w_ts * text_matrix[1];
@@ -565,6 +580,16 @@ pub(crate) fn extract_page_text_items(
                 if in_text_block && !op.operands.is_empty() {
                     if let Ok(array) = op.operands[0].as_array() {
                         let font_info = font_widths.get(&current_font);
+                        // Numeric-only TJ arrays (pure kerning) show no
+                        // text — they must not trigger the invisible retry.
+                        if text_rendering_mode == 3
+                            && !include_invisible
+                            && array
+                                .iter()
+                                .any(|el| get_operand_bytes(el).is_some_and(|raw| !raw.is_empty()))
+                        {
+                            skipped_invisible = true;
+                        }
                         let is_invisible = (text_rendering_mode == 3 && !include_invisible)
                             || suppress_glyph_extraction;
                         // Capture first-glyph position for ActualText
@@ -770,6 +795,16 @@ pub(crate) fn extract_page_text_items(
                         )
                     })
                 });
+                if text_rendering_mode == 3
+                    && !include_invisible
+                    && op
+                        .operands
+                        .first()
+                        .and_then(get_operand_bytes)
+                        .is_some_and(|raw| !raw.is_empty())
+                {
+                    skipped_invisible = true;
+                }
                 if !((text_rendering_mode == 3 && !include_invisible)
                     || suppress_glyph_extraction
                     || op.operands.is_empty())
@@ -882,6 +917,7 @@ pub(crate) fn extract_page_text_items(
                                         &ctm,
                                         &mut cmap_decisions,
                                         style_cache,
+                                        form_budget,
                                     );
                                     items.extend(form_items);
                                 }
@@ -1251,6 +1287,12 @@ pub(crate) fn extract_page_text_items(
         }
     }
 
+    if form_budget.was_truncated() {
+        log::warn!(
+            "page {page_num}: Form XObject expansion truncated (invocation or operation budget reached); nested form text may be incomplete"
+        );
+    }
+
     // Underline detection reads only painted ink: `re` rects confirmed by
     // a paint operator plus filled-subpath rects — never clip-only rects,
     // which draw nothing.
@@ -1300,7 +1342,12 @@ pub(crate) fn extract_page_text_items(
 
     let items = super::merge_text_items(items);
     let items = super::merge_subscript_items(items);
-    Ok(((items, rects, lines), has_gid_fonts, coords_rotated))
+    Ok((
+        (items, rects, lines),
+        has_gid_fonts,
+        coords_rotated,
+        skipped_invisible,
+    ))
 }
 
 /// Counts of text operators with horizontal vs rotated combined matrices.
@@ -1498,13 +1545,14 @@ mod tests {
 
         let (doc, page_id) = simple_doc_with_content(content);
         let font_cmaps = FontCMaps::from_doc(&doc);
-        let ((items, _, _), _, _) = extract_page_text_items(
+        let ((items, _, _), _, _, _) = extract_page_text_items(
             &doc,
             page_id,
             1,
             &font_cmaps,
             false,
             &mut FontStyleCache::new(),
+            &mut FormWalkBudget::new(),
         )
         .unwrap();
         items
@@ -1734,9 +1782,10 @@ BT /F1 12 Tf 0 1 -1 0 240 100 Tm (WORLD) Tj ET
             &font_cmaps,
             false,
             &mut FontStyleCache::new(),
+            &mut FormWalkBudget::new(),
         )
         .unwrap();
-        let ((items, rects, lines), _has_gid, _coords_rotated) = result;
+        let ((items, rects, lines), _has_gid, _coords_rotated, _skipped_invisible) = result;
         assert!(items.is_empty());
         assert!(rects.is_empty());
         assert!(lines.is_empty());
@@ -1817,13 +1866,14 @@ BT 30 700 Tm <41> Tj ET";
         doc.trailer.set("Root", Object::Reference(catalog_id));
 
         let font_cmaps = FontCMaps::from_doc(&doc);
-        let ((items, _, _), _, _) = extract_page_text_items(
+        let ((items, _, _), _, _, _) = extract_page_text_items(
             &doc,
             page_id,
             1,
             &font_cmaps,
             false,
             &mut FontStyleCache::new(),
+            &mut FormWalkBudget::new(),
         )
         .unwrap();
         let text = items

src/extractor/mod.rs

@@ -37,6 +37,7 @@ pub(crate) use layout::group_prefiltered_items_into_lines_with_thresholds_and_re
 pub(crate) use layout::is_newspaper_layout;
 pub(crate) use layout::ColumnRegion;
 pub use layout::{group_into_lines, group_into_lines_preserving_all_text};
+pub(crate) use xobjects::FormWalkBudget;
 
 // ---------------------------------------------------------------------------
 // Public API
@@ -282,18 +283,22 @@ fn extract_positioned_text_impl(
             font_cmaps,
             include_invisible,
             &mut style_cache,
+            &mut FormWalkBudget::new(),
         );
-        let ((mut items, mut rects, mut lines), has_gid_fonts, coords_rotated) = match page_result {
-            Ok(extraction) => extraction,
-            Err(error) if required_pages.is_some_and(|required| !required.contains(page_num)) => {
-                debug!(
-                    "page {}: skipping context-only extraction error: {}",
-                    page_num, error
-                );
-                continue;
-            }
-            Err(error) => return Err(error),
-        };
+        let ((mut items, mut rects, mut lines), has_gid_fonts, coords_rotated, _skipped_invisible) =
+            match page_result {
+                Ok(extraction) => extraction,
+                Err(error)
+                    if required_pages.is_some_and(|required| !required.contains(page_num)) =>
+                {
+                    debug!(
+                        "page {}: skipping context-only extraction error: {}",
+                        page_num, error
+                    );
+                    continue;
+                }
+                Err(error) => return Err(error),
+            };
         // Clip to the visible page box: single-page extracts and imposed
         // spreads keep neighboring pages' content in the stream, positioned
         // outside the CropBox. Extracting it interleaves invisible text into

src/extractor/xobjects.rs

@@ -16,6 +16,76 @@ use super::{get_number, image_bbox_from_ctm, multiply_matrices};
 
 const MAX_FORM_XOBJECT_DEPTH: u8 = 5;
 
+/// Upper bound on Form XObject invocations during a single page extraction.
+/// Depth alone is not enough: an acyclic DAG where each form invokes the next
+/// N times expands to N^depth work before the depth cap is reached.
+const MAX_FORM_XOBJECT_INVOCATIONS: usize = 10_000;
+
+/// Upper bound on content-stream operations walked across all Form XObject
+/// expansions for a page. Nested forms are decoded independently of the
+/// page-level operation cap, so this keeps total form work in the same
+/// ballpark as that page cap.
+const MAX_FORM_XOBJECT_OPERATIONS: usize = 1_000_000;
+
+/// Shared budget for Form XObject expansion on a page. Bounds both nested DAG
+/// expansion and repeated sibling `/Do` invocations of the same form.
+pub(crate) struct FormWalkBudget {
+    invocations: usize,
+    operations: usize,
+    max_invocations: usize,
+    max_operations: usize,
+    truncated: bool,
+}
+
+impl FormWalkBudget {
+    pub(crate) fn new() -> Self {
+        Self::with_limits(MAX_FORM_XOBJECT_INVOCATIONS, MAX_FORM_XOBJECT_OPERATIONS)
+    }
+
+    fn with_limits(max_invocations: usize, max_operations: usize) -> Self {
+        Self {
+            invocations: 0,
+            operations: 0,
+            max_invocations,
+            max_operations,
+            truncated: false,
+        }
+    }
+
+    fn exhausted(&mut self) -> bool {
+        if self.invocations >= self.max_invocations || self.operations >= self.max_operations {
+            self.truncated = true;
+            true
+        } else {
+            false
+        }
+    }
+
+    fn charge_invocation(&mut self) -> bool {
+        if self.exhausted() {
+            return false;
+        }
+        self.invocations += 1;
+        true
+    }
+
+    /// Charge one walked content-stream operator. Independent of the
+    /// invocation cap so a form that was already admitted can finish its
+    /// stream (up to the operation cap).
+    fn charge_operation(&mut self) -> bool {
+        if self.operations >= self.max_operations {
+            self.truncated = true;
+            return false;
+        }
+        self.operations += 1;
+        true
+    }
+
+    pub(crate) fn was_truncated(&self) -> bool {
+        self.truncated
+    }
+}
+
 pub(crate) enum XObjectType {
     Image,
     Form(ObjectId),
@@ -109,6 +179,7 @@ fn collect_xobjects_from_dict(
 }
 
 /// Extract text items from a Form XObject
+#[allow(clippy::too_many_arguments)]
 pub(crate) fn extract_form_xobject_text(
     doc: &Document,
     form_id: ObjectId,
@@ -117,6 +188,7 @@ pub(crate) fn extract_form_xobject_text(
     parent_ctm: &[f32; 6],
     cmap_decisions: &mut CMapDecisionCache,
     style_cache: &mut FontStyleCache,
+    budget: &mut FormWalkBudget,
 ) -> Vec<TextItem> {
     extract_form_xobject_text_inner(
         doc,
@@ -127,6 +199,7 @@ pub(crate) fn extract_form_xobject_text(
         cmap_decisions,
         style_cache,
         0,
+        budget,
     )
 }
 
@@ -140,11 +213,16 @@ fn extract_form_xobject_text_inner(
     cmap_decisions: &mut CMapDecisionCache,
     style_cache: &mut FontStyleCache,
     depth: u8,
+    budget: &mut FormWalkBudget,
 ) -> Vec<TextItem> {
     use lopdf::content::Content;
 
     let mut items = Vec::new();
 
+    if !budget.charge_invocation() {
+        return items;
+    }
+
     // Get the Form XObject stream
     let Ok(Object::Stream(stream)) = doc.get_object(form_id) else {
         return items;
@@ -246,19 +324,55 @@ fn extract_form_xobject_text_inner(
     let mut current_font = String::new();
     let mut current_font_size: f32 = 12.0;
     let mut text_matrix = [1.0f32, 0.0, 0.0, 1.0, 0.0, 0.0];
+    // Text line matrix (TLM) — Td/TD/T* move relative to the start of the
+    // current line, not to the position left by the last show operator.
+    let mut line_matrix = [1.0f32, 0.0, 0.0, 1.0, 0.0, 0.0];
+    let mut text_leading: f32 = 0.0; // TL parameter (text-space units)
+    let mut char_spacing: f32 = 0.0; // Tc parameter
+    let mut word_spacing: f32 = 0.0; // Tw parameter
     let mut in_text_block = false;
     let mut fill_is_white = false;
     let mut ctm = base_ctm;
-    let mut ctm_stack: Vec<[f32; 6]> = Vec::new();
+
+    // Text state (Tc/Tw/TL/Tf) and the fill colour are part of the graphics
+    // state and must be saved/restored by q/Q alongside the CTM.
+    #[derive(Clone)]
+    struct GraphicsState {
+        ctm: [f32; 6],
+        char_spacing: f32,
+        word_spacing: f32,
+        text_leading: f32,
+        current_font: String,
+        current_font_size: f32,
+        fill_is_white: bool,
+    }
+    let mut ctm_stack: Vec<GraphicsState> = Vec::new();
 
     for op in &content.operations {
+        if !budget.charge_operation() {
+            break;
+        }
         match op.operator.as_str() {
             "q" => {
-                ctm_stack.push(ctm);
+                ctm_stack.push(GraphicsState {
+                    ctm,
+                    char_spacing,
+                    word_spacing,
+                    text_leading,
+                    current_font: current_font.clone(),
+                    current_font_size,
+                    fill_is_white,
+                });
             }
             "Q" => {
                 if let Some(saved) = ctm_stack.pop() {
-                    ctm = saved;
+                    ctm = saved.ctm;
+                    char_spacing = saved.char_spacing;
+                    word_spacing = saved.word_spacing;
+                    text_leading = saved.text_leading;
+                    current_font = saved.current_font;
+                    current_font_size = saved.current_font_size;
+                    fill_is_white = saved.fill_is_white;
                 }
             }
             "cm" => {
@@ -276,7 +390,7 @@ fn extract_form_xobject_text_inner(
                         let xobj_name = String::from_utf8_lossy(name).to_string();
                         match form_xobjects.get(&xobj_name) {
                             Some(XObjectType::Form(nested_id)) => {
-                                if depth < MAX_FORM_XOBJECT_DEPTH {
+                                if depth < MAX_FORM_XOBJECT_DEPTH && !budget.exhausted() {
                                     let nested_items = extract_form_xobject_text_inner(
                                         doc,
                                         *nested_id,
@@ -286,6 +400,7 @@ fn extract_form_xobject_text_inner(
                                         cmap_decisions,
                                         style_cache,
                                         depth + 1,
+                                        budget,
                                     );
                                     items.extend(nested_items);
                                 }
@@ -321,6 +436,7 @@ fn extract_form_xobject_text_inner(
             "BT" => {
                 in_text_block = true;
                 text_matrix = [1.0, 0.0, 0.0, 1.0, 0.0, 0.0];
+                line_matrix = text_matrix;
             }
             "ET" => {
                 in_text_block = false;
@@ -333,12 +449,33 @@ fn extract_form_xobject_text_inner(
                     current_font_size = get_number(&op.operands[1]).unwrap_or(12.0);
                 }
             }
+            "TL" => {
+                // Set text leading (used by T*, ', and ")
+                if let Some(tl) = op.operands.first().and_then(get_number) {
+                    text_leading = tl;
+                }
+            }
+            "Tc" => {
+                if let Some(tc) = op.operands.first().and_then(get_number) {
+                    char_spacing = tc;
+                }
+            }
+            "Tw" => {
+                if let Some(tw) = op.operands.first().and_then(get_number) {
+                    word_spacing = tw;
+                }
+            }
             "Td" | "TD" => {
+                // Move text position: TLM = T(tx,ty) x TLM; Tm = TLM
                 if op.operands.len() >= 2 {
                     let tx = get_number(&op.operands[0]).unwrap_or(0.0);
                     let ty = get_number(&op.operands[1]).unwrap_or(0.0);
-                    text_matrix[4] += tx * text_matrix[0] + ty * text_matrix[2];
-                    text_matrix[5] += tx * text_matrix[1] + ty * text_matrix[3];
+                    line_matrix[4] += tx * line_matrix[0] + ty * line_matrix[2];
+                    line_matrix[5] += tx * line_matrix[1] + ty * line_matrix[3];
+                    text_matrix = line_matrix;
+                    if op.operator == "TD" {
+                        text_leading = -ty;
+                    }
                 }
             }
             "Tm" => {
@@ -347,8 +484,20 @@ fn extract_form_xobject_text_inner(
                         text_matrix[i] =
                             get_number(operand).unwrap_or(if i == 0 || i == 3 { 1.0 } else { 0.0 });
                     }
+                    line_matrix = text_matrix;
                 }
             }
+            "T*" => {
+                // Move to start of next line: equivalent to `0 -TL Td`
+                let tl = if text_leading != 0.0 {
+                    text_leading
+                } else {
+                    current_font_size * 1.2
+                };
+                line_matrix[4] += (-tl) * line_matrix[2];
+                line_matrix[5] += (-tl) * line_matrix[3];
+                text_matrix = line_matrix;
+            }
             "g" => {
                 if let Some(gray) = op.operands.first().and_then(get_number) {
                     fill_is_white = gray > 0.95;
@@ -384,17 +533,33 @@ fn extract_form_xobject_text_inner(
                     _ => fill_is_white = false,
                 }
             }
-            "Tj" => {
-                if in_text_block && !op.operands.is_empty() {
+            "Tj" | "'" | "\"" => {
+                // `'` = move to next line then show; `"` = set word/char spacing,
+                // move to next line, then show (string is the last operand).
+                if op.operator != "Tj" {
+                    if op.operator == "\"" && op.operands.len() >= 3 {
+                        word_spacing = get_number(&op.operands[0]).unwrap_or(word_spacing);
+                        char_spacing = get_number(&op.operands[1]).unwrap_or(char_spacing);
+                    }
+                    let tl = if text_leading != 0.0 {
+                        text_leading
+                    } else {
+                        current_font_size * 1.2
+                    };
+                    line_matrix[4] += (-tl) * line_matrix[2];
+                    line_matrix[5] += (-tl) * line_matrix[3];
+                    text_matrix = line_matrix;
+                }
+                if let (true, Some(show_operand)) = (in_text_block, op.operands.last()) {
                     if fill_is_white {
                         if let Some(font_info) = font_widths.get(&current_font) {
-                            if let Some(raw_bytes) = get_operand_bytes(&op.operands[0]) {
+                            if let Some(raw_bytes) = get_operand_bytes(show_operand) {
                                 let w_ts = compute_string_width_ts(
                                     raw_bytes,
                                     font_info,
                                     current_font_size,
-                                    0.0,
-                                    0.0,
+                                    char_spacing,
+                                    word_spacing,
                                 );
                                 text_matrix[4] += w_ts * text_matrix[0];
                                 text_matrix[5] += w_ts * text_matrix[1];
@@ -403,7 +568,7 @@ fn extract_form_xobject_text_inner(
                         continue;
                     }
                     if let Some(text) = extract_text_from_operand(
-                        &op.operands[0],
+                        show_operand,
                         &current_font,
                         font_base_names.get(&current_font).map(|s| s.as_str()),
                         font_cmaps,
@@ -419,13 +584,13 @@ fn extract_form_xobject_text_inner(
                             * type3_scales.get(&current_font).copied().unwrap_or(1.0);
                         let (x, y) = (combined[4], combined[5]);
                         let width = if let Some(font_info) = font_widths.get(&current_font) {
-                            if let Some(raw_bytes) = get_operand_bytes(&op.operands[0]) {
+                            if let Some(raw_bytes) = get_operand_bytes(show_operand) {
                                 let w_ts = compute_string_width_ts(
                                     raw_bytes,
                                     font_info,
                                     current_font_size,
-                                    0.0,
-                                    0.0,
+                                    char_spacing,
+                                    word_spacing,
                                 );
                                 text_matrix[4] += w_ts * text_matrix[0];
                                 text_matrix[5] += w_ts * text_matrix[1];
@@ -548,8 +713,8 @@ fn extract_form_xobject_text_inner(
                                         raw_bytes,
                                         fi,
                                         current_font_size,
-                                        0.0,
-                                        0.0,
+                                        char_spacing,
+                                        word_spacing,
                                     );
                                 }
                             }
@@ -683,3 +848,415 @@ pub(crate) fn get_form_fonts<'a>(
 
     fonts
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::extractor::content_stream::extract_page_text_items;
+    use lopdf::{dictionary, Dictionary, Stream};
+
+    /// Build an acyclic Form XObject DAG: `levels` form objects, each non-leaf
+    /// invoking the next form `branches` times. The leaf draws a single `(X)`.
+    /// Returns `(doc, root_form_id)`.
+    fn form_dag(branches: usize, levels: usize) -> (Document, ObjectId) {
+        assert!(levels >= 2);
+        let mut doc = Document::new();
+        let font_id = doc.add_object(dictionary! {
+            "Type" => "Font",
+            "Subtype" => "Type1",
+            "BaseFont" => "Helvetica",
+        });
+        let ids: Vec<ObjectId> = (0..levels).map(|_| doc.new_object_id()).collect();
+        for level in 0..levels {
+            let stream = if level + 1 == levels {
+                Stream::new(
+                    dictionary! {
+                        "Type" => "XObject",
+                        "Subtype" => "Form",
+                        "BBox" => vec![0.into(), 0.into(), 100.into(), 100.into()],
+                        "Resources" => dictionary! {
+                            "Font" => dictionary! {
+                                "F1" => Object::Reference(font_id),
+                            },
+                        },
+                    },
+                    b"BT /F1 10 Tf 10 10 Td (X) Tj ET\n".to_vec(),
+                )
+            } else {
+                let next_name = format!("Fm{}", level + 1);
+                let content = format!("/{next_name} Do\n").repeat(branches);
+                let mut xobjects = Dictionary::new();
+                xobjects.set(next_name, Object::Reference(ids[level + 1]));
+                let mut resources = Dictionary::new();
+                resources.set("XObject", Object::Dictionary(xobjects));
+                let mut dict = dictionary! {
+                    "Type" => "XObject",
+                    "Subtype" => "Form",
+                    "BBox" => vec![0.into(), 0.into(), 100.into(), 100.into()],
+                };
+                dict.set("Resources", Object::Dictionary(resources));
+                Stream::new(dict, content.into_bytes())
+            };
+            doc.set_object(ids[level], Object::Stream(stream));
+        }
+        (doc, ids[0])
+    }
+
+    fn page_invoking_form(mut doc: Document, form_id: ObjectId) -> (Document, ObjectId) {
+        let content_id = doc.add_object(Object::Stream(Stream::new(
+            dictionary! {},
+            b"/Fm0 Do\n".to_vec(),
+        )));
+        let page_id = doc.add_object(dictionary! {
+            "Type" => "Page",
+            "Contents" => Object::Reference(content_id),
+            "Resources" => dictionary! {
+                "XObject" => dictionary! {
+                    "Fm0" => Object::Reference(form_id),
+                },
+            },
+            "MediaBox" => vec![0.into(), 0.into(), 612.into(), 792.into()],
+        });
+        let pages_id = doc.add_object(dictionary! {
+            "Type" => "Pages",
+            "Count" => Object::Integer(1),
+            "Kids" => vec![Object::Reference(page_id)],
+        });
+        let catalog_id = doc.add_object(dictionary! {
+            "Type" => "Catalog",
+            "Pages" => Object::Reference(pages_id),
+        });
+        doc.trailer.set("Root", Object::Reference(catalog_id));
+        (doc, page_id)
+    }
+
+    fn extract_form(
+        doc: &Document,
+        form_id: ObjectId,
+        budget: &mut FormWalkBudget,
+    ) -> Vec<TextItem> {
+        extract_form_xobject_text(
+            doc,
+            form_id,
+            1,
+            &FontCMaps::from_doc(doc),
+            &[1.0, 0.0, 0.0, 1.0, 0.0, 0.0],
+            &mut CMapDecisionCache::new(),
+            &mut FontStyleCache::new(),
+            budget,
+        )
+    }
+
+    #[test]
+    fn nested_form_still_extracts_leaf_text() {
+        let (doc, root) = form_dag(1, 3);
+        let items = extract_form(&doc, root, &mut FormWalkBudget::new());
+        assert_eq!(items.len(), 1);
+        assert_eq!(items[0].text, "X");
+    }
+
+    #[test]
+    fn acyclic_form_dag_within_budget_keeps_all_leaves() {
+        // 4 sibling invocations across 4 nested levels → 4^4 leaf drawings.
+        // Default budgets are far above 256, so legitimate nesting is intact.
+        let (doc, root) = form_dag(4, 5);
+        let items = extract_form(&doc, root, &mut FormWalkBudget::new());
+        assert_eq!(items.len(), 4usize.pow(4));
+        assert!(items.iter().all(|item| item.text == "X"));
+    }
+
+    #[test]
+    fn acyclic_form_dag_stops_at_invocation_budget() {
+        // Same DAG as above would draw 256 leaves; a tiny invocation cap must
+        // stop expansion rather than walking the full tree.
+        let (doc, root) = form_dag(4, 5);
+        let mut budget = FormWalkBudget::with_limits(20, MAX_FORM_XOBJECT_OPERATIONS);
+        let items = extract_form(&doc, root, &mut budget);
+        assert!(
+            items.len() < 4usize.pow(4),
+            "invocation budget must truncate DAG expansion; got {} items",
+            items.len()
+        );
+        assert!(budget.was_truncated());
+    }
+
+    #[test]
+    fn form_operations_stop_at_budget() {
+        let mut doc = Document::new();
+        let font_id = doc.add_object(dictionary! {
+            "Type" => "Font",
+            "Subtype" => "Type1",
+            "BaseFont" => "Helvetica",
+        });
+        let mut content = b"q Q\n".repeat(50);
+        content.extend_from_slice(b"BT /F1 10 Tf 10 10 Td (X) Tj ET\n");
+        let form_id = doc.add_object(Object::Stream(Stream::new(
+            dictionary! {
+                "Type" => "XObject",
+                "Subtype" => "Form",
+                "BBox" => vec![0.into(), 0.into(), 100.into(), 100.into()],
+                "Resources" => dictionary! {
+                    "Font" => dictionary! {
+                        "F1" => Object::Reference(font_id),
+                    },
+                },
+            },
+            content,
+        )));
+
+        let mut budget = FormWalkBudget::with_limits(MAX_FORM_XOBJECT_INVOCATIONS, 10);
+        let items = extract_form(&doc, form_id, &mut budget);
+        assert!(
+            items.is_empty(),
+            "operation budget must stop before the trailing text show"
+        );
+        assert!(budget.was_truncated());
+    }
+
+    #[test]
+    fn page_level_form_dag_stays_within_production_budget() {
+        // A page-level `/Do` of an 8-wide, 6-level Form DAG would expand to
+        // 8^5 = 32_768 leaf drawings without a budget. The production
+        // invocation cap must keep extraction bounded.
+        let (doc, root) = form_dag(8, 6);
+        let (doc, page_id) = page_invoking_form(doc, root);
+
+        let font_cmaps = FontCMaps::from_doc(&doc);
+        let ((items, _, _), _, _, _) = extract_page_text_items(
+            &doc,
+            page_id,
+            1,
+            &font_cmaps,
+            false,
+            &mut FontStyleCache::new(),
+            &mut FormWalkBudget::new(),
+        )
+        .unwrap();
+        assert!(
+            items.len() <= MAX_FORM_XOBJECT_INVOCATIONS,
+            "page-level Form expansion must stay within the invocation cap; got {}",
+            items.len()
+        );
+        assert!(
+            !items.is_empty(),
+            "budget must still allow some nested form text through"
+        );
+    }
+
+    #[test]
+    fn shared_form_budget_spans_two_extraction_passes() {
+        // The invisible-layer retry calls extract_page_text_items twice for
+        // the same page; both passes must share one budget.
+        let (doc, root) = form_dag(1, 2);
+        let (doc, page_id) = page_invoking_form(doc, root);
+        let font_cmaps = FontCMaps::from_doc(&doc);
+        // Root + leaf = 2 invocations on the first pass.
+        let mut budget = FormWalkBudget::with_limits(2, MAX_FORM_XOBJECT_OPERATIONS);
+        let ((first, _, _), _, _, _) = extract_page_text_items(
+            &doc,
+            page_id,
+            1,
+            &font_cmaps,
+            false,
+            &mut FontStyleCache::new(),
+            &mut budget,
+        )
+        .unwrap();
+        assert_eq!(first.iter().filter(|item| item.text == "X").count(), 1);
+        assert!(!budget.was_truncated());
+
+        let ((second, _, _), _, _, _) = extract_page_text_items(
+            &doc,
+            page_id,
+            1,
+            &font_cmaps,
+            true,
+            &mut FontStyleCache::new(),
+            &mut budget,
+        )
+        .unwrap();
+        assert!(
+            second.iter().all(|item| item.text != "X"),
+            "second pass must not get a fresh invocation budget"
+        );
+        assert!(budget.was_truncated());
+    }
+
+    /// Build a document whose page draws *all* of its content through a single
+    /// Form XObject — the shape emitted by print-to-PDF producers like PDFlib,
+    /// where the page stream itself is only `q /X1 Do Q`.
+    fn doc_with_form_content(form_content: &[u8]) -> (Document, ObjectId) {
+        let mut doc = Document::new();
+        let widths: Vec<Object> = (0..=255).map(|_| 600.into()).collect();
+        let font_id = doc.add_object(dictionary! {
+            "Type" => "Font",
+            "Subtype" => "Type1",
+            "BaseFont" => "Helvetica",
+            "FirstChar" => 0,
+            "LastChar" => 255,
+            "Widths" => Object::Array(widths),
+        });
+        let form_id = doc.add_object(Object::Stream(Stream::new(
+            dictionary! {
+                "Type" => "XObject",
+                "Subtype" => "Form",
+                "BBox" => vec![0.into(), 0.into(), 612.into(), 792.into()],
+                "Resources" => dictionary! {
+                    "Font" => dictionary! { "F1" => Object::Reference(font_id) },
+                },
+            },
+            form_content.to_vec(),
+        )));
+        let content_id = doc.add_object(Object::Stream(Stream::new(
+            dictionary! {},
+            b"q /X1 Do Q".to_vec(),
+        )));
+        let page_id = doc.add_object(dictionary! {
+            "Type" => "Page",
+            "Contents" => Object::Reference(content_id),
+            "Resources" => dictionary! {
+                "XObject" => dictionary! { "X1" => Object::Reference(form_id) },
+            },
+            "MediaBox" => vec![0.into(), 0.into(), 612.into(), 792.into()],
+        });
+        let pages_id = doc.add_object(dictionary! {
+            "Type" => "Pages",
+            "Count" => Object::Integer(1),
+            "Kids" => vec![Object::Reference(page_id)],
+        });
+        let catalog_id = doc.add_object(dictionary! {
+            "Type" => "Catalog",
+            "Pages" => Object::Reference(pages_id),
+        });
+        doc.trailer.set("Root", Object::Reference(catalog_id));
+        (doc, page_id)
+    }
+
+    fn form_items(form_content: &[u8]) -> Vec<TextItem> {
+        let (doc, page_id) = doc_with_form_content(form_content);
+        let font_cmaps = FontCMaps::from_doc(&doc);
+        let ((items, _, _), _, _, _) = extract_page_text_items(
+            &doc,
+            page_id,
+            1,
+            &font_cmaps,
+            false,
+            &mut FontStyleCache::new(),
+            &mut FormWalkBudget::new(),
+        )
+        .unwrap();
+        items
+    }
+
+    fn find<'a>(items: &'a [TextItem], text: &str) -> &'a TextItem {
+        items
+            .iter()
+            .find(|item| item.text == text)
+            .unwrap_or_else(|| {
+                let found: Vec<&String> = items.iter().map(|i| &i.text).collect();
+                panic!("no item {text:?} in {found:?}")
+            })
+    }
+
+    #[test]
+    fn t_star_inside_form_moves_to_next_line() {
+        // T* was previously unhandled inside Form XObjects, so every line after
+        // the first piled onto the preceding baseline and drifted right.
+        let items =
+            form_items(b"BT /F1 12 Tf 12 TL 1 0 0 1 100 700 Tm (first) Tj T* (second) Tj ET");
+
+        let first = find(&items, "first");
+        let second = find(&items, "second");
+        assert!((first.y - 700.0).abs() < 0.1, "first y = {}", first.y);
+        assert!((second.y - 688.0).abs() < 0.1, "second y = {}", second.y);
+        assert!((second.x - 100.0).abs() < 0.1, "second x = {}", second.x);
+    }
+
+    #[test]
+    fn td_inside_form_is_relative_to_line_start_not_shown_text() {
+        // Td moves relative to the text *line* matrix. Applying it to the
+        // matrix already advanced by Tj marched each line off the right edge.
+        let items = form_items(b"BT /F1 12 Tf 1 0 0 1 100 700 Tm (AAAAA) Tj 0 -12 Td (B) Tj ET");
+
+        let b = find(&items, "B");
+        assert!((b.x - 100.0).abs() < 0.1, "B x = {} (expected 100)", b.x);
+        assert!((b.y - 688.0).abs() < 0.1, "B y = {}", b.y);
+    }
+
+    #[test]
+    fn td_inside_form_sets_leading_for_later_t_star() {
+        // `TD` sets the leading to -ty as a side effect; a following T* must
+        // reuse it.
+        let items = form_items(
+            b"BT /F1 12 Tf 1 0 0 1 100 700 Tm (one) Tj 0 -15 TD (two) Tj T* (three) Tj ET",
+        );
+
+        assert!((find(&items, "two").y - 685.0).abs() < 0.1);
+        let three = find(&items, "three");
+        assert!((three.y - 670.0).abs() < 0.1, "three y = {}", three.y);
+        assert!((three.x - 100.0).abs() < 0.1, "three x = {}", three.x);
+    }
+
+    #[test]
+    fn quote_operator_inside_form_moves_to_next_line() {
+        let items = form_items(b"BT /F1 12 Tf 12 TL 1 0 0 1 100 700 Tm (first) Tj (second) ' ET");
+
+        let second = find(&items, "second");
+        assert!((second.y - 688.0).abs() < 0.1, "second y = {}", second.y);
+        assert!((second.x - 100.0).abs() < 0.1, "second x = {}", second.x);
+    }
+
+    #[test]
+    fn double_quote_operator_inside_form_sets_spacing_and_moves() {
+        // `aw ac (string) "` — set word spacing and char spacing, then T* and show.
+        let items =
+            form_items(b"BT /F1 12 Tf 12 TL 1 0 0 1 100 700 Tm (first) Tj 0 0 (second) \" ET");
+
+        let second = find(&items, "second");
+        assert!((second.y - 688.0).abs() < 0.1, "second y = {}", second.y);
+        assert!((second.x - 100.0).abs() < 0.1, "second x = {}", second.x);
+    }
+
+    #[test]
+    fn char_spacing_inside_form_widens_advance() {
+        // Tc was hardcoded to 0 in the form parser, so advance widths drifted.
+        // 2 glyphs x 600/1000 x 12pt = 14.4, plus 2 x Tc(2.0) = 18.4.
+        let items = form_items(b"BT /F1 12 Tf 1 0 0 1 100 700 Tm 2 Tc (AB) Tj ET");
+
+        let ab = find(&items, "AB");
+        assert!((ab.width - 18.4).abs() < 0.1, "AB width = {}", ab.width);
+    }
+
+    #[test]
+    fn q_restores_fill_colour_inside_form() {
+        // A white fill set inside q/Q must not leak past the Q — otherwise the
+        // following black text is treated as invisible and dropped entirely.
+        let items = form_items(
+            b"BT /F1 12 Tf 12 TL 1 0 0 1 100 700 Tm q 1 g (hidden) Tj Q T* (visible) Tj ET",
+        );
+
+        assert!(
+            items.iter().any(|item| item.text == "visible"),
+            "text after Q was dropped: {:?}",
+            items.iter().map(|i| &i.text).collect::<Vec<_>>()
+        );
+        assert!(
+            !items.iter().any(|item| item.text == "hidden"),
+            "white-filled text should still be suppressed"
+        );
+    }
+
+    #[test]
+    fn q_restores_text_state_inside_form() {
+        // Tc/TL live in the graphics state; `Q` must roll them back.
+        let items =
+            form_items(b"BT /F1 12 Tf 12 TL 1 0 0 1 100 700 Tm q 30 TL (a) Tj Q T* (b) Tj ET");
+
+        let b = find(&items, "b");
+        assert!(
+            (b.y - 688.0).abs() < 0.1,
+            "b y = {} (leading should restore to 12)",
+            b.y
+        );
+    }
+}

src/lib.rs

@@ -757,6 +757,23 @@ pub struct PageRegionResult {
     pub regions: Vec<RegionText>,
 }
 
+/// Minimum alphanumeric mass an invisible (Tr 3) text layer must carry for
+/// the OCR-layer fallback in [`extract_text_in_regions_mem`] to adopt it. A
+/// real OCR layer carries far more; a stray watermark or artifact does not.
+const OCR_LAYER_MIN_ALNUM: usize = 40;
+
+/// Alphanumeric mass of extracted items, ignoring raster placeholders.
+/// `[Image: ...]` items (ItemType::Image) are synthesized for image
+/// XObjects — they mark that pixels exist, not that text was read, so they
+/// must not count as coverage.
+fn non_placeholder_alnum(items: &[TextItem]) -> usize {
+    items
+        .iter()
+        .filter(|it| !matches!(it.item_type, types::ItemType::Image))
+        .map(|it| it.text.chars().filter(|c| c.is_alphanumeric()).count())
+        .sum()
+}
+
 /// Extract text within bounding-box regions from a PDF in memory.
 ///
 /// This is designed for hybrid OCR pipelines: a layout model detects regions
@@ -809,8 +826,11 @@ pub fn extract_text_in_regions_mem(
         let height = get_page_height(&doc, page_id).unwrap_or(792.0);
         page_heights.insert(*page_num, height);
 
-        // Extract text items for this page
-        let ((mut items, _rects, _lines), has_gid, coords_rotated) =
+        // Extract text items for this page. The Form XObject budget is shared
+        // with the invisible-layer retry below so one page cannot consume two
+        // full expansion budgets.
+        let mut form_budget = extractor::FormWalkBudget::new();
+        let ((mut items, _rects, _lines), mut has_gid, mut coords_rotated, skipped_invisible) =
             extractor::content_stream::extract_page_text_items(
                 &doc,
                 page_id,
@@ -818,7 +838,54 @@ pub fn extract_text_in_regions_mem(
                 &font_cmaps,
                 false,
                 &mut style_cache,
+                &mut form_budget,
             )?;
+        // OCR-layer fallback: scanned pages often carry their text as an
+        // invisible (Tr 3) layer behind the page raster. The visible-only
+        // pass sees nothing there but `[Image: ...]` placeholders, so every
+        // region on the page reports needs_ocr even though the exact text is
+        // embedded in the PDF — and this extractor then disagrees with the
+        // markdown path, which already retries Mixed PDFs with the invisible
+        // layer included. Retry page-scoped, and only when (a) the first
+        // pass actually SKIPPED invisible text — blank pages and image-only
+        // scans without an OCR layer must not pay a second content-stream
+        // parse (review catch) — and (b) the page has NO visible text item
+        // at all (punctuation counts, whitespace-only artifacts don't): an
+        // invisible OCR layer transcribes the raster, so any visible glyph
+        // has an invisible twin there and adoption would duplicate it
+        // (review catches — strict gate, no fuzzy dedupe). Adopt the retry
+        // only when it contributes real, non-garbage text.
+        let has_visible_text = items.iter().any(|it| {
+            !matches!(it.item_type, types::ItemType::Image) && !it.text.trim().is_empty()
+        });
+        if skipped_invisible && !has_visible_text {
+            if let Ok(((inv_items, _inv_rects, _inv_lines), inv_gid, inv_rotated, _)) =
+                extractor::content_stream::extract_page_text_items(
+                    &doc,
+                    page_id,
+                    *page_num,
+                    &font_cmaps,
+                    true,
+                    &mut style_cache,
+                    &mut form_budget,
+                )
+            {
+                let inv_alnum = non_placeholder_alnum(&inv_items);
+                // Judge the WHOLE recovered layer, not a prefix — a broken
+                // OCR layer can hide its garbage past any fixed sample size
+                // (review catch).
+                let sample: String = inv_items
+                    .iter()
+                    .filter(|it| !matches!(it.item_type, types::ItemType::Image))
+                    .map(|it| it.text.as_str())
+                    .collect();
+                if inv_alnum >= OCR_LAYER_MIN_ALNUM && !is_garbage_text(&sample) {
+                    items = inv_items;
+                    has_gid = inv_gid;
+                    coords_rotated = inv_rotated;
+                }
+            }
+        }
         let threshold = text_utils::fix_letterspaced_items(&mut items);
         if threshold > 0.10 {
             page_thresholds.insert(*page_num, threshold);
@@ -975,7 +1042,7 @@ pub fn extract_tables_in_regions_mem(
         let height = get_page_height(&doc, page_id).unwrap_or(792.0);
         page_heights.insert(*page_num, height);
 
-        let ((mut items, rects, lines), has_gid, coords_rotated) =
+        let ((mut items, rects, lines), has_gid, coords_rotated, _skipped_invisible) =
             extractor::content_stream::extract_page_text_items(
                 &doc,
                 page_id,
@@ -983,6 +1050,7 @@ pub fn extract_tables_in_regions_mem(
                 &font_cmaps,
                 false,
                 &mut style_cache,
+                &mut extractor::FormWalkBudget::new(),
             )?;
         let threshold = text_utils::fix_letterspaced_items(&mut items);
         if threshold > 0.10 {
@@ -1286,7 +1354,7 @@ pub fn detect_vector_grid_in_region_mem(
     let needed_pages = HashSet::from([page_1idx]);
     let font_cmaps = FontCMaps::from_doc_pages_fast(&doc, Some(&needed_pages));
     let page_h = get_page_height(&doc, page_id).unwrap_or(792.0);
-    let ((mut items, rects, lines), _has_gid, coords_rotated) =
+    let ((mut items, rects, lines), _has_gid, coords_rotated, _skipped_invisible) =
         extractor::content_stream::extract_page_text_items(
             &doc,
             page_id,
@@ -1294,6 +1362,7 @@ pub fn detect_vector_grid_in_region_mem(
             &font_cmaps,
             false,
             &mut extractor::FontStyleCache::new(),
+            &mut extractor::FormWalkBudget::new(),
         )?;
     text_utils::fix_letterspaced_items(&mut items);
 
@@ -1480,15 +1549,17 @@ mod vector_grid_tests {
         let &page_id = pages.get(&1).unwrap();
         let needed: HashSet<u32> = HashSet::from([1]);
         let cmaps = FontCMaps::from_doc_pages_fast(&doc, Some(&needed));
-        let ((items, rects, _lines), _has_gid, _rotated) = extract_page_text_items(
-            &doc,
-            page_id,
-            1,
-            &cmaps,
-            false,
-            &mut crate::extractor::FontStyleCache::new(),
-        )
-        .unwrap();
+        let ((items, rects, _lines), _has_gid, _rotated, _skipped_invisible) =
+            extract_page_text_items(
+                &doc,
+                page_id,
+                1,
+                &cmaps,
+                false,
+                &mut crate::extractor::FontStyleCache::new(),
+                &mut crate::extractor::FormWalkBudget::new(),
+            )
+            .unwrap();
 
         let (rect_tables, _) = detect_tables_from_rects(&items, &rects, 1);
         assert_eq!(rect_tables.len(), 1, "expected one rect-detected table");
@@ -1522,15 +1593,17 @@ mod vector_grid_tests {
         let &page_id = pages.get(&page_num).unwrap();
         let needed: HashSet<u32> = HashSet::from([page_num]);
         let cmaps = FontCMaps::from_doc_pages_fast(&doc, Some(&needed));
-        let ((items, rects, _lines), _has_gid, _rotated) = extract_page_text_items(
-            &doc,
-            page_id,
-            page_num,
-            &cmaps,
-            false,
-            &mut crate::extractor::FontStyleCache::new(),
-        )
-        .unwrap();
+        let ((items, rects, _lines), _has_gid, _rotated, _skipped_invisible) =
+            extract_page_text_items(
+                &doc,
+                page_id,
+                page_num,
+                &cmaps,
+                false,
+                &mut crate::extractor::FontStyleCache::new(),
+                &mut crate::extractor::FormWalkBudget::new(),
+            )
+            .unwrap();
 
         let (rect_tables, _) = detect_tables_from_rects(&items, &rects, page_num);
         rect_tables
@@ -2258,7 +2331,7 @@ pub fn extract_tables_with_structure_cells_mem(
         let height = get_page_height(&doc, page_id).unwrap_or(792.0);
         page_heights.insert(*page_num, height);
 
-        let ((mut items, _rects, _lines), _has_gid, coords_rotated) =
+        let ((mut items, _rects, _lines), _has_gid, coords_rotated, _skipped_invisible) =
             extractor::content_stream::extract_page_text_items(
                 &doc,
                 page_id,
@@ -2266,6 +2339,7 @@ pub fn extract_tables_with_structure_cells_mem(
                 &font_cmaps,
                 false,
                 &mut style_cache,
+                &mut extractor::FormWalkBudget::new(),
             )?;
         let threshold = text_utils::fix_letterspaced_items(&mut items);
         if threshold > 0.10 {
@@ -3060,7 +3134,7 @@ fn detect_tsr_quality_issue(
     let mut needed: HashSet<u32> = HashSet::new();
     needed.insert(page_1idx);
     let font_cmaps = FontCMaps::from_doc_pages_fast(&doc, Some(&needed));
-    let ((mut items, _rects, _lines), _has_gid, coords_rotated) =
+    let ((mut items, _rects, _lines), _has_gid, coords_rotated, _skipped_invisible) =
         extractor::content_stream::extract_page_text_items(
             &doc,
             page_id,
@@ -3068,6 +3142,7 @@ fn detect_tsr_quality_issue(
             &font_cmaps,
             false,
             &mut extractor::FontStyleCache::new(),
+            &mut extractor::FormWalkBudget::new(),
         )?;
     let adaptive_threshold = text_utils::fix_letterspaced_items(&mut items);
     let coords = if coords_rotated {

tests/integration_tests.rs

@@ -1654,6 +1654,282 @@ fn test_extract_regions_mem_basic_text_pdf() {
     assert_eq!(regions[0].page, 0);
 }
 
+/// Build a synthetic "scanned page" PDF: a full-page image XObject with a
+/// text layer drawn in the given render mode (3 = invisible OCR overlay,
+/// 0 = normal visible fill). `visible_extra` optionally adds a normally
+/// rendered line so double-layer behavior can be tested; `layer_lines`
+/// overrides the layer content (default: three pangram lines);
+/// `quote_ops` shows every layer line via the `'` operator instead of Tj
+/// (both are standard show-text encodings for OCR layers).
+fn make_pdf_with_custom_text_layer(
+    text_render_mode: i32,
+    visible_extra: Option<&str>,
+    layer_lines: Option<&[&str]>,
+    quote_ops: bool,
+) -> Vec<u8> {
+    let mut pdf = b"%PDF-1.4\n".to_vec();
+    let mut offsets = vec![0usize];
+
+    fn add_object(pdf: &mut Vec<u8>, offsets: &mut Vec<usize>, id: usize, body: &str) {
+        offsets.push(pdf.len());
+        pdf.extend_from_slice(format!("{id} 0 obj\n").as_bytes());
+        pdf.extend_from_slice(body.as_bytes());
+        pdf.extend_from_slice(b"\nendobj\n");
+    }
+    fn add_stream_object(
+        pdf: &mut Vec<u8>,
+        offsets: &mut Vec<usize>,
+        id: usize,
+        dict: &str,
+        stream_bytes: &[u8],
+    ) {
+        offsets.push(pdf.len());
+        pdf.extend_from_slice(format!("{id} 0 obj\n").as_bytes());
+        pdf.extend_from_slice(
+            format!("<< {} /Length {} >>\nstream\n", dict, stream_bytes.len()).as_bytes(),
+        );
+        pdf.extend_from_slice(stream_bytes);
+        pdf.extend_from_slice(b"\nendstream\nendobj\n");
+    }
+
+    add_object(
+        &mut pdf,
+        &mut offsets,
+        1,
+        "<< /Type /Catalog /Pages 2 0 R >>",
+    );
+    add_object(
+        &mut pdf,
+        &mut offsets,
+        2,
+        "<< /Type /Pages /Kids [3 0 R] /Count 1 >>",
+    );
+    add_object(
+        &mut pdf,
+        &mut offsets,
+        3,
+        "<< /Type /Page /Parent 2 0 R /MediaBox [0 0 612 792] \
+         /Resources << /Font << /F1 5 0 R >> /XObject << /Im0 6 0 R >> >> \
+         /Contents 4 0 R >>",
+    );
+    // Full-page raster, then the text layer in the requested render mode —
+    // several lines so the OCR-layer gate's alnum floor (40) is well cleared.
+    let mut content = String::from("q 612 0 0 792 0 0 cm /Im0 Do Q\n");
+    let default_layer = [
+        "The quick brown fox jumps over the lazy dog",
+        "Pack my box with five dozen liquor jugs tonight",
+        "Sphinx of black quartz judge my vow carefully",
+    ];
+    let layer: &[&str] = layer_lines.unwrap_or(&default_layer);
+    if quote_ops {
+        // Every line shown via `'` (move-to-next-line + show) — nothing on
+        // this layer goes through Tj, pinning the `'` suppression path.
+        content.push_str(&format!(
+            "BT /F1 12 Tf {text_render_mode} Tr 16 TL 72 716 Td "
+        ));
+        for line in layer {
+            content.push_str(&format!("({line}) ' "));
+        }
+    } else {
+        content.push_str(&format!("BT /F1 12 Tf {text_render_mode} Tr 72 700 Td "));
+        for (i, line) in layer.iter().enumerate() {
+            if i > 0 {
+                content.push_str("0 -16 Td ");
+            }
+            content.push_str(&format!("({line}) Tj "));
+        }
+    }
+    content.push_str("ET\n");
+    if let Some(extra) = visible_extra {
+        content.push_str(&format!("BT /F1 12 Tf 0 Tr 72 500 Td ({extra}) Tj ET\n"));
+    }
+    add_stream_object(&mut pdf, &mut offsets, 4, "", content.as_bytes());
+    add_object(
+        &mut pdf,
+        &mut offsets,
+        5,
+        "<< /Type /Font /Subtype /Type1 /BaseFont /Helvetica >>",
+    );
+    let image_pixel = [128u8];
+    add_stream_object(
+        &mut pdf,
+        &mut offsets,
+        6,
+        "/Type /XObject /Subtype /Image /Width 1 /Height 1 \
+         /ColorSpace /DeviceGray /BitsPerComponent 8",
+        &image_pixel,
+    );
+
+    let xref_start = pdf.len();
+    pdf.extend_from_slice(format!("xref\n0 {}\n", offsets.len()).as_bytes());
+    pdf.extend_from_slice(b"0000000000 65535 f \n");
+    for offset in offsets.iter().skip(1) {
+        pdf.extend_from_slice(format!("{offset:010} 00000 n \n").as_bytes());
+    }
+    pdf.extend_from_slice(
+        format!(
+            "trailer\n<< /Size {} /Root 1 0 R >>\nstartxref\n{}\n%%EOF",
+            offsets.len(),
+            xref_start
+        )
+        .as_bytes(),
+    );
+    pdf
+}
+
+fn make_pdf_with_text_layer(text_render_mode: i32, visible_extra: Option<&str>) -> Vec<u8> {
+    make_pdf_with_custom_text_layer(text_render_mode, visible_extra, None, false)
+}
+
+/// A scanned page whose only text is an invisible (Tr 3) OCR layer behind
+/// the raster must serve that layer from the region extractor instead of
+/// reporting the region as needs_ocr — the exact text is already in the PDF.
+#[test]
+fn test_extract_regions_mem_recovers_invisible_ocr_layer() {
+    let buf = make_pdf_with_text_layer(3, None);
+    let regions = extract_text_in_regions_mem(&buf, &full_page_regions(1)).unwrap();
+    assert_eq!(regions.len(), 1);
+    let region = &regions[0].regions[0];
+    assert!(
+        region.text.contains("quick brown fox"),
+        "invisible OCR layer should be served as region text, got: {:?}",
+        region.text
+    );
+    assert!(
+        !region.needs_ocr,
+        "recovered OCR layer must not fall back to GPU OCR"
+    );
+}
+
+/// ANY visible text on the page — even a single short line — must block the
+/// invisible-layer adoption entirely: the invisible pass returns visible
+/// items too, so adopting it alongside visible text would duplicate the
+/// visible words. Strict zero-visible gate, no fuzzy dedupe.
+#[test]
+fn test_extract_regions_mem_visible_text_blocks_invisible_layer() {
+    let buf = make_pdf_with_text_layer(3, Some("Folio 142"));
+    let regions = extract_text_in_regions_mem(&buf, &full_page_regions(1)).unwrap();
+    let region = &regions[0].regions[0];
+    assert!(
+        region.text.contains("Folio 142"),
+        "visible text should be extracted, got: {:?}",
+        region.text
+    );
+    assert!(
+        !region.text.contains("quick brown fox"),
+        "invisible layer must not be adopted when any visible text exists, got: {:?}",
+        region.text
+    );
+    assert_eq!(
+        region.text.matches("Folio 142").count(),
+        1,
+        "visible text must appear exactly once, got: {:?}",
+        region.text
+    );
+}
+
+/// An invisible OCR layer shown entirely via the `'` show-text operator
+/// (move-to-next-line + show) must also be recovered — the skipped_invisible
+/// signal has to fire on every show-text path, not just Tj/TJ.
+#[test]
+fn test_extract_regions_mem_recovers_quote_operator_layer() {
+    let buf = make_pdf_with_custom_text_layer(3, None, None, true);
+    let regions = extract_text_in_regions_mem(&buf, &full_page_regions(1)).unwrap();
+    let region = &regions[0].regions[0];
+    assert!(
+        region.text.contains("quick brown fox"),
+        "'-operator OCR layer should be recovered, got: {:?}",
+        region.text
+    );
+    assert!(!region.needs_ocr);
+}
+
+/// An invisible layer below the 40-alnum floor (a stray watermark line)
+/// must NOT be adopted — the region keeps its needs_ocr fallback.
+#[test]
+fn test_extract_regions_mem_tiny_invisible_layer_not_adopted() {
+    let buf = make_pdf_with_custom_text_layer(3, None, Some(&["Scanned by ACME"]), false);
+    let regions = extract_text_in_regions_mem(&buf, &full_page_regions(1)).unwrap();
+    let region = &regions[0].regions[0];
+    assert!(
+        !region.text.contains("Scanned by ACME"),
+        "below-floor invisible layer must not be adopted, got: {:?}",
+        region.text
+    );
+    // Only the raster placeholder remains — needs_ocr stays whatever main
+    // reports for placeholder-only regions (false today; downstream
+    // pipelines route placeholder-only text to OCR themselves, and this PR
+    // deliberately does not change that contract).
+    assert!(
+        region.text.trim().starts_with("[Image:"),
+        "region should hold only the raster placeholder, got: {:?}",
+        region.text
+    );
+}
+
+/// An invisible layer that clears the alnum floor but is mostly symbol
+/// garbage (a broken OCR run) must be rejected by the garbage gate.
+#[test]
+fn test_extract_regions_mem_garbage_invisible_layer_not_adopted() {
+    // Each line: 5 alphanumerics among 15 symbol chars. Ten lines clear the
+    // 40-alnum floor (50 alnum) while staying well under the half-alnum
+    // ratio is_garbage_text requires.
+    let garbage_lines: Vec<&str> = vec!["a@@b%%c&&d==e~~"; 10];
+    let buf = make_pdf_with_custom_text_layer(3, None, Some(&garbage_lines), false);
+    let regions = extract_text_in_regions_mem(&buf, &full_page_regions(1)).unwrap();
+    let region = &regions[0].regions[0];
+    assert!(
+        !region.text.contains("a@@b"),
+        "garbage invisible layer must not be adopted, got: {:?}",
+        region.text
+    );
+    assert!(
+        region.text.trim().starts_with("[Image:"),
+        "region should hold only the raster placeholder, got: {:?}",
+        region.text
+    );
+}
+
+/// Punctuation-only visible text (zero alphanumerics) must ALSO block
+/// adoption — the gate is item-presence, not alphanumeric mass. (Real-world
+/// rationale: an invisible OCR layer transcribes the raster, so visible
+/// glyphs typically have invisible twins there; this fixture's layers are
+/// disjoint, so it pins the gate itself, not the duplication scenario.)
+#[test]
+fn test_extract_regions_mem_punctuation_visible_blocks_invisible_layer() {
+    let buf = make_pdf_with_text_layer(3, Some("... --- ..."));
+    let regions = extract_text_in_regions_mem(&buf, &full_page_regions(1)).unwrap();
+    let region = &regions[0].regions[0];
+    assert!(
+        !region.text.contains("quick brown fox"),
+        "invisible layer must not be adopted over punctuation-only visible text, got: {:?}",
+        region.text
+    );
+    assert_eq!(
+        region.text.matches("... --- ...").count(),
+        1,
+        "visible punctuation must be preserved exactly once, got: {:?}",
+        region.text
+    );
+}
+
+/// Regression guard: a normal visible-text page (render mode 0) is served
+/// once and only once — if the fallback ever mis-fired here and merged a
+/// second pass, the phrase would duplicate.
+#[test]
+fn test_extract_regions_mem_visible_layer_unchanged() {
+    let buf = make_pdf_with_text_layer(0, None);
+    let regions = extract_text_in_regions_mem(&buf, &full_page_regions(1)).unwrap();
+    let region = &regions[0].regions[0];
+    assert_eq!(
+        region.text.matches("quick brown fox").count(),
+        1,
+        "visible text must appear exactly once, got: {:?}",
+        region.text
+    );
+    assert!(!region.needs_ocr);
+}
+
 #[test]
 fn test_extract_regions_mem_identity_h_needs_ocr() {
     let buf = std::fs::read("tests/fixtures/shinagawa_identity_h.pdf").unwrap();

wasm/Cargo.lock

@@ -724,7 +724,7 @@ checksum = "d6790f58c7ff633d8771f42965289203411a5e5c68388703c06e14f24770b41e"
 
 [[package]]
 name = "pdf-inspector"
-version = "1.14.0"
+version = "1.14.1"
 dependencies = [
  "env_logger",
  "include_dir",
@@ -740,7 +740,7 @@ dependencies = [
 
 [[package]]
 name = "pdf-inspector-wasm"
-version = "1.14.0"
+version = "1.14.1"
 dependencies = [
  "console_error_panic_hook",
  "js-sys",

wasm/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "pdf-inspector-wasm"
-version = "1.14.0"
+version = "1.14.1"
 edition = "2021"
 authors = ["Firecrawl Team"]
 description = "Browser WebAssembly bindings for pdf-inspector"