fix: OCR Track reflow PDF and translation with image text filtering

- Add OCR Track support for reflow PDF generation using raw_ocr_regions.json
- Add OCR Track translation extraction from raw_ocr_regions instead of elements
- Add raw_ocr_translations output format for OCR Track documents
- Add exclusion zone filtering to remove text overlapping with images
- Update API validation to accept both translations and raw_ocr_translations
- Add page_number field to TranslatedItem for proper tracking

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/app/routers/translate.py

@@ -578,7 +578,10 @@ async def download_translated_pdf(
         with open(translation_file, 'r', encoding='utf-8') as f:
             translation_data = json.load(f)
 
-        if not translation_data.get('translations'):
+        # Check for translations (Direct Track) or raw_ocr_translations (OCR Track)
+        has_translations = translation_data.get('translations')
+        has_raw_ocr_translations = translation_data.get('raw_ocr_translations')
+        if not has_translations and not has_raw_ocr_translations:
             raise HTTPException(
                 status_code=status.HTTP_400_BAD_REQUEST,
                 detail="Translation file is empty or incomplete"

backend/app/schemas/translation.py

@@ -146,6 +146,7 @@ class TranslatedItem:
     original_content: str
     translated_content: str
     element_type: str
+    page_number: int = 1
     cell_position: Optional[Tuple[int, int]] = None
 
 

backend/app/services/pdf_generator_service.py

@@ -4701,53 +4701,155 @@ class PDFGeneratorService:
             logger.error(f"Failed to embed image for reflow: {e}")
             return None
 
-    def generate_reflow_pdf(
+    def _collect_exclusion_zones(self, page_data: Dict) -> List[Tuple[float, float, float, float]]:
-        self,
-        json_path: Path,
-        output_path: Path,
-        source_file_path: Optional[Path] = None
-    ) -> bool:
         """
-        Generate reflow layout PDF from OCR/Direct JSON data.
+        Collect exclusion zones (image bboxes) from page elements.
 
-        This creates a flowing document with consistent font sizes,
+        These zones are used to filter out OCR text that overlaps with images,
-        proper reading order, and inline tables/images.
+        preventing text inside images from appearing in reflow PDFs.
 
         Args:
-            json_path: Path to result JSON file (UnifiedDocument format)
+            page_data: Page dictionary containing 'elements'
-            output_path: Path to save generated PDF
-            source_file_path: Optional path to original source file (for images)
 
         Returns:
-            True if successful, False otherwise
+            List of (x0, y0, x1, y1) tuples representing image bounding boxes
         """
-        try:
+        exclusion_zones = []
-            # Load JSON data
-            logger.info(f"Generating reflow PDF from: {json_path}")
-            with open(json_path, 'r', encoding='utf-8') as f:
-                json_data = json.load(f)
 
-            # Get styles
+        elements = page_data.get('elements', [])
-            styles = self._get_reflow_styles()
+        for elem in elements:
+            elem_type = elem.get('type', '')
 
-            # Build document content
+            # Collect image/chart bboxes
-            story = []
+            if elem_type in ('image', 'Image', 'figure', 'Figure', 'chart', 'Chart'):
-            # Use source_file_path if provided (for translated PDFs where JSON is in temp dir)
+                bbox = elem.get('bbox', {})
-            # Otherwise use json_path.parent (for regular reflow PDFs)
+                if isinstance(bbox, dict):
-            if source_file_path and source_file_path.is_dir():
+                    x0 = bbox.get('x0', 0)
-                result_dir = source_file_path
+                    y0 = bbox.get('y0', 0)
-            elif source_file_path and source_file_path.is_file():
+                    x1 = bbox.get('x1', 0)
-                result_dir = source_file_path.parent
+                    y1 = bbox.get('y1', 0)
+                    if x1 > x0 and y1 > y0:
+                        exclusion_zones.append((x0, y0, x1, y1))
+
+            # Collect embedded images in tables
+            if elem_type in ('table', 'Table'):
+                metadata = elem.get('metadata', {})
+                embedded_images = metadata.get('embedded_images', [])
+                for emb_img in embedded_images:
+                    emb_bbox = emb_img.get('bbox', [])
+                    if isinstance(emb_bbox, list) and len(emb_bbox) >= 4:
+                        x0, y0, x1, y1 = emb_bbox[0], emb_bbox[1], emb_bbox[2], emb_bbox[3]
+                        if x1 > x0 and y1 > y0:
+                            exclusion_zones.append((x0, y0, x1, y1))
+
+        return exclusion_zones
+
+    def _is_region_overlapping_exclusion(
+        self,
+        region_bbox: List,
+        exclusion_zones: List[Tuple[float, float, float, float]],
+        ioa_threshold: float = 0.3
+    ) -> bool:
+        """
+        Check if a text region overlaps significantly with any exclusion zone.
+
+        Uses IoA (Intersection over Area) to determine overlap.
+
+        Args:
+            region_bbox: Quadrilateral bbox [[x0,y0], [x1,y1], [x2,y2], [x3,y3]]
+            exclusion_zones: List of (x0, y0, x1, y1) tuples
+            ioa_threshold: Overlap threshold (default 0.3 = 30%)
+
+        Returns:
+            True if region should be excluded
+        """
+        if not exclusion_zones or not region_bbox:
+            return False
+
+        # Convert quadrilateral to rectangular bbox
+        if len(region_bbox) >= 4:
+            xs = [p[0] for p in region_bbox]
+            ys = [p[1] for p in region_bbox]
+            tx0, ty0, tx1, ty1 = min(xs), min(ys), max(xs), max(ys)
         else:
-                result_dir = json_path.parent
+            return False
 
-            # Process each page
+        text_area = (tx1 - tx0) * (ty1 - ty0)
-            pages = json_data.get('pages', [])
+        if text_area <= 0:
-            for page_idx, page_data in enumerate(pages):
+            return False
-                if page_idx > 0:
-                    # Add page break between pages
-                    story.append(Spacer(1, 30))
 
+        for zx0, zy0, zx1, zy1 in exclusion_zones:
+            # Calculate intersection
+            ix0 = max(tx0, zx0)
+            iy0 = max(ty0, zy0)
+            ix1 = min(tx1, zx1)
+            iy1 = min(ty1, zy1)
+
+            if ix1 > ix0 and iy1 > iy0:
+                intersection_area = (ix1 - ix0) * (iy1 - iy0)
+                ioa = intersection_area / text_area
+
+                if ioa >= ioa_threshold:
+                    return True
+
+        return False
+
+    def _filter_regions_by_exclusion(
+        self,
+        regions: List[Dict],
+        exclusion_zones: List[Tuple[float, float, float, float]],
+        ioa_threshold: float = 0.3
+    ) -> List[Dict]:
+        """
+        Filter out text regions that overlap with exclusion zones (images).
+
+        Args:
+            regions: List of raw OCR regions with 'text' and 'bbox'
+            exclusion_zones: List of (x0, y0, x1, y1) tuples
+            ioa_threshold: Overlap threshold
+
+        Returns:
+            Filtered list of regions
+        """
+        if not exclusion_zones:
+            return regions
+
+        filtered = []
+        excluded_count = 0
+
+        for region in regions:
+            bbox = region.get('bbox', [])
+            if self._is_region_overlapping_exclusion(bbox, exclusion_zones, ioa_threshold):
+                excluded_count += 1
+                text = region.get('text', '')[:20]
+                logger.debug(f"Excluding text '{text}...' due to image overlap")
+            else:
+                filtered.append(region)
+
+        if excluded_count > 0:
+            logger.info(f"Filtered {excluded_count} text regions overlapping with images")
+
+        return filtered
+
+    def _render_reflow_elements(
+        self,
+        page_data: Dict,
+        result_dir: Path,
+        styles: Dict,
+        story: List
+    ) -> None:
+        """
+        Render page elements in reflow format (Direct Track logic).
+
+        This method processes elements from the JSON and renders them
+        as flowing content (text, tables, images).
+
+        Args:
+            page_data: Page dictionary containing 'elements'
+            result_dir: Path to result directory for images
+            styles: Style dictionary for paragraphs
+            story: List to append rendered elements to
+        """
         # Get elements in reading order
         elements = self._get_elements_in_reading_order(page_data)
 
@@ -4829,6 +4931,141 @@ class PDFGeneratorService:
                     content = content.replace('&', '&amp;').replace('<', '&lt;').replace('>', '&gt;')
                     story.append(Paragraph(content, styles['Body']))
 
+    def generate_reflow_pdf(
+        self,
+        json_path: Path,
+        output_path: Path,
+        source_file_path: Optional[Path] = None,
+        use_elements_only: bool = False
+    ) -> bool:
+        """
+        Generate reflow layout PDF from OCR/Direct JSON data.
+
+        This creates a flowing document with consistent font sizes,
+        proper reading order, and inline tables/images.
+
+        For OCR Track: Uses raw_ocr_regions.json for text content (ensures all text is included)
+        For Direct Track: Uses content.cells for tables (structured data available)
+
+        Args:
+            json_path: Path to result JSON file (UnifiedDocument format)
+            output_path: Path to save generated PDF
+            source_file_path: Optional path to original source file (for images)
+            use_elements_only: If True, always use elements from JSON (for translated PDFs
+                              where translations are applied to elements, not raw_ocr_regions)
+
+        Returns:
+            True if successful, False otherwise
+        """
+        try:
+            # Load JSON data
+            logger.info(f"Generating reflow PDF from: {json_path}")
+            with open(json_path, 'r', encoding='utf-8') as f:
+                json_data = json.load(f)
+
+            # Detect processing track
+            metadata = json_data.get('metadata', {})
+            processing_track = metadata.get('processing_track', 'direct')
+            is_ocr_track = processing_track == 'ocr'
+            logger.info(f"Reflow PDF generation - Processing track: {processing_track}")
+
+            # Get styles
+            styles = self._get_reflow_styles()
+
+            # Build document content
+            story = []
+            # Use source_file_path if provided (for translated PDFs where JSON is in temp dir)
+            # Otherwise use json_path.parent (for regular reflow PDFs)
+            if source_file_path and source_file_path.is_dir():
+                result_dir = source_file_path
+            elif source_file_path and source_file_path.is_file():
+                result_dir = source_file_path.parent
+            else:
+                result_dir = json_path.parent
+
+            # Extract task_id from result_dir (directory name is the task_id)
+            task_id = result_dir.name
+
+            # Process each page
+            pages = json_data.get('pages', [])
+            for page_idx, page_data in enumerate(pages):
+                page_num = page_idx + 1  # 1-indexed
+                if page_idx > 0:
+                    # Add page break between pages
+                    story.append(Spacer(1, 30))
+
+                # === OCR Track: Use raw_ocr_regions.json for text ===
+                # But for translated PDFs (use_elements_only=True), use elements which have translations applied
+                if is_ocr_track and not use_elements_only and TEXT_REGION_RENDERER_AVAILABLE and load_raw_ocr_regions:
+                    # Load raw OCR regions for this page
+                    raw_regions = load_raw_ocr_regions(str(result_dir), task_id, page_num)
+
+                    if raw_regions:
+                        logger.info(f"OCR Track reflow: Using {len(raw_regions)} raw OCR regions for page {page_num}")
+
+                        # Collect exclusion zones (image bboxes) to filter text inside images
+                        exclusion_zones = self._collect_exclusion_zones(page_data)
+                        if exclusion_zones:
+                            logger.info(f"Collected {len(exclusion_zones)} exclusion zones for text filtering")
+                            raw_regions = self._filter_regions_by_exclusion(raw_regions, exclusion_zones)
+
+                        # Sort by Y coordinate (top to bottom reading order)
+                        def get_y_coord(region):
+                            bbox = region.get('bbox', [])
+                            if bbox and len(bbox) >= 4:
+                                # bbox is [[x0,y0], [x1,y1], [x2,y2], [x3,y3]]
+                                # Get average Y of top-left and top-right corners
+                                return (bbox[0][1] + bbox[1][1]) / 2
+                            return 0
+
+                        sorted_regions = sorted(raw_regions, key=get_y_coord)
+
+                        # Render text blocks as paragraphs
+                        for region in sorted_regions:
+                            text = region.get('text', '')
+                            if text:
+                                text = text.replace('&', '&amp;').replace('<', '&lt;').replace('>', '&gt;')
+                                story.append(Paragraph(text, styles['Body']))
+
+                        # Also render images/charts from elements
+                        elements = self._get_elements_in_reading_order(page_data)
+                        for elem in elements:
+                            elem_type = elem.get('type', elem.get('element_type', ''))
+                            if elem_type in ('image', 'figure', 'Image', 'Figure', 'chart', 'Chart'):
+                                img = self._embed_image_reflow(elem, result_dir)
+                                if img:
+                                    story.append(img)
+                                    story.append(Spacer(1, 8))
+                            # Handle embedded images in tables
+                            elif elem_type in ('table', 'Table'):
+                                elem_metadata = elem.get('metadata', {})
+                                embedded_images = elem_metadata.get('embedded_images', [])
+                                for emb_img in embedded_images:
+                                    img_path_str = emb_img.get('saved_path', '')
+                                    if img_path_str:
+                                        img_path = result_dir / img_path_str
+                                        if not img_path.exists():
+                                            img_path = result_dir / Path(img_path_str).name
+                                        if img_path.exists():
+                                            try:
+                                                img = PlatypusImage(str(img_path))
+                                                max_width = 450
+                                                if img.drawWidth > max_width:
+                                                    ratio = max_width / img.drawWidth
+                                                    img.drawWidth = max_width
+                                                    img.drawHeight *= ratio
+                                                story.append(img)
+                                                story.append(Spacer(1, 8))
+                                            except Exception as e:
+                                                logger.warning(f"Failed to embed table image: {e}")
+                    else:
+                        # Fallback to elements if raw OCR regions not found
+                        logger.warning(f"OCR Track: No raw OCR regions found for page {page_num}, falling back to elements")
+                        self._render_reflow_elements(page_data, result_dir, styles, story)
+                else:
+                    # === Direct Track: Use structured content ===
+                    self._render_reflow_elements(page_data, result_dir, styles, story)
+
             if not story:
                 logger.warning("No content to generate reflow PDF")
                 return False
@@ -4869,6 +5106,9 @@ class PDFGeneratorService:
         merges them to replace original content with translations, and
         generates a PDF with the translated content at original positions.
 
+        For OCR Track: Uses raw_ocr_translations to translate raw OCR regions
+        For Direct Track: Uses translations dict to translate elements
+
         Args:
             result_json_path: Path to original result JSON file (UnifiedDocument format)
             translation_json_path: Path to translation JSON file
@@ -4894,7 +5134,25 @@ class PDFGeneratorService:
             with open(translation_json_path, 'r', encoding='utf-8') as f:
                 translation_json = json.load(f)
 
-            # Extract translations dict from translation JSON
+            # Check if this is OCR Track with raw_ocr_translations
+            raw_ocr_translations = translation_json.get('raw_ocr_translations', [])
+            processing_track = translation_json.get('processing_track', '')
+            target_lang = translation_json.get('target_lang', 'unknown')
+
+            if raw_ocr_translations and processing_track == 'ocr':
+                # OCR Track: Generate PDF using translated raw OCR regions
+                logger.info(
+                    f"Generating translated PDF (OCR Track): {len(raw_ocr_translations)} "
+                    f"raw OCR translations, target_lang={target_lang}"
+                )
+                return self._generate_translated_pdf_ocr_track(
+                    result_json=result_json,
+                    raw_ocr_translations=raw_ocr_translations,
+                    output_path=output_path,
+                    result_dir=result_json_path.parent
+                )
+
+            # Direct Track: Use element-based translations
             translations = translation_json.get('translations', {})
             if not translations:
                 logger.warning("No translations found in translation JSON")
@@ -4908,9 +5166,8 @@ class PDFGeneratorService:
             # Apply translations to result JSON
             translated_doc = apply_translations(result_json, translations)
 
-            target_lang = translation_json.get('target_lang', 'unknown')
             logger.info(
-                f"Generating translated PDF: {len(translations)} translations applied, "
+                f"Generating translated PDF (Direct Track): {len(translations)} translations applied, "
                 f"target_lang={target_lang}"
             )
 
@@ -4927,10 +5184,12 @@ class PDFGeneratorService:
             try:
                 # Use reflow PDF generation for better translated content display
                 # Pass result_json_path.parent as image directory (not the temp file's parent)
+                # use_elements_only=True ensures we use translated elements, not raw_ocr_regions
                 success = self.generate_reflow_pdf(
                     json_path=tmp_path,
                     output_path=output_path,
-                    source_file_path=result_json_path.parent  # Contains extracted images
+                    source_file_path=result_json_path.parent,  # Contains extracted images
+                    use_elements_only=True  # Use elements with translations applied
                 )
                 return success
             finally:
@@ -4950,6 +5209,165 @@ class PDFGeneratorService:
             traceback.print_exc()
             return False
 
+    def _generate_translated_pdf_ocr_track(
+        self,
+        result_json: Dict,
+        raw_ocr_translations: List[Dict],
+        output_path: Path,
+        result_dir: Path
+    ) -> bool:
+        """
+        Generate translated reflow PDF for OCR Track documents.
+
+        Uses raw_ocr_translations to render translated text in reading order.
+
+        Args:
+            result_json: Original result JSON data
+            raw_ocr_translations: List of {page, index, original, translated}
+            output_path: Path to save generated PDF
+            result_dir: Path to result directory for images
+
+        Returns:
+            True if successful, False otherwise
+        """
+        try:
+            # Get styles
+            styles = self._get_reflow_styles()
+
+            # Build document content
+            story = []
+
+            # Build translation lookup: {(page, index): translated_text}
+            translation_lookup: Dict[Tuple[int, int], str] = {}
+            for trans in raw_ocr_translations:
+                page = trans.get('page', 1)
+                idx = trans.get('index', 0)
+                translated = trans.get('translated', '')
+                if translated:
+                    translation_lookup[(page, idx)] = translated
+
+            logger.info(f"Built translation lookup with {len(translation_lookup)} entries")
+
+            # Process each page
+            pages = result_json.get('pages', [])
+            task_id = result_dir.name
+
+            for page_idx, page_data in enumerate(pages):
+                page_num = page_idx + 1  # 1-indexed
+                if page_idx > 0:
+                    # Add page break between pages
+                    story.append(Spacer(1, 30))
+
+                # Load raw OCR regions for this page
+                if TEXT_REGION_RENDERER_AVAILABLE and load_raw_ocr_regions:
+                    raw_regions = load_raw_ocr_regions(str(result_dir), task_id, page_num)
+
+                    if raw_regions:
+                        logger.info(
+                            f"OCR Track translated PDF: Processing {len(raw_regions)} regions "
+                            f"for page {page_num}"
+                        )
+
+                        # Collect exclusion zones (image bboxes) to filter text inside images
+                        exclusion_zones = self._collect_exclusion_zones(page_data)
+
+                        # Sort by Y coordinate (top to bottom reading order)
+                        # Keep original indices for translation lookup
+                        def get_y_coord(region_tuple):
+                            region = region_tuple[1]
+                            bbox = region.get('bbox', [])
+                            if bbox and len(bbox) >= 4:
+                                return (bbox[0][1] + bbox[1][1]) / 2
+                            return 0
+
+                        indexed_regions = list(enumerate(raw_regions))
+                        sorted_regions = sorted(indexed_regions, key=get_y_coord)
+
+                        # Render translated text blocks as paragraphs (skip those overlapping images)
+                        for original_idx, region in sorted_regions:
+                            # Skip regions overlapping with images
+                            bbox = region.get('bbox', [])
+                            if exclusion_zones and self._is_region_overlapping_exclusion(bbox, exclusion_zones):
+                                continue
+                            # Look up translation
+                            translated_text = translation_lookup.get(
+                                (page_num, original_idx),
+                                region.get('text', '')  # Fallback to original
+                            )
+
+                            if translated_text:
+                                # Escape HTML special chars
+                                translated_text = (translated_text
+                                    .replace('&', '&amp;')
+                                    .replace('<', '&lt;')
+                                    .replace('>', '&gt;'))
+                                story.append(Paragraph(translated_text, styles['Body']))
+
+                        # Also render images/charts from elements
+                        elements = self._get_elements_in_reading_order(page_data)
+                        for elem in elements:
+                            elem_type = elem.get('type', elem.get('element_type', ''))
+                            if elem_type in ('image', 'figure', 'Image', 'Figure', 'chart', 'Chart'):
+                                img = self._embed_image_reflow(elem, result_dir)
+                                if img:
+                                    story.append(img)
+                                    story.append(Spacer(1, 8))
+                            # Handle embedded images in tables
+                            elif elem_type in ('table', 'Table'):
+                                elem_metadata = elem.get('metadata', {})
+                                embedded_images = elem_metadata.get('embedded_images', [])
+                                for emb_img in embedded_images:
+                                    img_path_str = emb_img.get('saved_path', '')
+                                    if img_path_str:
+                                        img_path = result_dir / img_path_str
+                                        if not img_path.exists():
+                                            img_path = result_dir / Path(img_path_str).name
+                                        if img_path.exists():
+                                            try:
+                                                img = PlatypusImage(str(img_path))
+                                                max_width = 450
+                                                if img.drawWidth > max_width:
+                                                    ratio = max_width / img.drawWidth
+                                                    img.drawWidth = max_width
+                                                    img.drawHeight *= ratio
+                                                story.append(img)
+                                                story.append(Spacer(1, 8))
+                                            except Exception as e:
+                                                logger.warning(f"Failed to embed table image: {e}")
+                    else:
+                        logger.warning(
+                            f"No raw OCR regions found for page {page_num}, skipping"
+                        )
+
+            if not story:
+                logger.warning("No content to generate translated OCR Track PDF")
+                return False
+
+            # Create PDF document
+            doc = SimpleDocTemplate(
+                str(output_path),
+                pagesize=A4,
+                leftMargin=50,
+                rightMargin=50,
+                topMargin=50,
+                bottomMargin=50
+            )
+
+            # Build PDF
+            doc.build(story)
+
+            logger.info(
+                f"Generated translated OCR Track PDF: {output_path} "
+                f"({output_path.stat().st_size} bytes)"
+            )
+            return True
+
+        except Exception as e:
+            logger.error(f"Failed to generate translated OCR Track PDF: {e}")
+            import traceback
+            traceback.print_exc()
+            return False
+
     def generate_translated_layout_pdf(
         self,
         result_json_path: Path,

backend/app/services/translation_service.py

@@ -233,19 +233,118 @@ class TranslationService:
         self._total_tokens = 0
         self._total_latency = 0.0
 
+    def _load_raw_ocr_regions(
+        self,
+        result_dir: Path,
+        task_id: str,
+        page_num: int
+    ) -> List[Dict]:
+        """
+        Load raw OCR regions for a specific page.
+
+        Args:
+            result_dir: Path to result directory
+            task_id: Task ID
+            page_num: Page number (1-indexed)
+
+        Returns:
+            List of raw OCR region dictionaries with 'text' and 'bbox'
+        """
+        import glob
+
+        # Pattern: {task_id}_*_page_{page_num}_raw_ocr_regions.json
+        pattern = str(result_dir / f"{task_id}_*_page_{page_num}_raw_ocr_regions.json")
+        matches = glob.glob(pattern)
+
+        if not matches:
+            logger.warning(f"No raw OCR regions file found for page {page_num}")
+            return []
+
+        try:
+            with open(matches[0], 'r', encoding='utf-8') as f:
+                regions = json.load(f)
+            logger.info(f"Loaded {len(regions)} raw OCR regions from {matches[0]}")
+            return regions
+        except Exception as e:
+            logger.error(f"Failed to load raw OCR regions: {e}")
+            return []
+
+    def extract_translatable_elements_ocr_track(
+        self,
+        result_json: Dict,
+        result_dir: Path,
+        task_id: str
+    ) -> Tuple[List[TranslatableItem], int]:
+        """
+        Extract translatable elements from raw OCR regions for OCR Track documents.
+
+        Args:
+            result_json: UnifiedDocument JSON data
+            result_dir: Path to result directory
+            task_id: Task ID
+
+        Returns:
+            Tuple of (list of TranslatableItem, total region count)
+        """
+        items = []
+        total_regions = 0
+
+        for page in result_json.get('pages', []):
+            page_number = page.get('page_number', 1)
+
+            # Load raw OCR regions for this page
+            raw_regions = self._load_raw_ocr_regions(result_dir, task_id, page_number)
+
+            for idx, region in enumerate(raw_regions):
+                total_regions += 1
+                text = region.get('text', '').strip()
+
+                if text:
+                    # Use index as element_id for raw OCR regions
+                    items.append(TranslatableItem(
+                        element_id=f"raw_ocr_{page_number}_{idx}",
+                        content=text,
+                        element_type='raw_ocr_region',
+                        page_number=page_number,
+                        cell_position=(idx, 0)  # Store original index in cell_position
+                    ))
+
+        logger.info(
+            f"Extracted {len(items)} translatable items from {total_regions} raw OCR regions (OCR Track)"
+        )
+        return items, total_regions
+
     def extract_translatable_elements(
         self,
-        result_json: Dict
+        result_json: Dict,
+        result_dir: Optional[Path] = None,
+        task_id: Optional[str] = None
     ) -> Tuple[List[TranslatableItem], int]:
         """
         Extract all translatable elements from a result JSON.
 
+        For OCR Track documents, extracts from raw_ocr_regions.json files.
+        For Direct Track documents, extracts from elements in result JSON.
+
         Args:
             result_json: UnifiedDocument JSON data
+            result_dir: Path to result directory (required for OCR Track)
+            task_id: Task ID (required for OCR Track)
 
         Returns:
             Tuple of (list of TranslatableItem, total element count)
         """
+        # Check processing track
+        metadata = result_json.get('metadata', {})
+        processing_track = metadata.get('processing_track', 'direct')
+
+        # For OCR Track, use raw OCR regions
+        if processing_track == 'ocr' and result_dir and task_id:
+            return self.extract_translatable_elements_ocr_track(
+                result_json, result_dir, task_id
+            )
+
+        # For Direct Track, use element-based extraction
         items = []
         total_elements = 0
 
@@ -290,7 +389,7 @@ class TranslationService:
                             ))
 
         logger.info(
-            f"Extracted {len(items)} translatable items from {total_elements} elements"
+            f"Extracted {len(items)} translatable items from {total_elements} elements (Direct Track)"
         )
         return items, total_elements
 
@@ -378,6 +477,7 @@ class TranslationService:
                     original_content=item.content,
                     translated_content=translated_content,
                     element_type=item.element_type,
+                    page_number=item.page_number,
                     cell_position=item.cell_position
                 ))
 
@@ -392,6 +492,7 @@ class TranslationService:
                     original_content=item.content,
                     translated_content=item.content,  # Keep original
                     element_type=item.element_type,
+                    page_number=item.page_number,
                     cell_position=item.cell_position
                 )
                 for item in batch.items
@@ -429,6 +530,7 @@ class TranslationService:
                 original_content=item.content,
                 translated_content=response.translated_text,
                 element_type=item.element_type,
+                page_number=item.page_number,
                 cell_position=item.cell_position
             )
 
@@ -440,6 +542,7 @@ class TranslationService:
                 original_content=item.content,
                 translated_content=item.content,  # Keep original
                 element_type=item.element_type,
+                page_number=item.page_number,
                 cell_position=item.cell_position
             )
 
@@ -451,7 +554,8 @@ class TranslationService:
         target_lang: str,
         total_elements: int,
         processing_time: float,
-        batch_count: int
+        batch_count: int,
+        processing_track: str = 'direct'
     ) -> Dict:
         """
         Build the translation result JSON structure.
@@ -464,13 +568,59 @@ class TranslationService:
             total_elements: Total elements in document
             processing_time: Processing time in seconds
             batch_count: Number of batches used
+            processing_track: 'ocr' or 'direct' - determines output format
 
         Returns:
             Translation result dictionary
         """
-        # Build translations dict
-        translations: Dict[str, Any] = {}
         total_chars = 0
+        is_ocr_track = processing_track == 'ocr'
+
+        if is_ocr_track:
+            # OCR Track: Build raw_ocr_translations list
+            raw_ocr_translations: List[Dict] = []
+
+            for item in translated_items:
+                total_chars += len(item.translated_content)
+
+                if item.element_type == 'raw_ocr_region':
+                    # Extract page and index from element_id: "raw_ocr_{page}_{idx}"
+                    page_num = item.page_number
+                    original_idx = item.cell_position[0] if item.cell_position else 0
+
+                    raw_ocr_translations.append({
+                        'page': page_num,
+                        'index': original_idx,
+                        'original': item.original_content,
+                        'translated': item.translated_content
+                    })
+
+            # Build statistics
+            skipped = total_elements - len(raw_ocr_translations)
+
+            result = {
+                'schema_version': '1.0.0',
+                'source_document': source_document,
+                'source_lang': source_lang,
+                'target_lang': target_lang,
+                'provider': 'dify',
+                'translated_at': datetime.utcnow().isoformat() + 'Z',
+                'processing_track': 'ocr',
+                'statistics': {
+                    'total_elements': total_elements,
+                    'translated_elements': len(raw_ocr_translations),
+                    'skipped_elements': skipped,
+                    'total_characters': total_chars,
+                    'processing_time_seconds': round(processing_time, 2),
+                    'total_tokens': self._total_tokens,
+                    'batch_count': batch_count
+                },
+                'translations': {},  # Empty for OCR Track
+                'raw_ocr_translations': raw_ocr_translations
+            }
+        else:
+            # Direct Track: Build translations dict (existing logic)
+            translations: Dict[str, Any] = {}
 
             for item in translated_items:
                 total_chars += len(item.translated_content)
@@ -548,9 +698,13 @@ class TranslationService:
                 result_json = json.load(f)
 
             source_document = result_json.get('metadata', {}).get('filename', 'unknown')
+            processing_track = result_json.get('metadata', {}).get('processing_track', 'direct')
+            result_dir = result_json_path.parent
 
-            # Extract translatable elements
+            # Extract translatable elements (passes result_dir and task_id for OCR Track)
-            items, total_elements = self.extract_translatable_elements(result_json)
+            items, total_elements = self.extract_translatable_elements(
+                result_json, result_dir, task_id
+            )
 
             if not items:
                 logger.warning("No translatable elements found")
@@ -597,7 +751,8 @@ class TranslationService:
                 target_lang=target_lang,
                 total_elements=total_elements,
                 processing_time=processing_time,
-                batch_count=len(batches)
+                batch_count=len(batches),
+                processing_track=processing_track
             )
 
             # Save result

openspec/changes/archive/2025-12-12-fix-ocr-track-reflow-pdf/proposal.md

@@ -0,0 +1,51 @@
+# Change: Fix OCR Track Reflow PDF
+
+## Why
+
+The OCR Track reflow PDF generation is missing most content because:
+
+1. PP-StructureV3 extracts tables as elements but stores `content: ""` (empty string) instead of structured `content.cells` data
+2. The `generate_reflow_pdf` method expects `content.cells` for tables, so tables are skipped
+3. Table text exists in `raw_ocr_regions.json` (59 text blocks) but is not used by reflow PDF generation
+4. This causes significant content loss - only 6 text elements vs 59 raw OCR regions
+
+The Layout PDF works correctly because it uses `raw_ocr_regions.json` via Simple Text Positioning mode, bypassing the need for structured table data.
+
+## What Changes
+
+### Reflow PDF Generation for OCR Track
+
+Modify `generate_reflow_pdf` to use `raw_ocr_regions.json` as the primary text source for OCR Track documents:
+
+1. **Detect processing track** from JSON metadata
+2. **For OCR Track**: Load `raw_ocr_regions.json` and render all text blocks in reading order
+3. **For Direct Track**: Continue using `content.cells` for tables (already works)
+4. **Images/Charts**: Continue using `content.saved_path` from elements (works for both tracks)
+
+### Data Flow
+
+**OCR Track Reflow PDF (NEW):**
+```
+raw_ocr_regions.json (59 text blocks)
+  + scan_result.json (images/charts only)
+  → Sort by Y coordinate (reading order)
+  → Render text paragraphs + images
+```
+
+**Direct Track Reflow PDF (UNCHANGED):**
+```
+*_result.json (elements with content.cells)
+  → Render tables, text, images in order
+```
+
+## Impact
+
+- **Affected file**: `backend/app/services/pdf_generator_service.py`
+- **User experience**: OCR Track reflow PDF will contain all text content (matching Layout PDF)
+- **Translation**: Reflow translated PDF will also work correctly for OCR Track
+
+## Migration
+
+- No data migration required
+- Existing `raw_ocr_regions.json` files contain all necessary data
+- No API changes

openspec/changes/archive/2025-12-12-fix-ocr-track-reflow-pdf/specs/result-export/spec.md

@@ -0,0 +1,23 @@
+## MODIFIED Requirements
+
+### Requirement: Enhanced PDF Export with Layout Preservation
+
+The PDF export SHALL accurately preserve document layout from both OCR and direct extraction tracks with correct coordinate transformation and multi-page support. For Direct Track, a background image rendering approach SHALL be used for visual fidelity.
+
+#### Scenario: OCR Track reflow PDF uses raw OCR regions
+- **WHEN** generating reflow PDF for an OCR Track document
+- **THEN** the system SHALL load text content from `raw_ocr_regions.json` files
+- **AND** text blocks SHALL be sorted by Y coordinate for reading order
+- **AND** all text content SHALL match the Layout PDF output
+- **AND** images and charts SHALL be embedded from element `saved_path`
+
+#### Scenario: Direct Track reflow PDF uses structured content
+- **WHEN** generating reflow PDF for a Direct Track document
+- **THEN** the system SHALL use `content.cells` for table rendering
+- **AND** text elements SHALL use `content` string directly
+- **AND** images and charts SHALL be embedded from element `saved_path`
+
+#### Scenario: Reflow PDF content consistency
+- **WHEN** comparing Layout PDF and Reflow PDF for the same document
+- **THEN** both PDFs SHALL contain the same text content
+- **AND** only the presentation format SHALL differ (positioned vs flowing)

openspec/changes/archive/2025-12-12-fix-ocr-track-reflow-pdf/tasks.md

@@ -0,0 +1,51 @@
+# Tasks: Fix OCR Track Reflow PDF
+
+## 1. Modify generate_reflow_pdf Method
+
+- [x] 1.1 Add processing track detection
+  - File: `backend/app/services/pdf_generator_service.py`
+  - Location: `generate_reflow_pdf` method (line ~4704)
+  - Read `metadata.processing_track` from JSON data
+  - Branch logic based on track type
+
+- [x] 1.2 Add helper function to load raw OCR regions
+  - File: `backend/app/services/pdf_generator_service.py`
+  - Using existing: `load_raw_ocr_regions` from `text_region_renderer.py`
+  - Pattern: `{task_id}_*_page_{page_num}_raw_ocr_regions.json`
+  - Return: List of text regions with bbox and content
+
+- [x] 1.3 Implement OCR Track reflow rendering
+  - File: `backend/app/services/pdf_generator_service.py`
+  - For OCR Track: Load raw OCR regions per page
+  - Sort text blocks by Y coordinate (top to bottom reading order)
+  - Render text blocks as paragraphs
+  - Still render images/charts from elements
+
+- [x] 1.4 Keep Direct Track logic unchanged
+  - File: `backend/app/services/pdf_generator_service.py`
+  - Direct Track continues using `content.cells` for tables
+  - Extracted to `_render_reflow_elements` helper method
+  - No changes to existing Direct Track flow
+
+## 2. Handle Multi-page Documents
+
+- [x] 2.1 Support per-page raw OCR files
+  - Pattern: `{task_id}_*_page_{page_num}_raw_ocr_regions.json`
+  - Iterate through pages and load corresponding raw OCR file
+  - Handle missing files gracefully (fall back to elements)
+
+## 3. Testing
+
+- [x] 3.1 Test OCR Track reflow PDF
+  - Test with: `a9259180-fc49-4890-8184-2e6d5f4edad3` (scan document)
+  - Verify: All 59 text blocks appear in reflow PDF
+  - Verify: Images are embedded correctly
+
+- [x] 3.2 Test Direct Track reflow PDF
+  - Test with: `1b32428d-0609-4cfd-bc52-56be6956ac2e` (editable PDF)
+  - Verify: Tables render with cells
+  - Verify: No regression from changes
+
+- [x] 3.3 Test translated reflow PDF
+  - Test: Complete translation then download reflow PDF
+  - Verify: Translated text appears correctly

openspec/changes/archive/2025-12-12-fix-ocr-track-translation/proposal.md

@@ -0,0 +1,70 @@
+# Change: Fix OCR Track Translation
+
+## Why
+
+OCR Track translation is missing most content because:
+
+1. Translation service (`extract_translatable_elements`) only processes elements from `scan_result.json`
+2. OCR Track tables have `content: ""` (empty string) - no `content.cells` data
+3. All table text exists in `raw_ocr_regions.json` (59 text blocks) but translation service ignores it
+4. Result: Only 6 text elements translated vs 59 raw OCR regions available
+
+**Current Data Flow (OCR Track):**
+```
+scan_result.json (10 elements, 6 text, 2 empty tables)
+  → Translation extracts 6 text items
+  → 53 text blocks in tables are NOT translated
+```
+
+**Expected Data Flow (OCR Track):**
+```
+raw_ocr_regions.json (59 text blocks)
+  → Translation extracts ALL 59 text items
+  → Complete translation coverage
+```
+
+## What Changes
+
+### 1. Translation Service Enhancement
+
+Modify `translate_document` in `translation_service.py` to:
+
+1. **Detect processing track** from result JSON metadata
+2. **For OCR Track**: Load and translate `raw_ocr_regions.json` instead of elements
+3. **For Direct Track**: Continue using elements with `content.cells` (already works)
+
+### 2. Translation Result Format for OCR Track
+
+Add new field `raw_ocr_translations` to translation JSON for OCR Track:
+
+```json
+{
+  "translations": { ... },  // element-based (for Direct Track)
+  "raw_ocr_translations": [  // NEW: for OCR Track
+    {
+      "index": 0,
+      "original": "华天科技（宝鸡）有限公司",
+      "translated": "Huatian Technology (Baoji) Co., Ltd."
+    },
+    ...
+  ]
+}
+```
+
+### 3. Translated PDF Generation
+
+Modify `generate_translated_pdf` to use `raw_ocr_translations` when available for OCR Track documents.
+
+## Impact
+
+- **Affected files**:
+  - `backend/app/services/translation_service.py` - extraction and translation logic
+  - `backend/app/services/pdf_generator_service.py` - translated PDF rendering
+- **User experience**: OCR Track translations will include ALL text content
+- **API**: Translation JSON format extended (backward compatible)
+
+## Migration
+
+- No data migration required
+- Existing translations continue to work (Direct Track unaffected)
+- Re-translation needed for OCR Track documents to get full coverage

openspec/changes/archive/2025-12-12-fix-ocr-track-translation/specs/translation/spec.md

@@ -0,0 +1,56 @@
+# translation Specification Delta
+
+## MODIFIED Requirements
+
+### Requirement: Translation Content Extraction
+
+The translation service SHALL extract content based on processing track type.
+
+#### Scenario: OCR Track translation extraction
+- **GIVEN** a document processed with OCR Track
+- **AND** the result JSON has `metadata.processing_track = "ocr"`
+- **WHEN** translation service extracts translatable content
+- **THEN** it SHALL load `raw_ocr_regions.json` for each page
+- **AND** it SHALL extract all text blocks from raw OCR regions
+- **AND** it SHALL NOT rely on `content.cells` from table elements
+
+#### Scenario: Direct Track translation extraction (unchanged)
+- **GIVEN** a document processed with Direct Track
+- **AND** the result JSON has `metadata.processing_track = "direct"` or no track specified
+- **WHEN** translation service extracts translatable content
+- **THEN** it SHALL extract from `pages[].elements[]` in result JSON
+- **AND** it SHALL extract table cell content from `content.cells`
+
+### Requirement: Translation Result Format
+
+The translation result JSON SHALL support both element-based and raw OCR translations.
+
+#### Scenario: OCR Track translation result format
+- **GIVEN** an OCR Track document has been translated
+- **WHEN** translation result is saved
+- **THEN** the JSON SHALL include `raw_ocr_translations` array
+- **AND** each item SHALL have `index`, `original`, and `translated` fields
+- **AND** the `translations` object MAY be empty or contain header text translations
+
+#### Scenario: Direct Track translation result format (unchanged)
+- **GIVEN** a Direct Track document has been translated
+- **WHEN** translation result is saved
+- **THEN** the JSON SHALL use `translations` object mapping element_id to translated text
+- **AND** `raw_ocr_translations` field SHALL NOT be present
+
+### Requirement: Translated PDF Generation
+
+The translated PDF generation SHALL use appropriate translation source based on processing track.
+
+#### Scenario: OCR Track translated PDF generation
+- **GIVEN** an OCR Track document with translations
+- **AND** the translation JSON contains `raw_ocr_translations`
+- **WHEN** generating translated reflow PDF
+- **THEN** it SHALL apply translations from `raw_ocr_translations` by index
+- **AND** it SHALL render all translated text blocks in reading order
+
+#### Scenario: Direct Track translated PDF generation (unchanged)
+- **GIVEN** a Direct Track document with translations
+- **WHEN** generating translated reflow PDF
+- **THEN** it SHALL apply translations from `translations` object by element_id
+- **AND** existing behavior SHALL be unchanged

openspec/changes/archive/2025-12-12-fix-ocr-track-translation/tasks.md

@@ -0,0 +1,76 @@
+# Tasks: Fix OCR Track Translation
+
+## 1. Modify Translation Service
+
+- [x] 1.1 Add processing track detection
+  - File: `backend/app/services/translation_service.py`
+  - Location: `translate_document` method
+  - Read `metadata.processing_track` from result JSON
+  - Pass track type to extraction method
+
+- [x] 1.2 Create helper to load raw OCR regions
+  - File: `backend/app/services/translation_service.py`
+  - Function: `_load_raw_ocr_regions(result_dir, task_id, page_num)`
+  - Pattern: `{task_id}_*_page_{page_num}_raw_ocr_regions.json`
+  - Return: List of text regions with index and content
+
+- [x] 1.3 Modify extract_translatable_elements for OCR Track
+  - File: `backend/app/services/translation_service.py`
+  - Added: `extract_translatable_elements_ocr_track` method
+  - Added parameters: `result_dir: Path`, `task_id: str`
+  - For OCR Track: Extract from raw_ocr_regions.json
+  - For Direct Track: Keep existing element-based extraction
+
+- [x] 1.4 Update translation result format
+  - File: `backend/app/services/translation_service.py`
+  - Location: `build_translation_result` method
+  - Added `processing_track` parameter
+  - For OCR Track: Output `raw_ocr_translations` field
+  - Structure: `[{"page": 1, "index": 0, "original": "...", "translated": "..."}]`
+
+## 2. Modify PDF Generation
+
+- [x] 2.1 Update generate_translated_pdf for OCR Track
+  - File: `backend/app/services/pdf_generator_service.py`
+  - Detect `processing_track` and `raw_ocr_translations` from translation JSON
+  - For OCR Track: Call `_generate_translated_pdf_ocr_track`
+  - For Direct Track: Continue using `apply_translations` (element-based)
+
+- [x] 2.2 Create helper to apply raw OCR translations
+  - File: `backend/app/services/pdf_generator_service.py`
+  - Function: `_generate_translated_pdf_ocr_track`
+  - Build translation lookup: `{(page, index): translated_text}`
+  - Load raw OCR regions, sort by Y coordinate
+  - Render translated text with original fallback
+
+## 3. Additional Fixes
+
+- [x] 3.1 Add page_number to TranslatedItem
+  - File: `backend/app/schemas/translation.py`
+  - Added `page_number: int = 1` to TranslatedItem dataclass
+  - Updated `translate_batch` and `translate_item` to pass page_number
+
+- [x] 3.2 Update API endpoint validation
+  - File: `backend/app/routers/translate.py`
+  - Check for both `translations` (Direct Track) and `raw_ocr_translations` (OCR Track)
+
+- [x] 3.3 Filter text overlapping with images
+  - File: `backend/app/services/pdf_generator_service.py`
+  - Added `_collect_exclusion_zones`, `_is_region_overlapping_exclusion`, `_filter_regions_by_exclusion`
+  - Applied filtering in `generate_reflow_pdf` and `_generate_translated_pdf_ocr_track`
+
+## 4. Testing
+
+- [x] 4.1 Test OCR Track translation
+  - Test with: `f8265449-6cb7-425d-a213-5d2e1af73955`
+  - Verify: All 59 text blocks are sent for translation
+  - Verify: Translation JSON contains `raw_ocr_translations`
+
+- [x] 4.2 Test OCR Track translated PDF
+  - Generate translated reflow PDF
+  - Verify: All translated text blocks appear correctly
+  - Verify: Text inside images (like EWsenel) is filtered out
+
+- [x] 4.3 Test Direct Track unchanged
+  - Verify: Translation still uses element-based approach
+  - Verify: No regression in Direct Track flow

openspec/specs/result-export/spec.md

@@ -58,36 +58,23 @@ Export settings (format, thresholds, templates) SHALL apply consistently to V2 t
 
 The PDF export SHALL accurately preserve document layout from both OCR and direct extraction tracks with correct coordinate transformation and multi-page support. For Direct Track, a background image rendering approach SHALL be used for visual fidelity.
 
-#### Scenario: Export PDF from direct extraction track
+#### Scenario: OCR Track reflow PDF uses raw OCR regions
-- **WHEN** exporting PDF from a direct-extraction processed document
+- **WHEN** generating reflow PDF for an OCR Track document
-- **THEN** the system SHALL render source PDF pages as full-page background images at 2x resolution
+- **THEN** the system SHALL load text content from `raw_ocr_regions.json` files
-- **AND** overlay invisible text elements using PDF Text Rendering Mode 3
+- **AND** text blocks SHALL be sorted by Y coordinate for reading order
-- **AND** text SHALL remain selectable and searchable despite being invisible
+- **AND** all text content SHALL match the Layout PDF output
-- **AND** visual output SHALL match source document exactly
+- **AND** images and charts SHALL be embedded from element `saved_path`
 
-#### Scenario: Export PDF from OCR track with full structure
+#### Scenario: Direct Track reflow PDF uses structured content
-- **WHEN** exporting PDF from OCR-processed document
+- **WHEN** generating reflow PDF for a Direct Track document
-- **THEN** the PDF SHALL use all 23 PP-StructureV3 element types
+- **THEN** the system SHALL use `content.cells` for table rendering
-- **AND** render tables with proper cell boundaries
+- **AND** text elements SHALL use `content` string directly
-- **AND** maintain reading order from parsing_res_list
+- **AND** images and charts SHALL be embedded from element `saved_path`
 
-#### Scenario: Handle coordinate transformations correctly
+#### Scenario: Reflow PDF content consistency
-- **WHEN** generating PDF from UnifiedDocument
+- **WHEN** comparing Layout PDF and Reflow PDF for the same document
-- **THEN** system SHALL use explicit page dimensions from OCR results (not inferred from bounding boxes)
+- **THEN** both PDFs SHALL contain the same text content
-- **AND** correctly transform Y-axis coordinates from top-left (OCR) to bottom-left (PDF/ReportLab) origin
+- **AND** only the presentation format SHALL differ (positioned vs flowing)
-- **AND** prevent vertical flipping or position misalignment errors
-
-#### Scenario: Direct Track PDF file size increase
-- **WHEN** generating Layout PDF for Direct Track documents
-- **THEN** the system SHALL accept increased file size due to embedded page images
-- **AND** approximately 1-2 MB per page at 2x resolution is expected
-- **AND** this trade-off is accepted for improved visual fidelity
-
-#### Scenario: Chart elements excluded from text layer
-- **WHEN** generating Layout PDF containing charts
-- **THEN** the system SHALL NOT include chart-internal text in the invisible text layer
-- **AND** chart visuals SHALL be preserved in the background image
-- **AND** chart text SHALL NOT be available for text selection or translation
 
 ### Requirement: Structure Data Export
 The system SHALL provide export formats that preserve document structure for downstream processing.