| """PDF page rendering (PyMuPDF/fitz) — upfront bulk rendering at ingest time."""
|
| from __future__ import annotations
|
|
|
| from pathlib import Path
|
|
|
| import fitz
|
|
|
| from config import PDF_RENDER_DPI
|
|
|
|
|
| def get_page_count(pdf_path: str) -> int:
|
| """Return the number of pages in a PDF without rendering anything."""
|
| doc = fitz.open(pdf_path)
|
| count = len(doc)
|
| doc.close()
|
| return count
|
|
|
|
|
| def render_pages(pdf_path: str, output_dir: str, dpi: int = PDF_RENDER_DPI) -> int:
|
| """Render every PDF page as a PNG image.
|
|
|
| This is the primary rendering method, called once during PDF ingestion
|
| to pre-render all pages at the configured DPI.
|
| """
|
| out = Path(output_dir)
|
| out.mkdir(parents=True, exist_ok=True)
|
|
|
| doc = fitz.open(pdf_path)
|
| num_pages = len(doc)
|
| zoom = dpi / 72.0
|
| matrix = fitz.Matrix(zoom, zoom)
|
|
|
| for page_num in range(num_pages):
|
| page = doc.load_page(page_num)
|
| pix = page.get_pixmap(matrix=matrix)
|
| img_bytes = pix.tobytes("png")
|
| img_path = out / f"page_{page_num}.png"
|
| with open(img_path, "wb") as f:
|
| f.write(img_bytes)
|
|
|
| doc.close()
|
| return num_pages
|
|
|
|
|
| def render_single_page(
|
| pdf_path: str,
|
| page_num: int,
|
| output_dir: str,
|
| dpi: int = PDF_RENDER_DPI,
|
| ) -> None:
|
| """Render a single PDF page as a PNG and save to disk."""
|
| out = Path(output_dir)
|
| out.mkdir(parents=True, exist_ok=True)
|
|
|
| doc = fitz.open(pdf_path)
|
| zoom = dpi / 72.0
|
| page = doc.load_page(page_num)
|
| pix = page.get_pixmap(matrix=fitz.Matrix(zoom, zoom))
|
| img_path = out / f"page_{page_num}.png"
|
| with open(img_path, "wb") as f:
|
| f.write(pix.tobytes("png"))
|
| doc.close()
|
|
|
|
|
| def extract_page_range_bytes(pdf_path: str, start: int, end: int) -> bytes:
|
| """Extract a range of pages from a PDF and return as in-memory PDF bytes.
|
|
|
| Args:
|
| pdf_path: Path to the source PDF.
|
| start: First page index (0-indexed, inclusive).
|
| end: Last page index (0-indexed, inclusive).
|
|
|
| Returns:
|
| Raw bytes of a new PDF containing only the specified pages.
|
| """
|
| src = fitz.open(pdf_path)
|
| dst = fitz.open()
|
| dst.insert_pdf(src, from_page=start, to_page=end)
|
| pdf_bytes = dst.tobytes()
|
| dst.close()
|
| src.close()
|
| return pdf_bytes
|
|
|
|
|
| def get_page_image_bytes(
|
| page_image_dir: str,
|
| page_num: int,
|
| ) -> bytes:
|
| """Load a pre-rendered page image from disk.
|
|
|
| Pages are expected to already exist from the upfront bulk render
|
| performed during PDF ingestion.
|
| """
|
| path = Path(page_image_dir) / f"page_{page_num}.png"
|
| return path.read_bytes()
|
|
|
