TAG

#pdf

9articles

📄The Invisible Text Layer of a Searchable PDF Is Misaligned in Vertical Text — Identifying the Cause (the Source PDF's /Rotate) and Fixing It Without Re-OCR

For a searchable PDF that overlays an OCR invisible text layer on a scanned image, this article identifies the cause of the invisible text drifting on a vertically written document (a double rotation of the coordinate system caused by the source PDF's /Rotate, plus an offset in the line origin) and summarizes how to fix only the invisible text layer without re-running OCR.

2026-07-14

pdfocrpythonpymupdf

📄Fixing Unprintable Scanned PDFs Without Breaking the Invisible Text

For PDFs that overlay invisible OCR text on scanned images, a procedure and verification method for unifying page sizes and making JBIG2 images printable (converting to CCITT G4) without breaking the invisible text — using pikepdf and pypdf instead of Ghostscript. Includes the polarity (black/white inversion) pitfall.

2026-07-08

pdfpythonocrpikepdf