Convert PDFs to Pdf-No-Img — Fast MethodsIn many workflows — legal, archival, accessibility, or simply to reduce file size — you may need a version of a PDF that contains only text and other structural elements but no embedded images. “Pdf-No-Img” refers to a PDF where image objects have been removed or replaced, leaving text, vector graphics, annotations, and form fields intact. This article explains why you might need such files, the main approaches to create them, step‑by‑step instructions for popular tools, tips to preserve layout and accessibility, and how to automate the process for batches.
Why create a Pdf-No-Img?
- Smaller file size. Images are often the largest part of a PDF; removing them reduces storage and bandwidth cost.
- Searchability and OCR friendliness. Stripping embedded images can make OCR or text extraction workflows more predictable.
- Privacy and redaction. Images may contain sensitive information (photographs, scanned forms); removing them mitigates exposure.
- Compliance and archiving. Some archives prefer text-only documents for long-term preservation or to meet format guidelines.
- Faster rendering on low-power devices. Less graphical data speeds up viewing on older devices or web previews.
Two main approaches
- Remove image objects from the PDF structure without rasterizing pages — preserves text, vector content, annotations, and form fields.
- Rebuild the PDF by extracting text and vector content into a new document — useful when the original PDF is a scanned image-only file (requires OCR to recover text).
Which approach you choose depends on the original PDF’s nature: born-digital PDFs (with selectable text) are best handled by direct image-object removal; scanned PDFs (images of pages) require OCR-based reconstruction.
Fast methods (tool-based)
Below are fast, practical methods using common tools on different platforms. Each subsection gives concise steps.
Method 1 — qpdf + mutool (command line; preserves structure)
Best when you want to remove embedded images while preserving text and vector objects.
Requirements: qpdf, mupdf-tools (mutool).
Steps:
- Use mutool to inspect objects:
mutool show file.pdf(helps identify image XObjects like /Image or /XObject). - Use a script that traverses page resources and removes image XObjects, or use mutool’s clean/repair features combined with a filter. A simple approach: convert pages to PDF without images by rewriting page content streams replacing Do operators that reference image XObjects with nothing — this typically requires parsing content streams (mutool can dump and rebuild streams).
- Rebuild PDF with qpdf to ensure linearization and repair:
qpdf --recompress-streams --stream-data=decompress input.pdf output.pdf.
Notes: This approach is most precise but technical; scripts in Python (PyPDF2/pypdf or pikepdf) make it easier (see next method).
Method 2 — pikepdf or pypdf (Python; robust and scriptable)
Good for batch processing and integration in pipelines. It manipulates PDF object structure and can remove image XObjects safely.
Requirements: Python 3.x, pikepdf or pypdf.
Example (pikepdf) — remove image XObjects from each page:
import pikepdf def remove_images(src_path, dst_path): with pikepdf.open(src_path) as pdf: for page in pdf.pages: resources = page.get('/Resources') if resources and '/XObject' in resources: xobj = resources['/XObject'] to_delete = [name for name, obj in xobj.items() if obj.get('/Subtype') == '/Image'] for name in to_delete: del xobj[name] pdf.save(dst_path) remove_images('input.pdf', 'output_no_img.pdf') Notes:
- This removes image XObjects referenced by pages. Some PDFs embed images in other ways (inline images in content streams); additional parsing may be needed to remove those.
- Test output to ensure layout remains acceptable.
Method 3 — Ghostscript (command line; raster-based but fast)
Ghostscript can recreate PDFs with images removed by rendering pages as vector-only output, but typically it rasterizes pages which may change text quality. Useful when you accept a rendered output rather than exact object-level preservation.
Command (example):
gs -o output_no_img.pdf -sDEVICE=pdfwrite -dFILTERIMAGE input.pdf Explanation:
- The
-dFILTERIMAGEoption tells Ghostscript to drop image data when producing output. There are related switches like-dFILTERIMAGEand-dFILTERVECTORto control what gets filtered.
Notes:
- Result keeps text as text if Ghostscript can preserve fonts; otherwise pages may be rasterized. Always verify the output for selectable text.
- Very fast and available on most platforms.
Method 4 — Adobe Acrobat Pro (GUI; precise, user-friendly)
If you have Acrobat Pro, it offers a GUI way to remove images or reduce file size.
Steps:
- Open the PDF in Acrobat Pro.
- Choose “Print Production” > “Preflight.”
- Search for fixups like “Remove images” or create a custom preflight profile that deletes image objects.
- Run the fixup and save the result.
Notes:
- Acrobat offers powerful control and preview. Good for one-off or small-batch work when you prefer GUI tools.
Method 5 — OCR + rebuild (for scanned PDFs)
If your PDF is composed of scanned page images, removing images removes all visible content. To create a useful Pdf-No-Img you must extract text using OCR and rebuild a new PDF.
Workflow:
- Run OCR (Tesseract, ABBYY FineReader, Adobe Acrobat OCR) to get text output (plain text, HOCR, ALTO XML).
- Recreate pages using the recognized text layered over blank backgrounds or using PDF creation libraries (ReportLab, wkhtmltopdf, or professional tools) to format text close to original layout.
- Optionally add bookmarks, metadata, and accessibility tags.
Tools:
- Tesseract + Python (pytesseract) for free OCR.
- ABBYY/Adobe for higher accuracy on complex documents.
Notes:
- OCR accuracy determines final quality; expect manual corrections for complex layouts.
Preserving layout, fonts, and accessibility
- Keep fonts: When removing images, ensure embedded fonts remain; otherwise text reflows or substitutes. Libraries like pikepdf preserve font objects by default.
- Accessibility tags: Removing images shouldn’t strip /StructTreeRoot or tags. Verify with accessibility checkers.
- Inline images: Content streams can contain inline image operators (BI/ID/ID/endimage). Tools that only remove XObject references won’t catch these; use a parser (pypdf/pikepdf with raw stream manipulation) to remove them.
- Redaction vs removal: If removing images for privacy, consider redaction tools when image regions must be sanitized (so content can’t be recovered).
Batch processing & automation
- Use pikepdf or pypdf scripts in a loop to process directories.
- Combine with watchdog or cron for automatic watches on incoming folders.
- For high-volume workflows, containerize the script with a small CLI using argparse and deploy on a serverless runner or CI runner.
Example CLI skeleton (Python argparse) — integrates the pikepdf snippet above; add logging and error handling for production.
Verification checklist after conversion
- Is text selectable and searchable where expected?
- Are form fields and annotations preserved?
- Are fonts still embedded or substituted?
- Do resulting file sizes meet expectations?
- Are there leftover inline images or image-like artifacts?
- Run an accessibility validator if needed.
Troubleshooting common issues
- Missing text after removal: You may have removed image-based text (scanned PDF). Use OCR and rebuild.
- Broken layout: Some PDFs use images for layout elements (borders, headings); consider replacing those with vector shapes or reflowing text.
- Residual thumbnails or previews: Some PDFs include embedded preview images as metadata; verify and remove metadata streams if needed.
- Encrypted PDFs: Decrypt (with permission) before processing.
Example use cases
- Legal teams archiving text-only versions for e-discovery.
- Publishers preparing text-first versions for reflowable formats.
- Data extraction pipelines where images interfere with pattern recognition.
- Privacy-sensitive sharing where photographs must be removed.
Conclusion
Creating a Pdf-No-Img can be as simple as running Ghostscript with a filter or as involved as performing object-level edits with pikepdf or pypdf and reconstructing scanned pages with OCR. For most born-digital PDFs, pikepdf offers a reliable, scriptable way to remove image XObjects while preserving text and structure. For scanned PDFs, plan for OCR and careful reconstruction. Choose the method that balances fidelity, speed, and automation for your needs.
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