pdf-to-images

Rasterize PDF to Images

Convert PDF pages to raster images (JPEG, PNG, or TIFF) using pdftoppm. Each page becomes a numbered image file. Different from pdf-extract-embedded-images — this rasterizes the entire page content.

When to use

• Converting a scanned PDF or document PDF to standalone images for archival, editing, or distribution.
• Extracting pages as thumbnails or preview images at lower DPI.
• Creating image sequences from a multi-page PDF without needing OCR or text extraction.

Inputs to gather

• Input PDF file — path to the PDF. Required.
• DPI (resolution) — dots per inch. Default: 300 (suitable for archival and print). Ask if the user needs lower DPI for faster processing or smaller file size (e.g., 150 for thumbnails, 600 for high-quality scans).
• Output format — jpeg, png, or tiff. Default: jpeg (good balance of size and quality). PNG for lossless, TIFF for archival.
• Page range (optional) — ask if they want all pages or a subset. If a subset, capture start page and end page (e.g., pages 5–10).
• Output directory — optional. Default: current directory.

Procedure

1. Check tooling

command -v pdftoppm || echo "pdftoppm not installed — install with: sudo apt install poppler-utils"

Abort if missing.

2. Validate PDF

file "<input.pdf>"
pdfinfo "<input.pdf>"  # shows page count, dimensions, etc.

If invalid, abort. Print page count for user awareness.

3. Build command

Base command:

pdftoppm -r <DPI> -<format> "<input.pdf>" "<output-prefix>"

Examples:

• All pages, JPEG at 300 DPI: pdftoppm -r 300 -jpeg input.pdf output_
• Pages 5–10, PNG at 150 DPI: pdftoppm -r 150 -png -f 5 -l 10 input.pdf output_
• All pages, TIFF at 600 DPI: pdftoppm -r 600 -tiff input.pdf output_

Flags:

• -r <DPI> — resolution in DPI.
• -<format> — output format: jpeg, png, tiff.
• -f <N> — first page (optional).
• -l <N> — last page (optional).

4. Execute

pdftoppm -r <DPI> -<format> <page-flags> "<input.pdf>" "<output-prefix>"

Show progress and warn if the PDF is large (many pages or high DPI — processing may take a minute or more).

5. Report

After conversion:

• Count of images created.
• Output directory and filename pattern (e.g., output_001.jpg, output_002.jpg, ...).
• File sizes and total space used.
• If a page range was used, note which pages were extracted.

Output / side effects

• Numbered image files created (e.g., prefix-000001.png). Naming convention depends on pdftoppm version; typically zero-padded 6-digit page numbers.
• Original PDF unchanged.

Notes

• Rasterization vs. embedding: pdftoppm rasterizes the entire page at the specified DPI. This is lossy compared to the original PDF vector content, but suitable for archival, sharing, or thumbnail workflows. See pdf-extract-embedded-images for extracting embedded photos without rasterization.
• DPI guidance: 300 DPI is standard for documents and photos. 150 DPI is adequate for thumbnails or web preview. 600 DPI or higher for fine scanning or print-quality archival.
• Format choice: JPEG for smaller files (good for photos within PDFs). PNG for lossless (documents with text). TIFF for professional archival (larger files, lossless, can embed metadata).
• Large PDFs: Page rasterization is I/O and CPU intensive. A 100-page PDF at 300 DPI can take 1–2 minutes. Warn the user before starting large jobs.
• Depends: apt install poppler-utils.