pdf-extract-embedded-images

Extract Embedded Images from PDF

Pull out JPEG and PNG objects embedded in a PDF using pdfimages. Extracts at native resolution without rasterizing the page. Different from pdf-to-images — this recovers the original embedded image files, not a rasterized page render.

When to use

• A PDF is a container for photos (e.g., a photo book or brochure) — you want the original images, not a rasterized version.
• Bulk-extracting image assets from a multi-page document without re-encoding.
• Recovering embedded images at their full embedded resolution and quality.

Inputs to gather

• Input PDF file — path to the PDF. Required.
• Output directory — optional. Default: current directory.

Procedure

1. Check tooling

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

Abort if missing.

2. Validate PDF and inspect contents

file "<input.pdf>"
pdfimages -list "<input.pdf>"

The -list flag shows a summary of embedded images: page number, index, width, height, bits per component, color space, encoding. This helps set expectations (e.g., "3 JPEG images at 2400×3000px").

3. Extract

pdfimages -all "<input.pdf>" "<output-prefix>"

The -all flag extracts both the raw image stream (if JPEG, as .jpg; if PNG, as .png, etc.) plus any alternate-format versions.

Alternatives:

• -j — extract JPEG objects only (faster if there are many PNG/PNG variants).
• -png — convert all images to PNG (may re-encode non-JPEG content; slower but lossy compression converted to lossless).

Recommend -all unless the user specifies otherwise.

4. Report

After extraction:

• Count of images extracted, by type (JPEG, PNG, etc.).
• Output filenames and their dimensions.
• File sizes and whether any extraction failed.
• Remind the user that embedded images may have compression applied by the PDF creator — they are not necessarily at absolute maximum quality, but they are at their native resolution.

Output / side effects

• Image files created with names like prefix-000.jpg, prefix-001.png, etc. (depends on PDF content).
• Original PDF unchanged.

Notes

• Native resolution, not PDF rendering resolution: pdfimages extracts the raw embedded objects at the resolution they were embedded, not the page rendering resolution. For a photo book PDF with 2400×3000px JPEGs embedded, you get those 2400×3000px files directly — much faster and lossless compared to rasterizing the 8.5"×11" page at 300 DPI.
• Lossy source warning: Even though pdfimages does not re-encode, the original embedded images may already be JPEG-compressed by the PDF creator. You cannot recover quality that was lost before embedding. Check output sizes and quality to verify.
• PNG and other formats: pdfimages preserves PNG, TIFF, and other formats within the PDF. The -all flag ensures you get them all. The -png flag is useful if you want everything as PNG but will re-encode and potentially change file size.
• Naming collision: If multiple images have the same name, pdfimages appends sequential suffixes (e.g., prefix-000.jpg, prefix-001.jpg). No files are overwritten.
• Depends: apt install poppler-utils.