PDF Tools

Name: pdf-tools
Rating: 88
Author: jholhewres

Manipulate PDF files using command-line tools.

Setup

bash

# Ubuntu/Debian
sudo apt install qpdf pdftk ghostscript poppler-utils

# macOS
brew install qpdf pdftk-java ghostscript poppler

Merge PDFs

bash

# Merge multiple PDFs
qpdf --empty --keep-temporary-files page1.pdf page2.pdf page3.pdf -- merged.pdf

# With pdftk
pdftk page1.pdf page2.pdf page3.pdf cat output merged.pdf

# Merge all PDFs in directory
pdftk *.pdf cat output all_merged.pdf

Split PDFs

bash

# Extract pages 1-5
qpdf input.pdf --pages . 1-5 -- output.pdf

# Extract single page
pdftk input.pdf cat 3 output page3.pdf

# Split into individual pages
pdftk input.pdf burst output page_%d.pdf

# Extract range
qpdf input.pdf --pages . 5-10 -- extracted.pdf

Compress PDF

bash

# Compress with Ghostscript (best quality)
gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/ebook \
   -dNOPAUSE -dQUIET -dBATCH -sOutputFile=compressed.pdf input.pdf

# PDF settings options:
# /screen   - 72 dpi, smallest size, lowest quality
# /ebook    - 150 dpi, medium size, good quality
# /printer  - 300 dpi, larger size, high quality
# /prepress - 300 dpi, highest quality

# Quick compress with qpdf
qpdf --compress-streams=y --recompress-flate input.pdf compressed.pdf

Rotate PDF

bash

# Rotate all pages 90 degrees clockwise
pdftk input.pdf cat 1-endright output rotated.pdf

# Rotate specific pages
qpdf input.pdf --rotate=+90:1,3,5 output.pdf

# Rotation options: +90, +180, +270, -90

Add Watermark

bash

# Add text watermark with pdftk
pdftk input.pdf background watermark.pdf output watermarked.pdf

# Create watermark PDF first
echo "DRAFT" | enscript -B -f Courier-Bold100 -o - | ps2pdf - watermark.pdf

Password Protect

bash

# Add password (owner + user)
qpdf --encrypt user_pass owner_pass 256 -- input.pdf protected.pdf

# With pdftk
pdftk input.pdf output protected.pdf encrypt_128bit owner_pw owner_pass user_pw user_pass

Remove Password

bash

# Remove password (requires password)
qpdf --password=yourpass --decrypt protected.pdf unlocked.pdf

# With pdftk
pdftk protected.pdf input_pw yourpass output unlocked.pdf

PDF to Images

bash

# Convert PDF to images (each page)
pdftoppm input.pdf output -png

# Specific page
pdftoppm -f 1 -l 1 input.pdf output -png

# Set resolution (DPI)
pdftoppm -rx 300 -ry 300 input.pdf output -png

Images to PDF

bash

# Convert images to PDF
convert image1.png image2.png output.pdf

# Or with img2pdf (better quality)
img2pdf image1.png image2.png -o output.pdf

Extract Text

bash

# Extract text from PDF
pdftotext input.pdf output.txt

# Keep layout
pdftotext -layout input.pdf output.txt

# Extract from specific pages
pdftotext -f 1 -l 5 input.pdf output.txt

Remove Metadata

bash

# Strip all metadata
qpdf --linearize input.pdf clean.pdf
exiftool -all:all= clean.pdf

# Or with Ghostscript
gs -sDEVICE=pdfwrite -dNOPAUSE -dQUIET -dBATCH \
   -sOutputFile=clean.pdf input.pdf

Tips

•Use qpdf for most operations (faster, more reliable)
•Use pdftk for complex page manipulations
•Use Ghostscript for compression
•Always backup before modifying important PDFs

Triggers

pdf, merge pdf, split pdf, compress pdf, pdf tools, pdf merge, password pdf, watermark pdf