Overview

On Debian and Ubuntu, the default ImageMagick package is ImageMagick 6, which does not use the magick command. Instead, it relies on classic tools such as:

  • convert
  • identify
  • mogrify

This tutorial focuses exclusively on ImageMagick 6, ensuring compatibility with default Debian/Ubuntu installations.

Installation (Debian / Ubuntu)

sudo apt update
sudo apt install imagemagick

Verify installation:

convert -version

Viewing Image Information

identify image.jpg
identify -verbose image.jpg

Image Conversion

convert input.png output.jpg
convert input.jpg output.png

Batch conversion:

for img in *.png; do
  convert "$img" "${img%.png}.jpg"
done

Resizing Images

convert image.jpg -resize 800x600 resized.jpg
convert image.jpg -resize 800 resized.jpg
convert image.jpg -resize 50% resized.jpg

Cropping Images

convert image.jpg -crop 400x300+100+50 cropped.jpg

Rotating and Flipping

convert image.jpg -rotate 90 rotated.jpg
convert image.jpg -flip flipped.jpg
convert image.jpg -flop flopped.jpg

Adding Text and Watermarks

convert image.jpg -gravity SouthEast -pointsize 24 \
-fill white -annotate +10+10 "Sample Text" output.jpg

Watermark:

convert base.jpg watermark.png -gravity center -composite output.jpg

Adjusting Quality

convert image.jpg -quality 70 compressed.jpg
convert image.jpg -strip optimized.jpg

Convert Images to PDF

convert image.jpg output.pdf
convert *.jpg album.pdf

Batch Editing with Mogrify

mogrify -resize 1024 *.jpg
mogrify -format jpg *.png

⚠️ mogrify edits files in-place.

Security Policy Note

Policy file:

/etc/ImageMagick-6/policy.xml

Modify only if you understand the security implications.

Conclusion

ImageMagick 6 remains a powerful CLI tool on Debian and Ubuntu, ideal for scripting and automation.

References

  • https://imagemagick.org
  • man convert
  • man identify