Resize an image from the Linux terminal

Shrink an image from your terminal with the ImageMagick convert command.
26 readers like this.
How to use digiKam for photo management

Internet Archive Book Images. Modified by Opensource.com. CC BY-SA 4.0

ImageMagick is a handy multipurpose command-line tool for all your image needs. ImageMagick supports a variety of image types, including JPG photos and PNG graphics.

Resizing images

I often use ImageMagick on my webserver to resize images. For example, let's say I want to include a photo of my cats on my personal website. The photo from my phone is very large, about 4000x3000 pixels, at 3.3MB. That's much too large for a web page. I use the ImageMagick convert tool to change the size of my photo so that I can include it on my web page. ImageMagick is a full suite of tools, one of the most common is the convert command.

The ImageMagick convert command uses this general syntax:

convert {input} {actions} {output}

To resize a photo called PXL_20210413_015045733.jpg to a more manageable 500-pixel width, type this:

$ convert PXL_20210413_015045733.jpg -resize 500x sleeping-cats.jpg

The new image is now only 65KB in size. 

You can provide both width and height dimensions with the -resize option. But, by providing only the width, ImageMagic does the math for you and automatically retains the aspect ratio by resizing the output image with a proportional height.

Install ImageMagick on Linux

On Linux, you can install ImageMagick using your package manager. For instance, on Fedora or similar:

$ sudo dnf install imagemagick

On Debian and similar:

$ sudo apt install imagemagick

On macOS, use MacPorts or Homebrew.

On Windows, use Chocolatey.

What to read next
photo of Jim Hall
Jim Hall is an open source software advocate and developer, best known for usability testing in GNOME and as the founder + project coordinator of FreeDOS.

Comments are closed.

Creative Commons LicenseThis work is licensed under a Creative Commons Attribution-Share Alike 4.0 International License.