optimize-image-dir

This command-line tool recursively runs a series of specific image transformation rules on a directory tree containing one or more static images. (At this time, supported formats are JPG, PNG and non-animated GIF.) Any image detected within this directory tree will be converted to PNG if it is a greyscale image, or JPG if it is color, then optimized to reduce file size.

Installation

This command assumes a Unix-like environment, and depends on several other command-line utilities. Install these first:

• ImageMagick (specifcally the convert command).
• Jpegoptim.
• pngquant.

Once all dependencies are installed, you may install this CLI globally with the command

npm install -g optimize-image-dir

Usage

Once installed, run optimize-image-dir {folder name} to process images within a parent folder. For example, if you have a console window open in a directory containing a folder named parent-folder-with-images-in-it, you would run

$ optimize-image-dir parent-folder-with-images-in-it

API

This module can also be used as a dependency of other Node projects. To trigger directory optimization from another JavaScript file in your own node project, npm install optimize-image-dir locally, then import the recursivelyProcessDirectory method:

const { recursivelyProcessDirectory } = require( './index' );

( async () => {
	await recursivelyProcessDirectory( '/abs/path/to/directory' );
} )();

See cli.js for more advanced usage, such as how to display a double progress bar to indicate progress through the first two levels of a directory tree.

License

MIT Licensed.