This is a Photoshop script for creating Apple Watch icons from a single large file. It's based on @sponno's iPhone-Photoshop-JSX-Icon-Exporter project.
This script assumes a 1024x1024 source file. Drag the script to the Photoshop icon to run, then select your source file. It creates all files in a subdirectory next to the source file named "generated".
The script generates all the image files listed in the HIG.
This project is maintained by Andrew Wooster. Feel free to send questions my way to @wooster on Twitter.
The iPhone script it's based on has this to say in its readme:
Hope you like this script, hit John Ballinger up on Twitter @sponno on from his website www.bluespark.co.nz
Please keep this Attribution here if you are going to redistrubte this code. Thanks Creative Commons Attribution 3.0 New Zealand License http://creativecommons.org/licenses/by/3.0/nz/