Creating Custom Day/Night Cycle Dynamic Wallpaper for macOS Under 30 Minutes

Published 2020-08-01

7 min read

Note: this post is WIP

Ever since the release of macOS Mojave (macOS 10.14), dynamic wallpapers have become one of my favourite things about the OS aethetics. How it works is that the wallpaper dynamically changes based on current time or sun positions using a set of images, typically taken at the same location with the same viewpoint, but at a different time. These set of images are packed into a single multi-frame .HEIC file with added metadata such as GPS or time information used to determine when to transition to the next image.

Introduction

While traditional “dynamic” wallpapers exist where a folder of images can cycle every set period (30 min, 1 hr, etc.), they don’t work well as they don’t respond corresponding to the environment (such as sunrise and sunsets). Also these wallpapers don’t refresh when the computer is asleep or off, causing the wallpapers to be out of sync once powered on again.

In this post, I will provide a step-by-step guide to creating custom 24-hour cycle (or day/night cycle) dynamic wallpapers for macOS.

macOS Desktop Wallpaper System Preferences

1. Tools and Requirements

To ensure that the dynamic wallpaper can seamlessly transition between images, the day and night time images must be in the same position with the same point of view. One could achieve this by having enough patience to camp outside and take a photo once every few hours.

I don’t have the patience for that. 😑

So instead I will take an existing photo I took as a default day-time image, then use image manipulation programs (e.g. Luminar 4, Photoshop) to edit-in the scene at different times. I use Luminar 4.3 for its recent AI Sky Replacement feature — which uses machine learning to segment skies from other parts of the image. Then the segment mask can be used for a sky substitution. The AI further performs scene relighting in other parts of the image such that the whole image looks convincing — color and light wise.

We will then export each scene as a different image, and upload all of them to a website called Dynamic Wallpaper Club, which will combine all the images into a single multiframe .HEIC file which we can then set as desktop wallpaper in macOS.

2. Using Image Manipulation Programs to Create Scenes

🌤 Part One: Day

🌓 Part Two: Night

🌇 Part Three: Dusk

3. Dynamic Wallpaper Club

The hard work is done. Now it’s time to put them together.

4. Setting the Dynamic Wallpaper

Once the website has processed the wallpaper stack, there is a download button to

Conclusion