This example demonstrates how to set up an LED screen in Macau with dimensions of 15x4 meters.
Open Adobe After Effects (AE)
1. Create a new composition in AE, default resolution 1920x1080:

2. First, uncheck "Scale Lock," then enter the LED's length and width: 15 and 4 respectively.

3. Recheck "Scale Lock" to fix the 15:4 aspect ratio.

4. To ensure video clarity, the video width must be at least 1080p. Changing the video width from 4 to 1080 will automatically calculate the length as 4050.

Finally, you'll get a 4050x1080 composition. Follow this step.