How to display an image using MaixPy API

I would like to display a image like a logo on the Sipeed Maix Dock/Bit using Maix Py API. What is the format that the file needs to be converted and how can it be written to flash and read by MaixPy for displaying. Any sample codes?

The full set of demos seem to be listed here

If I were the admin of this website, I will pin this link where ever possible. Its not easy to find.