What gets written to the ContaCam temp directory?

[fencepost]

Temp directory gets specified in the Master config, but I'm not sure what gets written there. I was interested in case it's writing temp images for motion detection (using webcams) after managing to exceed the write endurance of a SSD, but I haven't seen any documentation. I have set up a system with a ram drive to use for the temp files, but not sure if it's actually relevant since resource monitor doesn't seem to show anything being written there.