What's TTA mode?

[Architector4]

The readme and the help output from the tool itself have this line:

  -x                   enable tta mode

Yet there seems to be absolutely nothing in the readme, or even any issues opened on this github repo, that ever mention what it is.

Best I found is this issue #28, which only mentions that it's something to do with denoising. This isn't documentation, and still leaves me in the dark on if enabling it does additional denoising passes, or it somehow integrates into the original existing denoising, or how it relates with the -n denoise level switch.

Some kind of an explainer paragraph, like how there are for other settings, would probably be a good idea to add into the readme?