How to process images without resizing in MODx phpthumb?

Question

PHP

I need to process images through phpthumb without resizing and without creating white margins on the sides of the image. I didn't find an answer to my question in the documentation.
These are the settings that now create white margins around the edges.
{
"w": 1080,
"h": 1080,
"q": 95,
"iar": "0",
"ar": "x"
}

Answer 1

"zc":"1",
For images larger than the dimensions specified in the parameters, fits the image on the smaller side of the specified dimensions and crops the larger one to them.