Is it possible to provide inpaint mask coordinates to allow drawing mask on front-end side?

[isdemx]

Hello. In /docs swagger I see you have props for img2img requests like
"mask": "string",
"mask_blur": 4,
"inpainting_fill": 0,
"inpaint_full_res": true,
"inpaint_full_res_padding": 0,
"inpainting_mask_invert": 0,
"initial_noise_multiplier": 0,

But how exactly to use them? I want to implement drawing on my FE side to draw mask over the image and the to send it to API.

[missionfloyd]

mask is a base64-encoded black & white image. Affected areas are white, the rest black.