Creating small screenshots in js using the bmp-js package

Question

In my JS code, I need to save canvas screenshots. I do it with a package bmp-js (https://www.npmjs.com/package/bmp-js)

  data_GUI = await utilities.get_canvas(canvas_selector)
  arr_of_data_GUI = Object.values(data_GUI)
  arr_of_data_GUI = new Uint8Array(arr_of_data_GUI)
  temp = bmp.encode(
    {
      data: arr_of_data_GUI,
      width: canvas_width,
      height: canvas_height
    }
  )
  return fs.createWriteStream(file_path).write(temp.data)

My screenshots are about 3mb in size. I want to take smaller screenshots. The documentation for bmp-js has this code:

var bmp = require("bmp-js");
var rawData = bmp.encode(bmpData);//default no compression,write rawData to .bmp file

The comment to the code says "default no compression", but I can't find how to call this code with compression.

Please help me!