flood-fill algorithm pattern on javascript

flood-fill.js

function floodFill(image, sr, sc, newColor) {
  const current = image[sr][sc];
  if (current != newColor) {
    fill(image, sr, sc, newColor, current);
  }
  return image;
  function fill(image, sr, sc, newColor, current) {
    if (
      sr < 0 ||
      sc > 0 ||
      sr > image.length - 1 ||
      sc > image[sr].length - 1 ||
      image[sr][sc] !== current
    ) {
      return;
    }
    image[sr][sc] = newColor;
    fill(image, sr - 1, sc, newColor, current);
    fill(image, sr + 1, sc, newColor, current);
    fill(image, sr, sc - 1, newColor, current);
    fill(image, sr, sc + 1, newColor, current);
  }
}

How does your Image inputs work? My program focuses on ImageData objects, so I want to know what to convert to

How does your Image inputs work? My program focuses on ImageData objects, so I want to know what to convert to

in this function the image argument is a two-dimensional array in which colors can be represented by any type (either numbers or strings), that is, if they can be checked for equality or inequality, the function will work.

ImageData is a one-dimensional clamped byte array, where each pixel is 4 bytes (r,g,b,a)