export const DISCRETE_LAPLACE_4 = [
  [0, 1, 0],
  [1, -4, 1],
  [0, 1, 0],
];

export const DISCRETE_LAPLACE_8 = [
  [1, 1, 1],
  [1, -8, 1],
  [1, 1, 1],
];

export const SOBEL_X = [
  [-1, 0, 1],
  [-2, 0, 2],
  [-1, 0, 1],
];

export const SOBEL_Y = [
  [-1, -2, -1],
  [0, 0, 0],
  [1, 2, 1],
];

export const SCHARR_X = [
  [3, 0, -3],
  [10, 0, -10],
  [3, 0, -3],
];

export const SCHARR_Y = [
  [3, 10, 3],
  [0, 0, 0],
  [-3, -10, -3],
];

export const PREWITT_X = [
  [1, 0, -1],
  [1, 0, -1],
  [1, 0, -1],
];

export const PREWITT_Y = [
  [1, 1, 1],
  [0, 0, 0],
  [-1, -1, -1],
];

export const ROBERTS_X = [
  [0, 1],
  [-1, 0],
];

export const ROBERTS_Y = [
  [1, 0],
  [0, -1],
];

export const SECOND_DERIVATIVE = [
  [-1, -2, 0, 2, 1],
  [-2, -4, 0, 4, 2],
  [0, 0, 0, 0, 0],
  [1, 2, 0, -2, -1],
  [2, 4, 0, -4, -2],
];

export const SECOND_DERIVATIVE_INV = [
  [1, 2, 0, -2, -1],
  [2, 4, 0, -4, -2],
  [0, 0, 0, 0, 0],
  [-2, -4, 0, 4, 2],
  [-1, -2, 0, 2, 1],
];