def METHOD_NAME(x, y, image, offset=0.25):
    """Compare two vertical neighbors and add an offset to the smaller one.
    # Arguments
        x: Int. x coordinate of pixel to be compared.
        y: Int. y coordinate of pixel to be compared.
        image: Array.
        offset: Float.
    """
    int_x, int_y = int(x), int(y)
    lower_y = min(int_y + 1, image.shape[1] - 1)
    upper_y = max(int_y - 1, 0)
    if image[int_x, lower_y] > image[int_x, upper_y]:
        y = y + offset
    else:
        y = y - offset
    return y