move(x, y = x) {
    const { imageData } = this;

    this.moveTo(
      isUndefined(x) ? x : imageData.x + Number(x),
      isUndefined(y) ? y : imageData.y + Number(y),
    );

    return this;
  }
Move the image with relative offsets.
@param {number} x - The moving distance in the horizontal direction.
@param {number} [y=x] The moving distance in the vertical direction.
@returns {Viewer} this