code: @Override
  	public void setBand(int x, int y, int band, int value) {
  		if (!isInBounds(x, y))
  			throw new ImageAccessException("Requested pixel is out of bounds.");
  		if (band < 0 || band >= numBands)
  			throw new ImageAccessException("Invalid band requested.");
  
  		data[getIndex(x, y, band)] = value;
  	}
docs: Returns the value of the specified band in the specified pixel.
  
  @param x	 pixel coordinate.
  @param y	 pixel coordinate.
  @param band  which color band in the pixel
  @param value The new value of the element.