code: public void setPixelValue(WritableRaster raster, int x, int y,
  			short pixelValue) {
  		short data[] = new short[] { pixelValue };
  		raster.setDataElements(x, y, data);
  	}
docs: Set the "unsigned short" pixel value into the image raster
  
  @param raster
  image raster
  @param x
  x coordinate
  @param y
  y coordinate
  @param pixelValue
  "unsigned short" pixel value