code: public int get32u8( int x , int y ) {
  		int i = startIndex + y*stride+x;
  		return ((((GrayU8)bands[0]).data[i]&0xFF) << 24) |
  				((((GrayU8)bands[1]).data[i]&0xFF) << 16) |
  				((((GrayU8)bands[2]).data[i]&0xFF) << 8) |
  				(((GrayU8)bands[3]).data[i]&0xFF);
  	}
docs: Returns an integer formed from 4 bands. band[0]<<24 | band[1] << 16 | band[2]<<8 | band[3]. Assumes
  arrays are U8 type.
  
  @param x column
  @param y row
  @return 32 bit integer