code: public static byte[] getBufferByteArray(BufferedImage image) {
  		ByteArrayOutputStream os = new ByteArrayOutputStream();
  		try {
  			ImageIO.write(image, "png", os);
  		} catch (IOException e) {
  			logger.error("getBufferByteArray error", e);
  		}
  		return os.toByteArray();
  	}
docs: 通过BufferedImage获取图片byte数组
  
  @param image
  BufferedImage
  @return