对图像处理的过程中会遇到一些场景需要将图片反色，反色就是取像素的互补色，比如当前像素是0X00FFFF，对其取反色就是0XFFFFFF – 0X00FFFF = 0XFF0000，依次对图像中的每个像素这样做，最后得到的就是原始图像的反色。

一个对图像取反色的例子：

package bar.ocr;

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;

public class Main_005 {

	public static void main(String[] args) {
		inverseColor("D:\test\ocr\binary_process\woman.jpg", "D:\test\ocr\binary_process\womaninverseColor.jpg");
	}

	public static BufferedImage inverseColor(BufferedImage bufferedImage){

		int width = bufferedImage.getWidth();
		int height = bufferedImage.getHeight();

		BufferedImage resultImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);

		for(int i=0; i<width; i++){
			for(int j=0; j<height; j++){
				int rgb = bufferedImage.getRGB(i, j);
				resultImage.setRGB(i, j, 0XFFFFFF - rgb);
			}
		}

		return resultImage;
	}

	public static boolean inverseColor(String src, String dest){

		BufferedImage srcImage = null;
		try {
			srcImage = ImageIO.read(new File(src));
		} catch (IOException e) {
			e.printStackTrace();
		}

		if(srcImage==null){
			return false;
		}

		BufferedImage destImage = inverseColor(srcImage);
		String extension = dest.substring(dest.lastIndexOf(".")+1);
		try {
			return ImageIO.write(destImage, extension, new File(dest));
		} catch (IOException e) {
			e.printStackTrace();
		}

		return false;
	}

}

反色之前：

反色之后：

.