有时候项目中会对图片进行操作，像切图啦，二值化啦，灰度啦。。

在验证码识别的时候很有用

现在将java对图片操作的部分方法写下来

 不管图片如何操作，关键是在new BufferImage 时候的 TYPE

BufferedImage.TYPE_BYTE_GRAY  是灰度化

BufferedImage.TYPE_BYTE_BINARY 是二值化

BufferedImage.TYPE_INT_ARGB ........

详细参数介绍如下：

 

（1） 将地址转换为BufferImage

public static BufferedImage console(String imgUrl) {        BufferedImage img = null;        try {            if (imgUrl.startsWith("http:")) {                img = ImageIO.read(new URL(imgUrl));            } else {                img = ImageIO.read(new File(imgUrl));            }        } catch (MalformedURLException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }         return img;    }

 （2） 图片的灰度化：

public static void huiDuHua(BufferedImage img) {        int sWight = img.getWidth();        int sHight = img.getHeight();        BufferedImage newImage = new BufferedImage(sWight, sHight,                BufferedImage.TYPE_BYTE_GRAY);        for (int x = 0; x < sWight; x++) {            for (int y = 0; y < sHight; y++) {                int rgb= img.getRGB(x, y);                newImage.setRGB(x, y, rgb);            }        }         try {            ImageIO.write(newImage, "jpg", new File("aa.jpg"));        } catch (IOException e) {            e.printStackTrace();        }              }

（3） 图片二值化

public static void erZhiHua(BufferedImage img) {        int sWight = img.getWidth();        int sHight = img.getHeight();        BufferedImage newImage = new BufferedImage(sWight, sHight,                BufferedImage.TYPE_BYTE_BINARY);        for (int x = 0; x < sWight; x++) {            for (int y = 0; y < sHight; y++) {                int rgb= img.getRGB(x, y);                newImage.setRGB(x, y, rgb);            }        }         try {            ImageIO.write(newImage, "jpg", new File("bb.jpg"));        } catch (IOException e) {            e.printStackTrace();        }              }

（4）图片切割

public static BufferedImage cat(int x, int y, int wight, int hight,            BufferedImage img) {        int[] simgRgb = new int[wight * hight];        img.getRGB(x, y, wight, hight, simgRgb, 0, wight);        BufferedImage newImage = new BufferedImage(wight, hight,                BufferedImage.TYPE_INT_ARGB);        newImage.setRGB(0, 0, wight, hight, simgRgb, 0, wight);//         try {//                ImageIO.write(newImage, "PNG", new File("aa.png"));//            } catch (IOException e) {//                // TODO Auto-generated catch block//                e.printStackTrace();//            }          return newImage;    }