java图片对比度调整示例代码

 public static void main(String[] args) {  //文件与BufferedImage间的转换  BufferedImage bi=file2img("test.jpg"); //读取图片  BufferedImage bii=img_color_contrast(bi,100);  img2file(bii,"jpg","test1.jpg"); //生成图片 }

//图片对比度调整 public static BufferedImage img_color_contrast(BufferedImage imgsrc, int contrast) {  try {   int contrast_average = 128;   //创建一个不带透明度的图片   BufferedImage back=new BufferedImage(imgsrc.getWidth(), imgsrc.getHeight(),BufferedImage.TYPE_INT_RGB);   int width = imgsrc.getWidth();    int height = imgsrc.getHeight();    int pix;   for (int i = 0; i < height; i++) {     for (int j = 0; j < width; j++) {      int pixel = imgsrc.getRGB(j, i);      Color color = new Color(pixel);     if (color.getRed() < contrast_average)     {      pix = color.getRed()- Math.abs(contrast);      if (pix < 0) pix = 0;     }     else     {      pix = color.getRed() + Math.abs(contrast);      if (pix > 255) pix = 255;     }     int red= pix;     if (color.getGreen() < contrast_average)     {      pix = color.getGreen()- Math.abs(contrast);      if (pix < 0) pix = 0;     }     else     {      pix = color.getGreen() + Math.abs(contrast);      if (pix > 255) pix = 255;     }     int green= pix;      if (color.getBlue() < contrast_average)     {      pix = color.getBlue()- Math.abs(contrast);      if (pix < 0) pix = 0;     }     else     {      pix = color.getBlue() + Math.abs(contrast);      if (pix > 255) pix = 255;     }     int blue= pix;      color = new Color(red,green,blue);     int x=color.getRGB();     back.setRGB(j,i,x);    }   }   return back;  } catch (Exception e) {   e.printStackTrace();   return null;  } }

//读取图片 public static BufferedImage file2img(String imgpath) {  try {   BufferedImage bufferedImage=ImageIO.read(new File(imgpath));   return bufferedImage;  } catch (Exception e) {   e.printStackTrace();   return null;  } } //保存图片,extent为格式，"jpg"、"png"等 public static void img2file(BufferedImage img,String extent,String newfile) {  try {   ImageIO.write(img, extent, new File(newfile));  } catch (Exception e) {   e.printStackTrace();  } }