java 图片切割,缩放,转换类型等等（转）

import java.io.*;
import java.awt.*;
import java.awt.image.*;
import java.awt.Graphics;
import java.awt.color.ColorSpace;
import javax.imageio.ImageIO;

public class ImageCut {

 /**
  * 缩放图像
  *
  * @param srcImageFile
  *            源图像文件地址
  * @param result
  *            缩放后的图像地址
  * @param scale
  *            缩放比例
  * @param flag
  *            缩放选择:true 放大; false 缩小;
  */
 public static void scale(String srcImageFile, String result, int scale,
   boolean flag) {

  try {
   BufferedImage src = ImageIO.read(new File(srcImageFile)); // 读入文件
   int width = src.getWidth(); // 得到源图宽
   int height = src.getHeight(); // 得到源图长
   if (flag) {
    // 放大
    width = width * scale;
    height = height * scale;
   } else {
    // 缩小
    width = width / scale;
    height = height / scale;
   }
   Image image = src.getScaledInstance(width, height,
     Image.SCALE_DEFAULT);

   BufferedImage tag = new BufferedImage(width, height,
     BufferedImage.TYPE_INT_RGB);
   Graphics g = tag.getGraphics();
   g.drawImage(image, 0, 0, null); // 绘制缩小后的图
   g.dispose();
   ImageIO.write(tag, "JPEG", new File(result));// 输出到文件流

  } catch (IOException e) {
   e.printStackTrace();
  }
 }

 /**
  * 图像切割
  *
  * @param srcImageFile
  *            源图像地址
  * @param descDir
  *            切片目标文件夹
  * @param destWidth
  *            目标切片宽度
  * @param destHeight
  *            目标切片高度
  */
 public static void cut(String srcImageFile, String descDir, int destWidth,
   int destHeight) {
  try {
   Image img;
   ImageFilter cropFilter;
   // 读取源图像
   BufferedImage bi = ImageIO.read(new File(srcImageFile));

   int srcWidth = bi.getHeight(); // 源图宽度
   int srcHeight = bi.getWidth(); // 源图高度

   if (srcWidth > destWidth && srcHeight > destHeight) {

    Image image = bi.getScaledInstance(srcWidth, srcHeight,
      Image.SCALE_DEFAULT);

    destWidth = 200; // 切片宽度
    destHeight = 150; // 切片高度

    int cols = 0; // 切片横向数量
    int rows = 0; // 切片纵向数量

    // 计算切片的横向和纵向数量
    if (srcWidth % destWidth == 0) {
     cols = srcWidth / destWidth;
    } else {
     cols = (int) Math.floor(srcWidth / destWidth) + 1;
    }

    if (srcHeight % destHeight == 0) {
     rows = srcHeight / destHeight;
    } else {
     rows = (int) Math.floor(srcHeight / destHeight) + 1;
    }

    // 循环建立切片
    // 改进的想法:是否可用多线程加快切割速度
    for (int i = 0; i < rows; i++) {
     for (int j = 0; j < cols; j++) {
      // 四个参数分别为图像起点坐标和宽高
      // 即: CropImageFilter(int x,int y,int width,int height)

      cropFilter = new CropImageFilter(j * 200, i * 150,
        destWidth, destHeight);

      img = Toolkit.getDefaultToolkit().createImage(
        new FilteredImageSource(image.getSource(),
          cropFilter));

      BufferedImage tag = new BufferedImage(destWidth,
        destHeight, BufferedImage.TYPE_INT_RGB);
      Graphics g = tag.getGraphics();

      g.drawImage(img, 0, 0, null); // 绘制缩小后的图
      g.dispose();
      // 输出为文件
      ImageIO.write(tag, "JPEG", new File(descDir
        + "pre_map_" + i + "_" + j + ".jpg"));
     }
    }
   }
  } catch (Exception e) {
   e.printStackTrace();
  }
 }

 /**
  * 图像类型转换
     * GIF->JPG GIF->PNG PNG->JPG PNG->GIF(X)
     */
 public static void convert(String source, String result) {
  try {
   File f = new File(source);
   f.canRead();
   f.canWrite();
   BufferedImage src = ImageIO.read(f);
   ImageIO.write(src, "JPG", new File(result));
  } catch (Exception e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
 }

 /**
  * 彩色转为黑白
  *
  * @param source
  * @param result
  */
 public static void gray(String source, String result) {
  try {
   BufferedImage src = ImageIO.read(new File(source));
   ColorSpace cs = ColorSpace.getInstance(ColorSpace.CS_GRAY);
   ColorConvertOp op = new ColorConvertOp(cs, null);
   src = op.filter(src, null);
   ImageIO.write(src, "JPEG", new File(result));
  } catch (IOException e) {
   e.printStackTrace();
  }
 }

 /**
  * @param args
  */
 public static void main(String[] args) {
  //cut("e:/1.jpg", "e:/t/", 200, 150);
 }

}