缩放图像,图像切割,变颜色,转类型

import java.io.*;
import java.awt.*;
import java.awt.image.*;
import java.awt.Graphics;
import java.awt.color.ColorSpace;
import javax.imageio.ImageIO;
/*****************************************************
*
* @author wuzhenzhong
*
* @since 2009-4-14*
*****************************************************/
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("C:/1.jpg", "C:/test/", 200, 150);
}

}