// 返回一个 BufferedImage，作为使用从当前已注册 ImageReader 中自动选择的 ImageReader 解码所提供 File 的结果
BufferedImage image=null
try {
image = ImageIO.read(new File(imagepath))
} catch (IOException e) {
System.out.println("读取图片文件出错！"+e.getMessage())
return false
}
// Image Itemp = image.getScaledInstance(300, 300, image.SCALE_SMOOTH)
double Ratio = 0.0
if ((image.getHeight() >300) ||(image.getWidth() >300)) {
if (image.getHeight() >image.getWidth())
//图片要缩放的比例
Ratio = 300.0 / image.getHeight()
else
Ratio = 300.0 / image.getWidth()
}
// 根据仿射转换和插值类型构造一个 AffineTransformOp。
AffineTransformOp op = new AffineTransformOp(AffineTransform
.getScaleInstance(Ratio, Ratio), null)
// 转换源 BufferedImage 并将结果存储在目标 BufferedImage 中。
image = op.filter(image,null)
//image.getScaledInstance(300,300,image.SCALE_SMOOTH)
FileOutputStream out=null
try {
out = new FileOutputStream(newpath)
ImageIO.write((BufferedImage)image,"bmp",out)
out.close()
} catch (Exception e) {
System.out.println("写图片文件出错!!"+e.getMessage())
return false
}
return true
}
package com.hoo.util
import java.awt.Image
import java.awt.image.BufferedImage
import java.io.File
import java.io.FileOutputStream
import java.io.IOException
import java.net.MalformedURLException
import java.net.URL
import javax.imageio.ImageIO
import com.sun.image.codec.jpeg.ImageFormatException
import com.sun.image.codec.jpeg.JPEGCodec
import com.sun.image.codec.jpeg.JPEGEncodeParam
import com.sun.image.codec.jpeg.JPEGImageEncoder
/**
* <b>function:</b> 缩放图片工具类，创建缩略图、伸缩图片比例
* @author hoojo
* @createDate 2012-2-3 上午10:08:47
* @file ScaleImageUtils.java
* @package com.hoo.util
* @version 1.0
*/
public abstract class ScaleImageUtils {
private static final float DEFAULT_SCALE_QUALITY = 1f
private static final String DEFAULT_IMAGE_FORMAT = ".jpg" // 图像文件的格式
private static final String DEFAULT_FILE_PATH = "C:/temp-"
/**
* <b>function:</b> 设置图片压缩质量枚举类；
* Some guidelines: 0.75 high quality、0.5 medium quality、0.25 low quality
* @author hoojo
* @createDate 2012-2-7 上午11:31:45
* @file ScaleImageUtils.java
* @package com.hoo.util
* @project JQueryMobile
* @version 1.0
*/
public enum ImageQuality {
max(1.0f), high(0.75f), medium(0.5f), low(0.25f)
private Float quality
public Float getQuality() {
return this.quality
}
ImageQuality(Float quality) {
this.quality = quality
}
}
private static Image image
/**
* <b>function:</b> 通过目标对象的大小和标准（指定）大小计算出图片缩小的比例
* @author hoojo
* @createDate 2012-2-6 下午04:41:48
* @param targetWidth 目标的宽度
* @param targetHeight 目标的高度
* @param standardWidth 标准（指定）宽度
* @param standardHeight 标准（指定）高度
* @return 最小的合适比例
*/
public static double getScaling(double targetWidth, double targetHeight, double standardWidth, double standardHeight) {
double widthScaling = 0d
double heightScaling = 0d
if (targetWidth > standardWidth) {
widthScaling = standardWidth / (targetWidth * 1.00d)
} else {
widthScaling = 1d
}
if (targetHeight > standardHeight) {
heightScaling = standardHeight / (targetHeight * 1.00d)
} else {
heightScaling = 1d
}
return Math.min(widthScaling, heightScaling)
}
