Ⅰ java如何实现把一个大图片压缩到指定大小的图片且长宽比不变
java要实现把一个大图片压缩到指定大小的图片且长宽比不变可以尝试以下操作：
Ⅱ 如何用java 调整jepg图片压缩
ImageWriter writer; // 自己获取 ImageWriter 对象
ImageWriteParam iwp = writer.getDefaultWriteParam();
iwp.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
// 参数为0和1
// 1表示设置最小的压缩以保持最大的图片质量
iwp.setCompressionQuality(1);
File file = new File(OUTPUTFILE);
FileImageOutputStream output = new FileImageOutputStream(file);
writer.setOutput(output);
IIOImage image = new IIOImage(BUFFEREDIMAGE, null, null);
// 写入图片
writer.write(null, image, iwp);
writer.dispose()
问了一下我远标教育的哥们，希望对你有用！
Ⅲ java压缩png图片
您转换的是图片的后缀名吧？您这样的方式已经把图片的信息删除了！
http://sjbbs.zol.com.cn/1/313_9068.html您去下载一个java图片压缩器吧
或者直接在Java下编辑代码来实习转换
package com.sun.util.cyw;
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import javax.imageio.ImageIO;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;
/**
* 图片工具类
* 压缩图片大小
* @author Cyw
* @version 1.0
*/
public class ZIPImage {
private File file = null;
private String outPutFilePath;
private String inPutFilePath;
private String inPutFileName;
private boolean autoBuildFileName;
private String outPutFileName;
private int outPutFileWidth = 100; // 默认输出图片宽
private int outPutFileHeight = 100; // 默认输出图片高
private static boolean isScaleZoom = true; // 是否按比例缩放
public ZIPImage() {
outPutFilePath = "";
inPutFilePath = "";
inPutFileName = "";
autoBuildFileName = true;
outPutFileName = "";
}
/**
*
* @param ipfp
* 源文件夹路径
* @param ipfn
* 源文件名
* @param opfp
* 目标文件路径
* @param opfn
* 目标文件名
*/
public ZIPImage(String ipfp, String ipfn, String opfp, String opfn) {
outPutFilePath = opfp;
inPutFilePath = ipfp;
inPutFileName = ipfn;
autoBuildFileName = true;
outPutFileName = opfn;
}
/**
*
* @param ipfp
* 源文件夹路径
* @param ipfn
* 源文件名
* @param opfp
* 目标文件路径
* @param opfn
* 目标文件名
* @param aBFN
* 是否自动生成目标文件名
*/
public ZIPImage(String ipfp, String ipfn, String opfp, String opfn,
boolean aBFN) {
outPutFilePath = opfp;
inPutFilePath = ipfp;
inPutFileName = ipfn;
autoBuildFileName = aBFN;
outPutFileName = opfn;
}
public boolean isAutoBuildFileName() {
return autoBuildFileName;
}
public void setAutoBuildFileName(boolean autoBuildFileName) {
this.autoBuildFileName = autoBuildFileName;
}
public String getInPutFilePath() {
return inPutFilePath;
}
public void setInPutFilePath(String inPutFilePath) {
this.inPutFilePath = inPutFilePath;
}
public String getOutPutFileName() {
return outPutFileName;
}
public void setOutPutFileName(String outPutFileName) {
this.outPutFileName = outPutFileName;
}
public String getOutPutFilePath() {
return outPutFilePath;
}
public void setOutPutFilePath(String outPutFilePath) {
this.outPutFilePath = outPutFilePath;
}
public int getOutPutFileHeight() {
return outPutFileHeight;
}
public void setOutPutFileHeight(int outPutFileHeight) {
this.outPutFileHeight = outPutFileHeight;
}
public int getOutPutFileWidth() {
return outPutFileWidth;
}
public void setOutPutFileWidth(int outPutFileWidth) {
this.outPutFileWidth = outPutFileWidth;
}
public boolean isScaleZoom() {
return isScaleZoom;
}
public void setScaleZoom(boolean isScaleZoom) {
this.isScaleZoom = isScaleZoom;
}
public String getInPutFileName() {
return inPutFileName;
}
public void setInPutFileName(String inPutFileName) {
this.inPutFileName = inPutFileName;
}
/**
* 压缩图片大小
*
* @return boolean
*/
public boolean compressImage() {
boolean flag = false;
try {
if (inPutFilePath.trim().equals("")) {
throw new NullPointerException("源文件夹路径不存在。");
}
if (inPutFileName.trim().equals("")) {
throw new NullPointerException("图片文件路径不存在。");
}
if (outPutFilePath.trim().equals("")) {
throw new NullPointerException("目标文件夹路径地址为空。");
} else {
if (!ZIPImage.mddir(outPutFilePath)) {
throw new FileNotFoundException(outPutFilePath
+ " 文件夹创建失败！");
}
}
if (this.autoBuildFileName) { // 自动生成文件名
String tempFile[] = getFileNameAndExtName(inPutFileName);
outPutFileName = tempFile[0] + "_cyw." + tempFile[1];
compressPic();
} else {
if (outPutFileName.trim().equals("")) {
throw new NullPointerException("目标文件名为空。");
}
compressPic();
}
} catch (Exception e) {
flag = false;
e.printStackTrace();
return flag;
}
return flag;
}
// 图片处理
private void compressPic() throws Exception {
try {
// 获得源文件
file = new File(inPutFilePath + inPutFileName);
if (!file.exists()) {
throw new FileNotFoundException(inPutFilePath + inPutFileName
+ " 文件不存在！");
}
Image img = ImageIO.read(file);
// 判断图片格式是否正确
if (img.getWidth(null) == -1) {
throw new Exception("文件不可读！");
} else {
int newWidth;
int newHeight;
// 判断是否是等比缩放
if (ZIPImage.isScaleZoom == true) {
// 为等比缩放计算输出的图片宽度及高度
double rate1 = ((double) img.getWidth(null))
/ (double) outPutFileWidth + 0.1;
double rate2 = ((double) img.getHeight(null))
/ (double) outPutFileHeight + 0.1;
// 根据缩放比率大的进行缩放控制
double rate = rate1 > rate2 ? rate1 : rate2;
newWidth = (int) (((double) img.getWidth(null)) / rate);
newHeight = (int) (((double) img.getHeight(null)) / rate);
} else {
newWidth = outPutFileWidth; // 输出的图片宽度
newHeight = outPutFileHeight; // 输出的图片高度
}
BufferedImage tag = new BufferedImage((int) newWidth,
(int) newHeight, BufferedImage.TYPE_INT_RGB);
/*
* Image.SCALE_SMOOTH 的缩略算法 生成缩略图片的平滑度的 优先级比速度高 生成的图片质量比较好 但速度慢
*/
tag.getGraphics().drawImage(
img.getScaledInstance(newWidth, newHeight,
Image.SCALE_SMOOTH), 0, 0, null);
FileOutputStream out = new FileOutputStream(outPutFilePath
+ outPutFileName);
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
encoder.encode(tag);
out.close();
}
} catch (IOException ex) {
ex.printStackTrace();
}
}
/**
* 创建文件夹目录
*
* @param filePath
* @return
* @throws Exception
*/
@SuppressWarnings("unused")
private static boolean mddir(String filePath) throws Exception {
boolean flag = false;
File f = new File(filePath);
if (!f.exists()) {
flag = f.mkdirs();
} else {
flag = true;
}
return flag;
}
/**
* 获得文件名和扩展名
*
* @param fullFileName
* @return
* @throws Exception
*/
private String[] getFileNameAndExtName(String fullFileName)
throws Exception {
String[] fileNames = new String[2];
if (fullFileName.indexOf(".") == -1) {
throw new Exception("源文件名不正确！");
} else {
fileNames[0] = fullFileName.substring(0, fullFileName
.lastIndexOf("."));
fileNames[1] = fullFileName
.substring(fullFileName.lastIndexOf(".") + 1);
}
return fileNames;
}
public Image getSourceImage() throws IOException{
//获得源文件
file = new File(inPutFilePath + inPutFileName);
if (!file.exists()) {
throw new FileNotFoundException(inPutFilePath + inPutFileName
+ " 文件不存在！");
}
Image img = ImageIO.read(file);
return img;
}
/*
* 获得图片大小
* @path ：图片路径
*/
public long getPicSize(String path) {
File file = new File(path);
return file.length();
}
}
//下面是测试程序
package com.sun.util.cyw;
import java.awt.Image;
import java.io.IOException;
public class ImageTest {
public static void main(String[] args) throws IOException {
ZIPImage zip=new ZIPImage("d:\\","1.jpg","d:\\test\\","处理后的图片.jpg",false);
zip.setOutPutFileWidth(1000);
zip.setOutPutFileHeight(1000);
Image image=zip.getSourceImage();
long size=zip.getPicSize("d:\\1.jpg");
System.out.println("处理前的图片大小 width:"+image.getWidth(null));
System.out.println("处理前的图片大小 height:"+image.getHeight(null));
System.out.println("处理前的图片容量:"+ size +" bit");
zip.compressImage();
}
}
Ⅳ java将图片按比例缩小
Image srcImg = ImageIO.read(new FileInputStream(fnSrc) );//取源图
int width = 600; //假设要缩小到600点像素
int height = srcImg.getHeight(null)*600/srcImg.getWidth(null);//按比例，将高度缩减
System.out.println("Width: "+srcImg.getWidth(null));// 这几行是调试用
System.out.println("Height: "+srcImg.getHeight(null));
System.out.println("Width2: "+width);
System.out.println("Height2: "+height);
Image smallImg =srcImg.getScaledInstance(width, height, Image.SCALE_SMOOTH);//缩小
Ⅳ java如何实现压缩图片且保留图片原文件属性，比如拍摄日期
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;public class Zip {
// 压缩
public static void zip(String zipFileName, String inputFile)
throws Exception {
File f = new File(inputFile);
ZipOutputStream out = new ZipOutputStream(new FileOutputStream(
zipFileName));
zip(out, f, null);
System.out.println("zip done");
out.close();
} private static void zip(ZipOutputStream out, File f, String base)
throws Exception {
System.out.println("zipping " + f.getAbsolutePath());
if (f != null && f.isDirectory()) {
File[] fc = f.listFiles();
if (base != null)
out.putNextEntry(new ZipEntry(base + "/"));
base = base == null ? "" : base + "/";
for (int i = 0; i < fc.length; i++) {
zip(out, fc[i], base + fc[i].getName());
}
} else {
out.putNextEntry(new ZipEntry(base));
FileInputStream in = new FileInputStream(f);
int b;
while ((b = in.read()) != -1)
out.write(b);
in.close();
}
} // 解压
public static void unzip(String zipFileName, String outputDirectory)
throws Exception {
ZipInputStream in = new ZipInputStream(new FileInputStream(zipFileName));
ZipEntry z;
while ((z = in.getNextEntry()) != null) {
String name = z.getName();
if (z.isDirectory()) {
name = name.substring(0, name.length() - 1);
File f = new File(outputDirectory + File.separator + name);
f.mkdir();
System.out.println("MD " + outputDirectory + File.separator
+ name);
} else {
System.out.println("unziping " + z.getName());
File f = new File(outputDirectory + File.separator + name);
f.createNewFile();
FileOutputStream out = new FileOutputStream(f);
int b;
while ((b = in.read()) != -1)
out.write(b);
out.close();
}
}
in.close();
} public void deleteFolder(File dir) {
File filelist[] = dir.listFiles();
int listlen = filelist.length;
for (int i = 0; i < listlen; i++) {
if (filelist[i].isDirectory()) {
deleteFolder(filelist[i]);
} else {
filelist[i].delete();
}
}
dir.delete();// 删除当前目录
} public static void main(String[] args) {
try {
// TestZip t = new TestZip();
// t.zip("c:\\test.zip","c:\\test");
// t.unzip("c:\\test.zip","c:\\test2");
} catch (Exception e) {
e.printStackTrace(System.out);
}
}
}
Ⅵ 求一个Java无损压缩图片的示例，把原图片复制到指定目录，按原图比例改变尺寸，不影响图片质量。
图片压缩就是讲图片的内存变小 对象数坑定有印象 你将压缩率改小一点 调整一下压缩率 到自己满意为止
Ⅶ java图片压缩比为1
java压缩图片，按照比例进行压缩
public static void main(String[] args) {
try {
//图片所在路径
BufferedImage templateImage = ImageIO.read(new File("C:\\Users\\晏丁丁\\Pictures\\图片1.png"));
//原始图片的长度和宽度
int height = templateImage.getHeight();
int width = templateImage.getWidth();
//通过比例压缩
float scale = 0.5f;
//通过固定长度压缩
/*int doWithHeight = 100;
int dowithWidth = 300;*/
//压缩段唯之后的轮陆长度和宽度
int doWithHeight = (int) (scale * height);
int dowithWidth = (int) (scale * width);
BufferedImage finalImage = new BufferedImage(dowithWidth, doWithHeight, BufferedImage.TYPE_INT_RGB);
finalImage.getGraphics().drawImage(templateImage.getScaledInstance(dowithWidth, doWithHeight, java.awt.Image.SCALE_SMOOTH), 0, 0, null);
//图片输出路径，以及图握桐培片名
FileOutputStream fileOutputStream = new FileOutputStream("D:/image/tupian.jpg");
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(fileOutputStream);
encoder.encode(finalImage);
fileOutputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
文章知
Ⅷ java如何实现把一个大图片压缩到指定大小的图片且长宽比不变
java要实现把一个大图片压缩到指定大小的图片且长宽比不变可以尝试以下操作：