java壓縮圖片代碼

『壹』 java 圖片的壓縮

前面是轉成JPG再轉出

後面是直接輸出

『貳』 Java壓縮圖片ImageIO.read()報錯

BufferedImage sourceImg =ImageIO.read(new FileInputStream(new File(toPath)));

或者

BufferedImage sourceImg =ImageIO.read(new File(toPath));

『叄』 java如何實現把一個大圖片壓縮到指定大小的圖片且長寬比不變

java要實現把一個大圖片壓縮到指定大小的圖片且長寬比不變可以嘗試以下操作：

『肆』 java代碼查看壓縮文件下的圖片

LZ 可以看看 commons-compress ，可以解 zip gz bzip2 等壓縮格式

『伍』 java 圖片縮放代碼

直接給你一個類，直接套用就好了

import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.awt.image.ColorModel;
import java.awt.image.WritableRaster;
import java.io.File;

import javax.imageio.ImageIO;

public class Resize {
BufferedImage bufImage;
int width;
int height;

public Resize() {
// TODO Auto-generated constructor stub
}

public Resize(String srcPath,int width,int height) {
this.width = width;
this.height = height;
try{
this.bufImage = ImageIO.read(new File(srcPath));
}catch(Exception e){
e.printStackTrace();
}
}

public static BufferedImage rize(BufferedImage srcBufImage,int width,int height){

BufferedImage bufTarget = null;

double sx = (double) width / srcBufImage.getWidth();
double sy = (double) height / srcBufImage.getHeight();

int type = srcBufImage.getType();
if(type == BufferedImage.TYPE_CUSTOM){
ColorModel cm = srcBufImage.getColorModel();
WritableRaster raster = cm.(width,
height);
boolean alphaPremultiplied = cm.isAlphaPremultiplied();
bufTarget = new BufferedImage(cm, raster, alphaPremultiplied, null);
}else
bufTarget = new BufferedImage(width, height, type);

Graphics2D g = bufTarget.createGraphics();
g.setRenderingHint(RenderingHints.KEY_RENDERING,
RenderingHints.VALUE_RENDER_QUALITY);
g.drawRenderedImage(srcBufImage, AffineTransform.getScaleInstance(sx, sy));
g.dispose();
return bufTarget;
}

}

『陸』 JAVA與圖像壓縮

此篇轉載。
----------------------------------------------------------------------
下面是一段給圖片加上網站logo的代碼，注意第12，13，14行設置了圖片的壓縮比。本例為不壓縮原圖片。

java 代碼

BufferedImage image = ImageIO.read(new FileInputStream("c:\\base.jpg"));
//讀取圖標
BufferedImage image_biao = ImageIO.read(new FileInputStream(
"c:\\logo.gif"));
Graphics2D g = image.createGraphics();
g.drawImage(image_biao, 10, 10, image_biao.getWidth(null),
image_biao.getHeight(null), null);
g.dispose();
FileOutputStream out = new FileOutputStream("c:\\out.jpg");

JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
JPEGEncodeParam param = encoder.getDefaultJPEGEncodeParam(image);
param.setQuality(1f, false);
encoder.setJPEGEncodeParam(param);
encoder.encode(image);
out.close();

setQuality

public void setQuality(float quality, boolean forceBaseline)

quality取值在 1.0 到 0.0 之間

Some guidelines: 0.75 high quality 0.5 medium quality 0.25 low quality

另外要得到一張指定高度和寬度的圖片的話可以用以下代碼：(接上面代碼)

java 代碼

BufferedImage tag = new BufferedImage(500, 300,image.getType());
tag.getGraphics().drawImage(image, 0, 0, 500, 300, null); //繪制縮小後的圖

FileOutputStream out2 = new FileOutputStream("c:\\out2.jpg");

JPEGImageEncoder encoder2 = JPEGCodec.createJPEGEncoder(out2);
JPEGEncodeParam param2 = encoder.getDefaultJPEGEncodeParam(tag);
param2.setQuality(1f, false);
encoder2.setJPEGEncodeParam(param2);
encoder2.encode(tag);
out2.close();

注意第一行新建 BufferedImage 的時候要使用原圖片的type，這樣可以保證輸出與原圖片相同質量的圖片。

『柒』 java代碼能否實現圖片的高度寬度的壓縮，但像素不變

不可能啊，高度和寬度任何一個元素變化，都會導致像素變化的。。

『捌』 java壓縮png圖片

您轉換的是圖片的後綴名吧？您這樣的方式已經把圖片的信息刪除了！
http://sjbbs.zol.com.cn/1/313_9068.html您去下載一個java圖片壓縮器吧
或者直接在Java下編輯代碼來實習轉換
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;

/**
* 圖片工具類
* 壓縮圖片大小
* @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; // 默認輸出圖片寬

private int outPutFileHeight = 100; // 默認輸出圖片高

private static boolean isScaleZoom = true; // 是否按比例縮放

public ZIPImage() {
outPutFilePath = "";
inPutFilePath = "";
inPutFileName = "";
autoBuildFileName = true;
outPutFileName = "";
}

/**
*
* @param ipfp
* 源文件夾路徑
* @param ipfn
* 源文件名
* @param opfp
* 目標文件路徑
* @param opfn
* 目標文件名
*/
public ZIPImage(String ipfp, String ipfn, String opfp, String opfn) {
outPutFilePath = opfp;
inPutFilePath = ipfp;
inPutFileName = ipfn;
autoBuildFileName = true;
outPutFileName = opfn;
}

/**
*
* @param ipfp
* 源文件夾路徑
* @param ipfn
* 源文件名
* @param opfp
* 目標文件路徑
* @param opfn
* 目標文件名
* @param aBFN
* 是否自動生成目標文件名
*/
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;
}

/**
* 壓縮圖片大小
*
* @return boolean
*/
public boolean compressImage() {
boolean flag = false;

try {
if (inPutFilePath.trim().equals("")) {
throw new NullPointerException("源文件夾路徑不存在。");
}
if (inPutFileName.trim().equals("")) {
throw new NullPointerException("圖片文件路徑不存在。");
}
if (outPutFilePath.trim().equals("")) {
throw new NullPointerException("目標文件夾路徑地址為空。");
} else {
if (!ZIPImage.mddir(outPutFilePath)) {
throw new FileNotFoundException(outPutFilePath
+ " 文件夾創建失敗！");
}
}

if (this.autoBuildFileName) { // 自動生成文件名
String tempFile[] = getFileNameAndExtName(inPutFileName);
outPutFileName = tempFile[0] + "_cyw." + tempFile[1];
compressPic();
} else {
if (outPutFileName.trim().equals("")) {
throw new NullPointerException("目標文件名為空。");
}
compressPic();
}

} catch (Exception e) {
flag = false;
e.printStackTrace();
return flag;
}

return flag;
}

// 圖片處理
private void compressPic() throws Exception {
try {
// 獲得源文件
file = new File(inPutFilePath + inPutFileName);
if (!file.exists()) {
throw new FileNotFoundException(inPutFilePath + inPutFileName
+ " 文件不存在！");
}
Image img = ImageIO.read(file);
// 判斷圖片格式是否正確
if (img.getWidth(null) == -1) {
throw new Exception("文件不可讀！");
} else {
int newWidth;
int newHeight;
// 判斷是否是等比縮放
if (ZIPImage.isScaleZoom == true) {
// 為等比縮放計算輸出的圖片寬度及高度
double rate1 = ((double) img.getWidth(null))
/ (double) outPutFileWidth + 0.1;
double rate2 = ((double) img.getHeight(null))
/ (double) outPutFileHeight + 0.1;

// 根據縮放比率大的進行縮放控制
double rate = rate1 > rate2 ? rate1 : rate2;

newWidth = (int) (((double) img.getWidth(null)) / rate);
newHeight = (int) (((double) img.getHeight(null)) / rate);

} else {
newWidth = outPutFileWidth; // 輸出的圖片寬度
newHeight = outPutFileHeight; // 輸出的圖片高度
}

BufferedImage tag = new BufferedImage((int) newWidth,
(int) newHeight, BufferedImage.TYPE_INT_RGB);

/*
* Image.SCALE_SMOOTH 的縮略演算法 生成縮略圖片的平滑度的 優先順序比速度高 生成的圖片質量比較好 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();
}
}

/**
* 創建文件夾目錄
*
* @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;
}

/**
* 獲得文件名和擴展名
*
* @param fullFileName
* @return
* @throws Exception
*/
private String[] getFileNameAndExtName(String fullFileName)
throws Exception {
String[] fileNames = new String[2];
if (fullFileName.indexOf(".") == -1) {
throw new Exception("源文件名不正確！");
} else {
fileNames[0] = fullFileName.substring(0, fullFileName
.lastIndexOf("."));
fileNames[1] = fullFileName
.substring(fullFileName.lastIndexOf(".") + 1);
}
return fileNames;
}

public Image getSourceImage() throws IOException{
//獲得源文件
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;
}

/*
* 獲得圖片大小
* @path ：圖片路徑
*/
public long getPicSize(String path) {
File file = new File(path);
return file.length();
}

}

//下面是測試程序

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\\","處理後的圖片.jpg",false);
zip.setOutPutFileWidth(1000);
zip.setOutPutFileHeight(1000);

Image image=zip.getSourceImage();
long size=zip.getPicSize("d:\\1.jpg");
System.out.println("處理前的圖片大小 width:"+image.getWidth(null));
System.out.println("處理前的圖片大小 height:"+image.getHeight(null));
System.out.println("處理前的圖片容量:"+ size +" bit");

zip.compressImage();
}
}