Java操作Google Webp图片格式转换实践- JAVA

webp压缩的好处

Java使用webp代码编译

Webp开源项目

nintha/webp-imageio-core

webp压缩的好处

可以缩小网络传输和磁盘占用空间。

Java使用webp代码编译

webp-imageio
开源库下载压缩包到本地进行编译jar，工程用gradle来维护。
libwebp
google-developer下载压缩包到本地编译动态链接库-不同平台的动态链接库编译出来是不同的。mac下是.dylib, windowns下是.dll, unix/linux下是.so. 我在mac和linux下编译过，记录下linux下编译过程。
compiling


libwebp-0.6.1.tar.gz luciad-webp-imageio-8f9b44b41902.zip
 
tar -xzvf libwebp-0.6.1.tar.gz
unzip luciad-webp-imageio-8f9b44b41902.zip
mv libwebp-0.6.1 ./luciad-webp-imageio-8f9b44b41902/libwebp


cd luciad-webp-imageio-8f9b44b41902
cmake .
cmake --build .

cmake如果装的话，请自行下载安装官网安装用法

./gradlew build -x test

java project
将libwebp-imageio.so放入工程的当前目录，因为默认的java.library.path含工程当前路径。同时引入打好的luciad-webp-imageio-8f9b44b41902-0.6.0-SNAPSHOT.jar引入工程中。如果是maven工程的话，可以把jar先推到远程的仓库里。

java transfer


image = ImageIO.read(new URL(imageUrl));
// Encode it as webp using default settings
boolean result = ImageIO.write(image, "webp", bos);

gradle push to repositry
update build.gradle


apply plugin: "maven-publish" //插件required
group = "com.luciad.imageio.webp"
 
publishing {
    publications {
        mavenJava(MavenPublication) {
           from components.java
        }
    }
    repositories {
        maven {
             url "http://***"
             credentials {
                      username = ****
                      password = ****
            }
      }
   }
}

publish

gradle publishMavenPublicationToMavenRepository

有时间的话可以自己编译，此处来自：https://www.jianshu.com/p/5827f9063fe9

Webp开源项目

nintha/webp-imageio-core

qwong/j-webp

可用的webp依赖和包

下载此开源项目没有跑起来，dll包有问题。直接使用0.4.2可以正常使用，下载地址如下：

http://download.csdn.net/download/geeklei/8163329
https://download.csdn.net/download/geeklei/8161731
链接：https://pan.baidu.com/s/1JZB_cNNr3Pf8sv2hdvu_-A
提取码：zvql
复制这段内容后打开百度网盘手机App，操作更方便哦

Webp 编解码

编码


package example;
 
import com.luciad.imageio.webp.WebPWriteParam;
 
import javax.imageio.IIOImage;
import javax.imageio.ImageIO;
import javax.imageio.ImageWriter;
import javax.imageio.stream.FileImageOutputStream;
 
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
 
public class EncodeTest {
    public static void main(String args[]) throws IOException {
        String inputPngPath = "test_pic/test.png";
        String inputJpgPath = "test_pic/test.jpg";
        String outputWebpPath = "test_pic/test_.webp";
 
        // Obtain an image to encode from somewhere
        BufferedImage image = ImageIO.read(new File(inputJpgPath));
 
        // Obtain a WebP ImageWriter instance
        ImageWriter writer = ImageIO.getImageWritersByMIMEType("image/webp").next();
 
        // Configure encoding parameters
        WebPWriteParam writeParam = new WebPWriteParam(writer.getLocale());
        writeParam.setCompressionMode(WebPWriteParam.MODE_DEFAULT);
 
        // Configure the output on the ImageWriter
        writer.setOutput(new FileImageOutputStream(new File(outputWebpPath)));
 
        // Encode
        long st = System.currentTimeMillis();
        writer.write(null, new IIOImage(image, null, null), writeParam);
        System.out.println("cost: " + (System.currentTimeMillis() - st));
    }
}

解码


package example;
 
import com.luciad.imageio.webp.WebPReadParam;
 
import javax.imageio.ImageIO;
import javax.imageio.ImageReader;
import javax.imageio.stream.FileImageInputStream;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
 
public class DecodeTest {
    public static void main(String args[]) throws IOException {
    	System.load("C:\\Users\\admin\\Desktop\\webp\\webp-code\\webp-imageio-core\\src\\main\\resources\\META-INF\\lib\\windows_64\\webp-imageio.dll");
        String inputWebpPath = "test_pic/test.webp";
        String outputJpgPath = "test_pic/test_.jpg";
        String outputJpegPath = "test_pic/test_.jpeg";
        String outputPngPath = "test_pic/test_.png";
 
        // Obtain a WebP ImageReader instance
        ImageReader reader = ImageIO.getImageReadersByMIMEType("image/webp").next();
 
        // Configure decoding parameters
        WebPReadParam readParam = new WebPReadParam();
        readParam.setBypassFiltering(true);
 
        // Configure the input on the ImageReader
        reader.setInput(new FileImageInputStream(new File(inputWebpPath)));
 
        // Decode the image
        BufferedImage image = reader.read(0, readParam);
 
        ImageIO.write(image, "png", new File(outputPngPath));
        ImageIO.write(image, "jpg", new File(outputJpgPath));
        ImageIO.write(image, "jpeg", new File(outputJpegPath));
 
    }
}