java - 使用 Apache Batik 将 SVG 图像转换为 JPEG 图像

Question

我正在尝试将 SVG 图像转换为 JPEG，如 https://xmlgraphics.apache.org/batik/using/transcoder.html#createImage 中所示例子。这是代码:

public void saveAsjpeg() throws Exception {

    // Create a JPEG transcoder
    JPEGTranscoder t = new JPEGTranscoder();

    // Set the transcoding hints.
    t.addTranscodingHint(JPEGTranscoder.KEY_QUALITY, new Float(.8));

    // Create the transcoder input.
    String svgURI = new File(inputFilePath).toURL().toString();
    TranscoderInput input = new TranscoderInput(svgURI);

    // Create the transcoder output.
    OutputStream ostream = new FileOutputStream(outputFilePath);
    TranscoderOutput output = new TranscoderOutput(ostream);

    // Save the image.
    t.transcode(input, output);

    // Flush and close the stream.
    ostream.flush();
    ostream.close();
    System.exit(0);
}

下面是我的 pom.xml。我正在尝试 spring boot 项目:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.example</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>demo</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.3.4.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.xmlgraphics</groupId>
            <artifactId>batik-transcoder</artifactId>
            <version>1.8</version>
        </dependency>

        <dependency>
            <groupId>org.apache.xmlgraphics</groupId>
            <artifactId>batik-codec</artifactId>
            <version>1.8</version>
        </dependency>

        <dependency>
            <groupId>org.apache.xmlgraphics</groupId>
            <artifactId>batik-svgpp</artifactId>
            <version>1.8</version>
        </dependency>

        <dependency>
            <groupId>org.apache.xmlgraphics</groupId>
            <artifactId>batik-rasterizer</artifactId>
            <version>1.8</version>
        </dependency>

        <dependency>
            <groupId>org.apache.xmlgraphics</groupId>
            <artifactId>batik-squiggle</artifactId>
            <version>1.8</version>
        </dependency>

        <dependency>
            <groupId>org.apache.xmlgraphics</groupId>
            <artifactId>xmlgraphics-commons</artifactId>
            <version>2.1</version>
        </dependency>

        <dependency>
            <groupId>org.apache.xmlgraphics</groupId>
            <artifactId>batik-ttf2svg</artifactId>
            <version>1.8</version>
        </dependency>


    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-source-plugin</artifactId>
                <executions>
                    <execution>
                        <id>attach-sources</id>
                        <goals>
                            <goal>jar</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-javadoc-plugin</artifactId>
                <executions>
                    <execution>
                        <id>attach-javadocs</id>
                        <goals>
                            <goal>jar</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>


</project>

我遇到以下异常:

org.apache.batik.transcoder.TranscoderException: null
Enclosed Exception:
null
    at org.apache.batik.transcoder.image.ImageTranscoder.transcode(Unknown Source)
    at org.apache.batik.transcoder.XMLAbstractTranscoder.transcode(Unknown Source)
    at org.apache.batik.transcoder.SVGAbstractTranscoder.transcode(Unknown Source)
    at SaveToJPEG.saveAsjpeg(SaveToJPEG.java:31)
    at SaveToJPEG.main(SaveToJPEG.java:42)

我这里有几个问题:

1. 为什么异常堆栈跟踪显示“未知来源”并且异常没有提供信息？我用谷歌搜索并阅读到如果 jar 没有附加源代码，则异常可能没有信息。我已经将插件代码放在 pom 中以添加源代码。但这行不通。
2. batik 代码没有将 svg 图像转换为 jpeg 有什么问题？

Answer 1

我不知道是谁发布了这个 Artifact ，但它为我解决了这个问题

<dependency>
    <groupId>fr.avianey.apache-xmlgraphics</groupId>
    <artifactId>batik</artifactId>
    <version>1.8</version>
</dependency>

这些类包含在这个 Artifact 中

• org.apache.batik.ext.awt.image.codec.imageio.ImageIOPNGImageWriter
• org.apache.batik.ext.awt.image.codec.imageio.ImageIOTIFFImageWriter
• org.apache.batik.ext.awt.image.codec.imageio.ImageIOJPEGImageWriter