Java使用Spire.PDF实现高效压缩PDF文件

// 创建 PdfCompressor 对象并传入文档
PdfCompressor compressor = new PdfCompressor("test.pdf");

// 压缩内容
OptimizationOptions options = compressor.getOptions();
options.setCompressContents(true);

// 压缩图片
options.getImageCompressionOptions().setCompressImage(true);
options.getImageCompressionOptions().setImageQuality(ImageQuality.Low);
options.getImageCompressionOptions().setResizeImages(true);

// 优化字体
options.getTextCompressionOptions().setCompressFonts(true);

<repositories>
    <repository>
        <id>com.e-iceblue</id>
        <name>e-iceblue</name>
        <url>https://repo.e-iceblue.com/nexus/content/groups/public/</url>
    </repository>
</repositories>

<dependency>
    <groupId>e-iceblue</groupId>
    <artifactId>spire.pdf</artifactId>
    <version>11.8.3</version>
</dependency>

<dependency>
    <groupId>e-iceblue</groupId>
    <artifactId>spire.pdf.free</artifactId>
    <version>9.13.0</version>
</dependency>

<dependency>
    <groupId>com.luhuiguo</groupId>
    <artifactId><a href="https://zhida.zhihu.com/search?content_id=252656435&content_type=Article&match_order=1&q=aspose-pdf&zhida_source=entity" target="_blank" rel="nofollow">aspose-pdf</a></artifactId>
    <version>23.1</version>
</dependency>

public class OptimizePdf {

    public static void optimize(String source, String target) {
        <a href="https://zhida.zhihu.com/search?content_id=252656435&content_type=Article&match_order=1&q=Document&zhida_source=entity" target="_blank" rel="nofollow">Document</a> doc = new Document(source);
        //设置压缩属性
        <a href="https://zhida.zhihu.com/search?content_id=252656435&content_type=Article&match_order=1&q=OptimizationOptions&zhida_source=entity" target="_blank" rel="nofollow">OptimizationOptions</a> opt = new OptimizationOptions();
        //删除PDF不必要的对象
        opt.setRemoveUnusedObjects(true);
        //链接重复流
        opt.setLinkDuplcateStreams(false);
        //删除未使用的流
        opt.setRemoveUnusedStreams(false);
        //删除不必要的字体
        opt.setUnembedFonts(true);
        //压缩PDF中的图片
        opt.getImageCompressionOptions().setCompressImages(true);
        //图片压缩比， 0 到100可选，越低压缩比越大
        opt.getImageCompressionOptions().setImageQuality(50);
        doc.optimizeResources(opt);
        //优化web的PDF文档
        doc.optimize();
        doc.save(target);
    }

    public static void main(String[] args) {
        String source = "/Users/zhanghe/Desktop/2.pdf";
        String target = "/Users/zhanghe/Desktop/1.pdf";
        optimize(source, target);
    }
}

<dependency>
            <groupId>org.apache.pdfbox</groupId>
            <artifactId>pdfbox</artifactId>
            <version>3.0.0</version>
        </dependency>

import org.apache.pdfbox.Loader;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.PDResources;
import org.apache.pdfbox.pdmodel.graphics.image.JPEGFactory;
import org.apache.pdfbox.pdmodel.graphics.image.PDImageXObject;
import org.apache.pdfbox.cos.COSName;

import java.io.File;
import java.io.IOException;

public class TextOptimizedPdfCompressor {

    public static void textOptimizedPdfCompressor(String inputPath, String outputPath) {
        try (PDDocument document = Loader.loadPDF(new File(inputPath))) {
            // 核心优化流程（传递 document 参数）
            for (PDPage page : document.getPages()) {
                compressContent(page);
                compressImages(document, page); // ✅ 关键修改：传入 document 对象
            }

            document.save(outputPath);
            System.out.println("✅ 压缩完成！");
        } catch (IOException e) {
            System.err.println("错误信息: " + e.getMessage());
        }
    }

    // ================= 内容流压缩 =================
    private static void compressContent(PDPage page) {
        page.getCOSObject().setItem(COSName.FILTER, COSName.FLATE_DECODE);
        page.getCOSObject().setInt(COSName.BITS_PER_COMPONENT, 8);
    }

    // ================= 图片压缩模块 =================
    private static void compressImages(PDDocument document, PDPage page) throws IOException {
        PDResources resources = page.getResources();
        if (resources == null) return;

        for (COSName name : resources.getXObjectNames()) {
            if (resources.isImageXObject(name)) {
                PDImageXObject image = (PDImageXObject) resources.getXObject(name);

                // 仅处理大尺寸图片
                if (image.getWidth() * image.getHeight() > 1_000_000) {
                    // ✅ 正确方式：使用传入的 document 参数
                    PDImageXObject compressedImg = JPEGFactory.createFromImage(
                            document,
                            image.getImage(),
                            0.1f
                    );
                    resources.put(name, compressedImg);
                }
            }
        }
    }
}