FO 到 PDF/a 使用 Apache FOP Java 库的转换

Question

我正在尝试使用文档中给出的 exemple 代码将 .fo 文件转换为 PDF/a 和 Apache FOP 2.1。我设法将 helloworld.fo 文件转换为 PDF，但是，当我尝试将其转换为 PDF/a 文件时，出现此错误：

org.apache.fop.pdf.PDFConformanceException: For PDF/A-1a, all fonts, even the base 14 fonts, have to be embedded! Offending font: /Helvetica

这就是我尝试在 fop.xconf 文件中嵌入字体的原因： <pre><code> <fonts> <font-triplet name="Arial" style="normal" weight="700"/> <font-triplet name="Arial" style="normal" weight="bold"/> <font-triplet name="Arial" style="italic" weight="700"/> <font-triplet name="Arial" style="italic" weight="bold"/> <directory>C:\Users\thinkpad\workspace\FopConverter\Fonts</directory> <directory>C:\Users\thinkpad\workspace\FopConverter\Fonts\ghostFonts</directory> <substitutions> <substitution> <from font-family="Helvetica" font-weight="700..900"/> <to font-family="Arial"/> </substitution> </substitutions> <auto-detect/> </fonts>

但即使这样做我仍然有同样的错误：org.apache.fop.pdf.PDFConformanceException: For PDF/A-1a, all fonts, even the base 14 fonts, have to be embedded! Offending font: /Helvetica

我还尝试通过在 <fo:root"> 中添加 font-family="Helvetica" font-weight="normal" font-style="normal" 来修改 helloworld.fo，因为一些 forum topic 说这样做但它没有改变任何东西。

请帮助我解决嵌入字体错误。感谢阅读本主题。

[编辑]：这是完整的错误消息：

FOP ExampleFO2PDF

Preparing...
Input: XSL-FO (.\xml\fo\helloworld.fo)
Output: PDF (.\out\ResultFO2PDF.pdf)

Transforming...
août 07, 2017 11:26:49 AM org.apache.fop.events.LoggingEventListener processEvent
INFOS: Rendered page #1.
org.apache.fop.pdf.PDFConformanceException: For PDF/A-1b, all fonts, even the base 14 fonts, have to be embedded! Offending font: /Helvetica
    at org.apache.fop.pdf.PDFFont.validate(PDFFont.java:170)
    at org.apache.fop.pdf.PDFFont.output(PDFFont.java:179)
    at org.apache.fop.pdf.PDFDocument.outputIndirectObject(PDFDocument.java:1053)
    at org.apache.fop.pdf.PDFDocument.streamIndirectObject(PDFDocument.java:1018)
    at org.apache.fop.pdf.PDFDocument.output(PDFDocument.java:994)
    at org.apache.fop.pdf.PDFDocument.outputTrailer(PDFDocument.java:1097)
    at org.apache.fop.render.pdf.PDFDocumentHandler.endDocument(PDFDocumentHandler.java:191)
    at org.apache.fop.render.intermediate.util.IFDocumentHandlerProxy.endDocument(IFDocumentHandlerProxy.java:187)
    at org.apache.fop.render.intermediate.IFRenderer.stopRenderer(IFRenderer.java:295)
    at org.apache.fop.area.RenderPagesModel.endDocument(RenderPagesModel.java:265)
    at org.apache.fop.area.AreaTreeHandler.endDocument(AreaTreeHandler.java:342)
    at org.apache.fop.fo.FOTreeBuilder.endDocument(FOTreeBuilder.java:170)
    at org.apache.xalan.transformer.TransformerIdentityImpl.endDocument(TransformerIdentityImpl.java:963)
    at org.apache.xerces.parsers.AbstractSAXParser.endDocument(Unknown Source)
    at org.apache.xerces.impl.XMLDocumentScannerImpl.endEntity(Unknown Source)
    at org.apache.xerces.impl.XMLEntityManager.endEntity(Unknown Source)
    at org.apache.xerces.impl.XMLEntityScanner.load(Unknown Source)
    at org.apache.xerces.impl.XMLEntityScanner.skipSpaces(Unknown Source)
    at org.apache.xerces.impl.XMLDocumentScannerImpl$TrailingMiscDispatcher.dispatch(Unknown Source)
    at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
    at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
    at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
    at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
    at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source)
    at org.apache.xalan.transformer.TransformerIdentityImpl.transform(TransformerIdentityImpl.java:485)
    at ConverterFO2PDFa.convertFO2PDF(ConverterFO2PDFa.java:104)
    at ConverterFO2PDFa.main(ConverterFO2PDFa.java:154)

Answer 1

经过一些更改后，我能够使用相同的示例文件创建 PDF/A 输出：

在 输入 FO 文件 中，我在影响所有文本的位置明确添加了 font-family="Helvetica"（或您最喜欢的字体系列）

如果没有这个，即使 FOP 在没有设置 font-family 时默认使用 Helvetica，它显然也无法找到它的配置。

在配置文件中，我将 Helvetica 字体系列映射到现有字体，例如 Arial

<font kerning="yes" embed-url="/Library/Fonts/arial.ttf">
  <font-triplet name="Helvetica" style="normal" weight="normal"/>
</font>

在 Java 代码 中，我将 FOP 配置为使用我的配置文件，并将用户代理配置为启用辅助功能

import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.DefaultConfigurationBuilder;
import org.apache.fop.apps.FopFactoryBuilder;

...
DefaultConfigurationBuilder cfgBuilder = new DefaultConfigurationBuilder();
Configuration cfg = cfgBuilder.buildFromFile(new File("/Users/lfurini/fop.xconf"));
FopFactoryBuilder fopFactoryBuilder = new FopFactoryBuilder(new File(".").toURI()).setConfiguration(cfg);
FopFactory fopFactory = fopFactoryBuilder.build();

FOUserAgent foUserAgent = fopFactory.newFOUserAgent();
// configure foUserAgent as desired
foUserAgent.setAccessibility(true);
foUserAgent.getRendererOptions().put("pdf-a-mode", "PDF/A-1b");
...

FO 到 PDF/a 使用 Apache FOP Java 库的转换

FO to PDF/a Conversion with Apache FOP Java Library

java

fonts

apache-fop

pdfa