Java:使用 PDFBox 1 库从图像创建 PDF 页面
我需要将图像(主要是JPEG)直接转换为PDF文档的PDF页面。
可能是图像的大小不同。
每个 PDF 页面应具有与图像完全相同的尺寸。
因此,每个页面仅包含全分辨率的图像。
如何实现,将页面设置为图像/内容的尺寸?
因为我看到了具有不同页面大小和方向的PDF文件,但是如何使用PDFBox完成此操作?
我需要将图像(主要是JPEG)直接转换为PDF文档的PDF页面。
可能是图像的大小不同。
每个 PDF 页面应具有与图像完全相同的尺寸。
因此,每个页面仅包含全分辨率的图像。
如何实现,将页面设置为图像/内容的尺寸?
因为我看到了具有不同页面大小和方向的PDF文件,但是如何使用PDFBox完成此操作?
注意(Valentin Waeselynck的评论:从PDFBox 2 +开始,您现在将使用or or or 。请注意,这将大大降低空间效率。请参见: https://pdfbox.apache.org/2.0/migration.html#working-with-imagesPDImageXObject.createFromFile
PDImageXObject.createFromFile
JPEGFactory.createFromStream
LosslessFactory.createFromImage
PDFBox 1 的解决方案:
我用下面的代码解决了这个问题:
PDDocument document = new PDDocument();
InputStream in = new FileInputStream(someImage);
BufferedImage bimg = ImageIO.read(in);
float width = bimg.getWidth();
float height = bimg.getHeight();
PDPage page = new PDPage(new PDRectangle(width, height));
document.addPage(page);
PDXObjectImage img = new PDJpeg(document, new FileInputStream(someImage));
PDPageContentStream contentStream = new PDPageContentStream(document, page);
contentStream.drawImage(img, 0, 0);
contentStream.close();
in.close();
document.save("test.pdf");
document.close();
为了完整起见,PDFBox 2+ API 的当前 PDFBox 示例中的代码(https://svn.apache.org/repos/asf/pdfbox/trunk/examples/src/main/java/org/apache/pdfbox/examples/pdmodel/AddImageToPDF.java)
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.pdfbox.examples.pdmodel;
import java.io.File;
import java.io.IOException;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.PDPageContentStream;
import org.apache.pdfbox.pdmodel.PDPageContentStream.AppendMode;
import org.apache.pdfbox.pdmodel.graphics.image.PDImageXObject;
/**
* This is an example that creates a reads a document and adds an image to it..
*
* The example is taken from the pdf file format specification.
*
* @author Ben Litchfield
*/
public class AddImageToPDF
{
/**
* Add an image to an existing PDF document.
*
* @param inputFile The input PDF to add the image to.
* @param imagePath The filename of the image to put in the PDF.
* @param outputFile The file to write to the pdf to.
*
* @throws IOException If there is an error writing the data.
*/
public void createPDFFromImage( String inputFile, String imagePath, String outputFile )
throws IOException
{
try (PDDocument doc = PDDocument.load(new File(inputFile)))
{
//we will add the image to the first page.
PDPage page = doc.getPage(0);
// createFromFile is the easiest way with an image file
// if you already have the image in a BufferedImage,
// call LosslessFactory.createFromImage() instead
PDImageXObject pdImage = PDImageXObject.createFromFile(imagePath, doc);
try (PDPageContentStream contentStream = new PDPageContentStream(doc, page, AppendMode.APPEND, true, true))
{
// contentStream.drawImage(ximage, 20, 20 );
// better method inspired by http://stackoverflow.com/a/22318681/535646
// reduce this value if the image is too large
float scale = 1f;
contentStream.drawImage(pdImage, 20, 20, pdImage.getWidth() * scale, pdImage.getHeight() * scale);
}
doc.save(outputFile);
}
}
/**
* This will load a PDF document and add a single image on it.
* <br>
* see usage() for commandline
*
* @param args Command line arguments.
*/
public static void main(String[] args) throws IOException
{
AddImageToPDF app = new AddImageToPDF();
if( args.length != 3 )
{
app.usage();
}
else
{
app.createPDFFromImage( args[0], args[1], args[2] );
}
}
/**
* This will print out a message telling how to use this example.
*/
private void usage()
{
System.err.println( "usage: " + this.getClass().getName() + " <input-pdf> <image> <output-pdf>" );
}
}