使用JPedal取得PDFBox

      之前都是使用PDFBOX0.8版本来实现PDF转为Image，0.8版本的PDFBox转为Image还有N多问题，比如部分扫描PDF无法转换、缺少字体等等问题。而且我们是修改PDFBox源代码来解决上述问题，但是还是不能解决全部问题。

     JPedal是一个商业的处理PDF软件，但是JPedal有一个裁切版，裁切版JPedal使用LGPL协议进行开源，可免费使用。如下摘抄官方说明：

JPedal is a commercial PDF library, so it is not free (and it cannot realistically be because no income means no money to fund development and support). OEM customers also get access to the source code so they have free access to the product in the sense they are not limited – they can alter it if they want. Commercial users get free support in the sense we charge everyone a yearly fee to cover general support costs.

We also have a cutdown version of the PDF viewer which we release under an LGPL license. This means that you can access the source code and the jar and use them without any payment. You just have to abide by the LGPL license. In this sense it is totally free.

We build it from the full version and remove items (so it gets most bug fixes and some features). So it is free in that sense. Our hope is that it will encourage lots of people to use it, to do interesting things with it and some may become commercial clients. And we like to have a free entry-level version – it appeals to the rebel in our nature  

And being a cut-down version of a commercial product means you are likely to see updates – there are several ‘dead’ free Java PDF libraries because they do not generate any revenues to put back into development and support.

 

   选择使用JPedal替换Pdfbox出于如下方面考虑：

    第一：解决扫描类PDF、缺少字体问题，不用修改源代码，解决软件后续维护升级问题。

    第二：转换效率高。一个70页PDF，使用PDFBox转换时间为27秒左右，而且使用JPedal的转换时间才16秒，大大地缩短转换时间。

    第三：由于只需要把PDFBox转换为Image，暂无其他需求，故裁切版JPedal已可满足需求。

 

   下面使用JPedal 转换为图片的代码：

                                                               /** instance of PdfDecoder to convert PDF into image */
		                              PdfDecoder decode_pdf = new PdfDecoder(true);

		                                 /** set mappings for non-embedded fonts to use */
		                                PdfDecoder.setFontReplacements(decode_pdf);


				/** open the PDF file - can also be a URL or a byte array */

				decode_pdf.openPdfFileFromInputStream(in, false);
				// decode_pdf.openPdfFile("C:/myPDF.pdf", "password"); //encrypted
				// file
				// decode_pdf.openPdfArray(bytes); //bytes is byte[] array with PDF
				// decode_pdf.openPdfFileFromURL("http://www.mysite.com/myPDF.pdf",false);

				/** get page 1 as an image */
				// page range if you want to extract all pages with a loop
				// int start = 1, end = decode_pdf.getPageCount();
				int pageCount = decode_pdf.getPageCount();
				

				if (curPage > pageCount || curPage <= 0)
					curPage = pageCount;

				BufferedImage img = null;

				img = decode_pdf.getPageAsImage(curPage );
				
				pageCnt=String.valueOf(pageCount);
				
				FileOutputStream out;
				out = new FileOutputStream(file);

				JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
				encoder.encode(img);
				out.close();

 

 

我以前也做过PDF转图片的项目，当时有两件事很头疼：
1）无法解析内嵌字体
2）无法解析加密文档（ adobe可以打开）
不知道楼主是否遇到这些问题？

测试一千多份pdf文件，到目前为止未发现无法解析内嵌字体的问题，不知道你说那些内嵌字体？

jpedal pdf转图片  ，，能调图片的清晰度吗，，我发现转完不够清晰。