BFO Blog - Java PDF Software tips and tricks. - PDF Library category

Extending the PDF Viewer - Part 1

Mon, 21 Dec 2009 13:55:54 GMT

The BFO PDF Viewer has a simple framework and API for adding new features. This article will show how to add a simple widget to the toolbar and then add more features that interact with the PDF document itself.

Public Key Encryption and PDF

Thu, 12 Nov 2009 14:10:22 GMT

Most people when they think of protecting a PDF, think of a password. However this isn't the only way to do it. Both Acrobat and our PDF viewer allow a PDF to be decrypted using a private key which is specific to a user. In this article we show you how to create a key, encrypt a document for that key and then decrypt it again.

QR-Code and other barcodes

Wed, 07 Oct 2009 15:00:09 GMT

The PDF Library supports a large number of barcodes, including QR-Code. This article shows some tricks you can do with these dense 2D barcodes.

Silently* print a PDF from a web browser

Mon, 28 Sep 2009 14:46:00 GMT

We occasionally are asked how to print a PDF from a web browser without displaying a dialog. There isn't an easy answer to this, but you can get fairly close with our Viewer API.

Logging with BFO

Tue, 07 Jul 2009 15:38:31 GMT

The release of 2.11.6 of the BFO PDF library sees the introduction of a consolidated logging API that can be integrated into customer's existing logging systems. Read on to find out how to configure BFO products to log with Log4J or java.util.logging.

JPEG2000, Java and PDF

Wed, 27 May 2009 13:32:00 GMT

The JPEG 2000 compression algorithm was designed in 2000 as a successor to the venerable JPEG algorithm, which dates back to 1992. It's designed to compress "continuous tone" images such as photographs, and supports both a lossy (like JPEG) and a lossless format. We covered a bit on image compression in in a previous article.

Adobe added support for JPEG 2000 compressed images in Acrobat 5.0, (calling it JPX compression), and it's becoming more and more common to find PDF Documents containing photographic images compressed with this algorithm.

Creating PDF/A documents with the BFO library

Fri, 20 Feb 2009 10:21:00 GMT

PDF/A is a standardised subset of PDF used for long-term archive storage. The PDF/A format ensures that documents can be correctly rendered hundreds of years from now in the absence of standard frameworks we take for granted today. Read more to find out how to author PDF/A documents with the BFO PDF library.

Gotchas when reading and writing PDF to files

Mon, 26 Jan 2009 16:49:12 GMT

Reading and writing PDF documents to and from the same disk file can have unexpected consequences. This article covers what to watch out for if you do this, and details a few ways to get around the problems it can cause, including the new features added in 2.11.2 for this problem.

BFO releases Java PDF library 2.11.2

Thu, 22 Jan 2009 17:57:00 GMT

BFO have released a new version of their Java PDF Library.

Version 2.11.2 fixes an issue with IBM versions of Java that was introduced in the previous release - a change of obfuscator clashed with a bug in some releases of the JRE supplied with Websphere. There are fixes for Customers reading and writing PDFs to the same File, a memory leak in the Viewer has been fixed, and a number of bugs have been fixed, including a Swing screen corruption issue that sometimes occurred on Windows.

The full changelog is available here, and the new release is available to download at http://bfo.co.uk/products/download.jsp

New features for Java applets

Mon, 05 Jan 2009 10:39:00 GMT

Sun have rewritten the Java browser plugin in Java 6 Update 10 to address many of the issues that people have experienced with deploying Java applets, and to add new features such as dragging applets out of the browser. We have updated the PDF Viewer Applet to take advantage of these features, and we'll show how you can update your own deployment of the PDF Viewer Applet, or any other applet, to do the same.

Big Faceless releases Java PDF Library 2.10.4

Tue, 14 Oct 2008 00:13:00 GMT

BFO are pleased to announce the 2.10.4 release of their PDF library. Several months in the making, it contains a large number of changes, mostly under the hood.

For the end user, the primary new features will be the new single column display in the Viewer; improvements to allow the library to work with XFA-only PDFs and the addition of the new USPS "IntelligentMail" BarCode. There was also a large rewrite of the font-subsystem, improving the ability of the library to render unusually constructed PDFs and paving the way for future enhancements. The full list of changes is in the PDF Library Changelog

As always, the latest release is at avilable for download at the BFO website

Converting PDF to TIFF, PNG and JPEG

Thu, 31 Jul 2008 15:20:47 GMT

We're asked some questions more than others at BFO, and one of the most common concerns conversion of a PDF to a bitmap image format - typically TIFF, but sometimes JPEG or another format. This process is called "rasterization" and while it's very easy to do with the "extended plus viewer" version of our PDF Library, it's worth going over in more detail.

Linearized PDF

Thu, 17 Jul 2008 14:52:51 GMT

The 2.10.3 release of the PDF library adds support for writing "Linearized" PDF documents, sometimes called "Web Optimized" or "Fast Web View" enabled. This feature has been a part of the PDF specification since Acrobat 3.0, but it's poorly understood even by developers.

The idea behind linearization is faster display of PDF documents downloaded from the web. It does this by arranging the document structure in a specific way, and adding "hints tables" which specify the position in the file of certain objects.