We are pleased to announce the release of PDFTron SDK 6.10 . This release features a number of improvements, including support for generating document comparisons. If you would like to try it out, check our guides for either Windows or Linux to get started.

Built-in Visual Comparison

PDFTron SDK can now generate a visual comparison between two different documents. The comparison result itself is a resolution independent PDF -- well suited for adding high-quality diff support into existing app workflows.

Large File Support for 32 bit builds

While the PDFTron SDK has supported files of any size on 64 bit systems (system resources allowing), this is now possible on 32 bit systems as well when constructing PDFDoc objects using a file path. For the majority of operations (like rendering or text extraction) working with very large documents is practical even in resource constrained environments.

Improved XFDF support for Measurement and Redaction

We've added new capability to our xfdf routines, improving PDFTron SDK's interaction with PDFTron WebViewer. In particular, we can now import and export measurement annotations, redaction annotations, and form tooltips generated by WebViewer.

Improved Windows font substitution

Our font substitution routines have been improved on Windows systems. In cases where the text to be displayed is in more than one language or has occasional unusual characters, our font choices will be more a appropriate (and with fewer missing glyphs). The changes are aimed towards better handling of user-created text, such as annotations.

Improved Office conversion quality

Some improvements to our office conversion quality in the release include:

  • Support automatic image color transformations.
  • Support for automatic removal of background colors from images in Office files.
  • Better chart support, in particular, doughnut charts and chart labels in general.
  • Improved line breaking with specific types of hyphens.
  • Tweaked layout of in-line images to better match MS Office.
  • Now support vertical padding in floating objects (images/shapes/textboxes)
  • Added support for tiled background images in Excel documents.
  • Improved handling of missing fonts, or incorrectly specified fonts.
  • Better handling of Excel cells with missing styles.
  • Many more.


As always, the latest release includes a number of situational performance improvements as well:

  • Better handling of nested clipping groups when rendering. A modest improvement in memory usage in all cases, and drastic improvements (more than 30x is possible) to memory usage and performance when clipping paths are deeply nested.
  • More efficient handling of documents with many Null SDF objects, especially those in compressed object streams.
  • Improved memory usage when converting extremely large Excel sheets.
  • Many smaller incremental improvements.