Monthly Archives: July 2014

Secure PDF Printing

One of the security features many PDF publishers want to see is control over printing of their PDFs. This turns out to be rather more complicated than it might seem at first. Essentially there are two main options: (i) do not allow printing of any kind; and (ii) allow printing subject to some restrictions. The first option is the most common situation, and applies to many different types of document, especially ebooks. It is relatively easy to handle by not providing print facilities in the reader software or by disabling such facilities if they exist. In the case of standard (Adobe-style) PDFs this can be defined via the Security settings options in Adobe Acrobat. But remember that non-Adobe PDF readers may not respect these settings (i.e. ignore them with the result that the file is not actually secured at all) or may be subject to breach if the security settings are attacked using widely available software.

The second option has many variants, and these have become more complicated in the last 2-3 years. This is due to the rise of printers that are indirectly linked to the PC or Mac or other device, so may or may not appear to be real, physical devices… often they appear as WiFi “air” printers or in-network print server software packages. In general PDF publishers who permit printing wish to limit some aspects of this facility, such as:

(i) never allow printing to PDF or Image virtual printers
(ii) only print to local devices
(iii) only permit printing a certain number of times
(iv) only permit printing of a certain number of pages
(v) include an intelligent (user/computer/date/file-specific) watermark on some or all pages

This functionality has been supported as standard in  Javelin PDF readers for a long time, but the rise of the printer-that-is-not-obviously-a-printer has led to problems, especially with requirement (i). Within Drumlin v6 and the matching Javelin releases, this issue is handled by selecting the “Relaxed printing” flag in the Permissions form when creating a secure PDF. This flag uses a less strict algorithm than is the standard ‘strict’ version, with the result that the newer devices should be accepted as valid printers. If a warning message “Error -30” is issued it means that currently the Javelin reader being used cannot recognize the print device as valid – email us with full details (printer/print software Make, Model, version etc) and we will ensure it is included in our “Relaxed printing” facility.

Google Nexus – a suitable device for reading PDFs and eBooks?

The release of the Google (Asus) Nexus 7 in late 2012 launched a very impressive 7 inch tablet device running Android onto an eager marketplace. The question we asked at the time is “can Android tablet devices replace Kindles, Nooks and iPADs in the ever changing world of ebook readers?”. We said we thought so, at least from a technical point of view, and assuming a really good PDF viewer is available (see further, below). Here is our review at time – the evidence since then seems to support these views, with similar products being launched by other providers such as Samsung, and new size versions from Google (5inch, 10inch and a rumored 9inch forthcoming).

The image below, from the Google Nexus website (see link below) provides a first look at this question – in this case illustrating a conventional ePUB ebook. The Kindle reader for Android looks much the same, although when rotated seems to insist on showing two columns rather than one, which is not ideal for reading.

In principle this looks fine – firstly, it has a really good hi-res screen (1280×800 pixels, or 216dpi (2012 version – latest versions are an extraordinary 323dpi), which is far far better than typical computer screens  – most have less than 100dpi). Second, the screen auto-rotates so text can be displayed much more clearly if an entire page width is used as the zoom setting (“fit width” in PDF parlance). However, to do this you first have to enable auto-rotation, as Google for some reason have it disabled when you first get the device. Also, the term 7 inch is a bit misleading – the available diagonal screen size when reading a document is roughly 6.5inches, and in landscape view this equates to just over 5.5 inches (15cms) or only 3.5inches (9.5cms) in the standard portrait view.

The image above shows re-flowable text, whereas PDFs provide formatting and fixed layouts. If the layout includes margins, which is generally the case with PDF documents, then this white space limits the available width, as shown in the test image below:

Of course, this image is actually larger than the physical screen, but the results are nonetheless very readable (the resolution difference between the PC and the Nexus accounts for this).

Markup and annotation are features that some users require, and the image below shows this in an implementation which will be similar to the one used by our Javelin reader for Android:

Adobe and Drumlin PDF Watermarking – static and dynamic watermarks

PDF files can be protected from unauthorized copying in multiple ways. One of these is by the inclusion of watermarking, which itself comes in many variants.

Static watermarks

The first is the pre-loaded static watermark. If watermarks are added statically they are generally created by using a tool such as Adobe Acrobat or Infix to create an additional foreground or background item on some or all pages of a PDF. The screenshot below illustrates this, and as can be seen, the text entered appears on the selected page – here as a simple text string, in the color, size and orientation selected. Adobe Acrobat is very flexible in providing options for statically added watermarks of this type. Once added the PDF must be saved, so that the additional content form a permanent part of the PDF file itself. If this file is then protected, using Adobe’s standard security facilities, preferably with a longish password (8+ alpha-numerics) then the watermarking will have a reasonable level of protection against removal. Note that the watermark can contain any statically defined information you wish, so can be generic, e.g. “(c) My Company, 2013”, or “!This file has been issued to Mr A B Johnson of XYZ Inc – no copying of this file is permitted”

Dynamic watermarks

The second approach is the use of dynamic watermarking. As with static watermarking a dynamic watermark can contain static text, such as “(c) My Company 2013”, but that misses the real value of such facilities. The main feature of a dynamic watermark is that it includes information generated at the moment of display or printing, which includes end user or other information that makes the file “unique” and identifiable.

In the example below there are both static and dynamic watermarks included. The static watermark has been added to the source document using Adobe Acrobat – in this case it has been placed at a diagonal across the text in such as way as to extend across the page but with minimal interference with the text. The dynamic watermark, created using Drumlin, is shown at the foot of the page, and includes information about the file displayed (the filename itself), plus information that identifies the user (via the partially displayed code), the device on which the document is displayed, the date and other information. This  information is dynamically generated when the file is displayed and is overlaid onto this viewable screen window rather than embedded in the document. This means that when the page is zoomed in or out, the dynamic watermark is always displayed in front of the viewable area. This provides an added level of protection for the document against screen capture that is now a standard feature of many operating systems and hardware devices (e.g. a built in feature of Android and iPAD mobile devices). There are also a range of server-driven tools and PDF security products (e.g. those from Adobe, Vitrium, Foxit and others) that will automatically stamp or watermark PDF files that are downloaded.

Javelin PDF Reader V2 release

Javelin PDF for Windows has just had a major upgrade – it is often the first of our PDF readers that publishers experiment with, so we have been working hard to provide a whole series of functional enhancements that customers have requested. The updates improve the functionality whilst retaining the speed of the reader and its tiny size. Further developments are planned for this year..

Please download and try the new version of Javelin for Windows – you can install this new version over the existing version you have – it will not affect your existing saved data or file authorizations. A User Guide in PDF format can be downloaded from the Documentation page of our website and is included in the new kit.

Changes for the new release (Javelin for Windows V2) include:

  • Annotation: probably the most frequently requested functional enhancement, this new release provides a simple annotation facility for pdf, drmz and drmx files (not exe files). Annotations are stored separately, in the same directory as the drmx/drmz file they apply to (the directory must be available for writing to, e.g. the Documents folder for the current user. A new tab section is provided in addition to the document outline/navigation tree tab which shows the note headings throughout the document (see screenshot below). These can be clicked to move the relevant page with the note displayed. Notes are added via right click with the mouse, clicking on the toolbar icon or via the Tools menu.

  • Enhanced zoom facilities: these include a drop-down zoom-level selection box, plus a new feature, marquee zoom (see screenshot, above). The latter feature enables you to select and area of the screen and zoom straight to that region. The special Marquee zoom icon is shown to the right of the drop-down zoom selector box. The Hand icon enables you to return to non-zoomed mode where you can drag the page around. A ‘ping’ is sounded if the zoom level exceeds a certain level. These features are similar to those provided within Adobe’s latest reader software
  • Extended support for Chinese, Korean, Japanese and other non-latin based systems. This enables certain regional variants of Windows to authorize secure PDF files without needing to switch to an English-language regional variant temporarily.
  • Support for extended character sets in navigation trees (outline/bookmark trees): navigation trees are of major value in electronic versions of ebooks and other documents. However, there are many variants of how these are implemented, and in some instances accented and other characters embedded in these trees mean that they do not link to pages as expected. With the latest updates such special and accented characters will now be processed and links established
  • Built-in file downloader: a new facility is available on the tools menu and toolbar (see above) to enable a file to be downloaded directly to Javelin and opened – currently .pdf, .drmz and .drmx files are supported
  • Properties option on the File menu, providing file properties for both PDF and DRM files.
  • Un-authorize option, with centralized logging: this is to enable an end user to demonstrate that they have removed access to a file from their system, even after initially authorizing it.
  • Activity log: Enhanced activity log information (available for viewing via the AdminApp) to identify the exact Microsoft Windows OS version and deviceID in use (all other OS variants are alresdy logged in this way)
  • Intelligent watermarking: Amendment of the %I field in the intelligent watermarking facility to specifiy the ID of the computer being used.
  • Extra security features: additional security features have been built into Javelin for Windows (more details available on request!).
  • Minor tweaks  – cosmetic and other minor changes
  • Windows tablet devices: the new MS Windows “Surface” tablets running Windows 8.1, for example, can be used with the latest versions of Javelin. The built-in keyboard and mouse or attached devices for keyboard and mouse operation should be used (not full touch screen support at present).

How to edit your PDFs – we review the Infix PDF editor

I recently stumbled across the Infix PDF editor, from Iceni Technology (pronounced eye-seen-ee apparently, an ancient tribe from East Anglia), Anyway, it is a great piece of software for editing and augmenting PDFs, at a very good price (much cheaper than Adobe Acrobat, and with more powerful editing functionality). Essentially Infix is a wysiwyg editor for PDFs. It understands the mysterious and convoluted structure of PDFs and their many variants, so you can directly edit on-screen, very much as you would in Word or InDesign. The big difference is that you can amend the PDF output without necessarily having the source file from which it was created. You can even do really tricky things like trying to re-create the source file, or translate the PDF into other languages. Furthermore, you can augment existing PDFs with features like Adobe-style security, navigation trees, hyperlinks, annotations and more.

The screenshot below provides a glimpse of the functionality, where we have selected a text box to amend and added redaction to a section of text. A VERY brief summary of some of the key features that we like include:

  • wysiwyg editing of text blocks
  • merging multiple PDFs
  • extracting pages from PDFs
  • exporting pages to text, html, epub and rtf
  • adding redaction (example shown below)
  • adding bookmarks
  • adding static watermarks, including lots of built-in watermarks

For more details on Infix, please click here