Creating and Publishing Secure PDF files

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Creating and Publishing Secure PDF files

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Creating PDF files

For PDF generation we recommend use of Adobe’s commercial PDF creation tools (e.g. Adobe Acrobat Pro) or a product such as PDF Creator Plus (from Peernet Inc). The PDF creator in OpenOffice is also excellent and fast. Microsoft Office 2007 and later editions provide a Save As PDF facility (with various options for PDF creation). In many instances this will produce good files, but it can create files that leave lines and boxes on-screen and result in format errors. If this is the case with your files, use Adobe Acrobat X instead and the files will be OK. The use of form fields (e.g. buttons) as links and the use of transparency in images (see further, below), is not recommended as it may not work as expected on all platforms.

PDF files should be "transparency flattened" in most cases, otherwise they may not display correctly on all platforms. Adobe's help facility explains this as follows:

"When your artwork contains transparency, Acrobat performs a process called flattening before printing or saving the artwork. Flattening cuts apart transparent art to represent overlapping areas as discrete pieces that are either vector objects or rasterized areas. As artwork becomes more complex (mixing images, vectors, type, spot colors, overprinting, and so on), so does the flattening and its results. Flattening occurs whenever you print a document with transparent objects or export to a format other than Adobe PDF 1.4 (Acrobat 5.0 and later). Transparent objects are flattened according to the settings in the Advanced Print Setup dialog box. Flattening represents overlapping areas as either vector objects or rasterized areas."

If a PDF does exhibit problems (e.g. non-display or incorrect display of some pages) try using the flattening facilities in Adobe Acrobat (using the Tools menu, Print production facility for Flattening, or the Advanced menu, PDF Optimization option).

Another aspect of PDF files created using Adobe software is that they may include "Adobe-specific" features - indeed, many have suggested that PDF is not a standard document format at all, because it is really a huge collection of specifications and unspecified structures and attributes that really reflect Adobe's own product set rather some independently agreed international standard.

It is very important to note that some commercial PDF creation software and PDF writers produce very fragmented PDF files (e.g. with 20,000 image fragments for a single page) - with some PDF readers this may not be especially noticeable but for Drumlin and many other readers, good quality files are essential. If in doubt use the Adobe Acrobat software, as this definitely creates good files. If you have an existing poor PDF you can usually open it in Acrobat and then use the Reduce file size and/or PDF Optimizer options, or print it to the Adobe PDF printer using Standard settings to produce a very acceptable final PDF. If your files have open and/or owner passwords set using Adobe Acrobat or similar software, please remove this security before using Drumlin to create secured files.In general, security settings that are defined in the source PDF are ignored by Drumlin - we use our own encryption and security framework.

Files created using specialist publishing packages, such as Adobe InDesign, tend to produce very large "Print Quality" PDF files as standard. For eBook publishing select the option when creating the PDF (e.g. via the Export facility in InDesign) that generates small files, otherwise the resulting file may be very large and difficult to downsize. It is worth bearing in mind that most computer screens have a resolution of less than 100dpi, so creating very high resolution output is of limited benefit to those viewing the results. Modern portable devices may have screen resolutions greater than 200dpi.

Secured PDF files, which have the file extension .DRM or .DRMX or DRMZ, are created using the main Drumlin PDF reader/Publishing using the File menu, Publish... options - see Secure PDF Publishing facilities for more details. DRMZ files are a special variant of DRMX files (iPAD/Android compatible option is ticked) created for use by our Javelin readers on iPAD, PC and Mac computers. Once a DRMX has been created it can be used directly with the Javelin software for Windows or Mac, or wrapped into an exe using Javelin for Windows, via the File Menu, Publish options... "Create exe" item. Note that if this option is not available on your software installation you can contact us to request that your copy of the software be enabled for this feature. This facilitydoes not create exe files that can be read on a Mac computer.

If you have created a single secure file using Drumlin an authorization code is provided automatically (for testing, with usage count set to 5) or you can request test codes from Drumlin Security. If you have selected multiple documents to publish then each one is created in turn and test authorization codes are not generated. Authorization codes for testing and production usage are typically created using the AdminApp program.

To view fully secured PDFs (files you download or have been sent that have a .DRMX or DRMZ extension) you will need to use the Drumlin File menu, Authorize option (.DRMX files) or File menu, Open option (for Javelin, .DRMX and .DRMZ files), or the file can be "double-clicked" in Explorer or from the Mac desktop to open them. This requires input of an authorization code, supplied to you by the document publisher, and once used will save the readable document with the same filename and a .DRM extension (for Drumlin users) or just as the DRMX or DRMZ (authorized) for Javelin users. To create your own secured PDFs use the File menu, Publish option. You only need to authorize such documents once – after this first time the document is available for use and you can open it any time you wish (subject to the publisher's settings).

Currently single file secure publishing is limited to c.300Mbytes per file. For Javelin we recommend files that are no larger than 50Mbytes. Publishers with larger files are advised to use the standard Adobe Acrobat ‘reduce file size’ options and/or optimization options if they have larger files than this, or to split these very large files into smaller sections using either Adobe Acrobat or one of the widely available PDF Splitter programs (e.g. Similarly, publishers who are considering publishing files with >2000 pages may wish to consider splitting these for speed and manageability, depending on their content and experience having tested them using Javelin on the target platforms.

UserIDs and DocIDs

When you register a copy of Drumlin our server assigns you a unique userID. When you publish a secure PDF your userID forms part of the information about that particular secure PDF (collectively such information is known as the file "metadata"). Your userID is provided to you by email when you register and can be seen at any time via the Drumlin Help menu, About form. In the example below the userID is the last part of the registration code, i.e. 404 in this case. This information is important, because the system recognizes that a PDF file called "myfile.pdf" published by userID 404 is DIFFERENT from a file with the same name but published by a different user, say userID 2079. Notice that this form also shows your username, the name you used when registering. This information was confirmed to you at the time of registration but is always accessible here. It is also used if you wish to use the online user login facilities.


DocIDs are assigned to newly published secure PDF files. DocIDs, like userIDs, are also unique. If userID 404 publishes a file myfile.pdf it may be assigned a DocID of 23901, whereas if userID 2079 does the same thing a moment latter they will be assigned a different DocID. For this reason it is important that when you order authorization codes or ask for code resetting you ensure you include your user details as well as the document details (name and DocID), thus avoiding any confusion. You can always view your docIDs, names etc. using the Drumlin software Tools menu, Document history.

If you re-publish a secure PDF to create an updated version of an existing DRMX or DRMZ file, the DocID will be unchanged as long as (a) the source PDF filename you use is unchanged, only the content is changed, and (b) you do not click on the option to "Keep previous version". It is always best to try and keep the same DocIDs if you require authorization codes, because each code issued is specific to a unique DocID - existing issued codes will continue to work and you will not have to order new codes. Drumlin Javelin "Click and Go" exe files are created from DRMX files (have the DRMX file embedded in them) so use the same DocID as the source DRMX file. If necessary/on request, we can re-assign authorization codes that you have generated or requested, so that unused codes will work on a different document (e.g. an updated version of an original document, but which has a different docID).

When a DRMX or DRMZ file or exe file is being authorized by an end user, and when it is being viewed, the DocID information is provided on screen. Within the Javelin reader for Windows this information together with additional details is provided via the Help menu, About form. In Javelin for Mac this is provided via the Properties form, DRM settings. On the iPAD and Android devices this is accessed via the Information button adjacent to the file, DRM Settings tab.

Obtaining additional authorization codes

For details on authorization of Drumlin's secured PDFs see the Authorization section. To obtain additional authorization codes order these via the Store page:

Email specifying the document or documents for which you require authorization codes and your UserID (if in doubt, this is provided in your registration email and on the Help menu, About... form). For DRMX or DRMZ and EXE files your authorization codes will then be sent to you as a text list by email. For DRMZ files 9 alphanumeric codes are used, for example: abc123def, whereas for DRMX files 20 character codes are used, e.g.: Code: 6WxZSdPng8aD4SdufKuf

On request these codes can be sent to you as an email attachment in the form of a secure .DRMX file. Note that authorization codes will only be supplied directly to the document publisher using the email address provided at the time of registration. Codes can be re-assigned by Drumlin Security on request from the publisher, and codes can be reset if necessary, again on request. For Subscription Service customers an AdminApp may be made available so that codes can be generated by the publisher without having to contact Drumlin Security Ltd.