stressfree - interoperability

Adobe releases PDF standard for ISO certification

David — Wed, 31 Jan 2007 09:46:25 +0000

On the 29th January Adobe announced it will be seeking ISO certification for the PDF 1.7 standard. Up until this point many vendors have been able to implement the PDF standard based solely on trust that Adobe will not significantly change the format and break their respective implementations. If PDF gains ISO certification then this will ensure any vendor can develop for and use the standard in the knowledge that it will not change and be 100% interoperable with other implementations of the same standard.

This is good news for governments and business as it means once certified PDF will become a permanent, unencumbered format. These characteristics will enable organisations to use PDF as an archiving medium for 2-dimensional digital documents with the confidence that no single company can dictate or control the use of the format. This is important because in the past companies like Microsoft have unduly effected the industry with their monopolistic control over formats (as evidenced by the infamous Halloween Memo).

Microsoft and Autodesk will not be too pleased at this development as both parties have formats which are competing against PDF (XPS and DWF) for user acceptance. What is not so clear from the announcement is whether Adobe's ISO ambitions cover their newly announced 3D extensions to PDF or just the well entrenched 2D format. My guess would be this week's announcement only covers 2D as 3D is no doubt still under constant development. Either way it adds pressure to Autodesk who are really pushing DWF hard as the most important medium for 2D and 3D documentation in the Architecture, Engineering and Construction space.

Deelip Menezes posted the ISO news on his blog and he got an interesting reaction from Brian Mathews of Autodesk Labs. In the comment he argues that DWF holds the advantage because it is based upon Microsoft's XML-based XPS format which is more clearly documented and more 'open' because it is in XML. This "XML good - binary bad" line of thinking ignores the fact that XML by design is significantly slower and heavier than a binary format which limits its applicability. Also it is important to remember that a format's clarity of documentation is entirely dependent on the efforts of the format creator, something Microsoft has proven notoriously bad at.

Brian also raises another point:

"PDF has always been an open specification, but has been based on a very complex binary format that takes 1000's of pages to fully document (with lots of external reference documents)."

Out of interest I downloaded the Adobe PDF specification from their website. Yes it is 1,310 pages long but this includes almost 200 pages of index and 100 pages of examples. That leaves a round about 1,000 pages devoted to the actual standard and from a quick click through I found the sections well laid out and in parts quite an interesting read (well as interesting as a standard can get). Whilst 1,000 pages is a lot there is a lot to cover and I would rather see a format span 10,000 pages and be understood in depth rather than glossed over in 500. Also another yardstick by which a good standard can be judged is how often it is independently implemented and for PDF this number is quite significant, just checkout Wikipedia's rundown.

The other issue Brian Mathews raised was Adobe's XML-based PDF format codenamed Mars:

"Adobe followed recently with an announcement that they too will be developing their own fully XML alternative to PDF. Why? Because PDF isn't open enough since it isn't XML."

Reading through the intentions behind Mars it becomes apparent that it is not so much a "PDF replacement" as Brian implies but rather a complimentary format. Why? Binary formats are difficult to index by search engines or pull data out of without pre-processing. Mars is not a rewrite of the PDF format but rather an implementation of the PDF standard using XML syntax (after all, XML is just a language syntax). This format enables quick, low overhead indexing and data manipulation at the cost of end-user speed. As a consequence Adobe are pushing this as a complimentary format and certainly not as a replacement to binary PDF. Employing complimentary file formats is not unusual, for example the Industry Foundation Classes come in both binary and XML versions to suit specific use cases.

What this all this means in the long term is still uncertain but it certainly looks like the competition is heating up.

Zamzar - Funny name, potentially interesting concept

David — Fri, 24 Nov 2006 02:18:06 +0000

Although you wouldn't think it by the name Zamzar is a Web-based file conversation tool. File conversion tools are not new but the fact that it is Web-based is. Zamzar supports are variety of file conversions that fall under document (including Word and Excel), video, image and music categories.

Traditionally file conversion has operated under a fairly conventional model, you pay a license fee and are given a piece of software that sits on your computer that undertakes the file conversion. Zamzar uses a different approach, it is completely free and rather than downloading a piece of software to your computer your file is uploaded to their server for conversion. On completion a link is emailed to you and by following it your newly converted file can be downloaded. The financial model at work here is advertising and the market they are targeting is the casual user who cannot justify the cost or complexity of a fully blown piece of conversion software sitting on their desktop.

Where things get interesting is if this concept was applied to the AEC industry. Currently the industry leader for CAD file conversion is Right Hemisphere with their Deep Exploration/Server suite. The problem for these guys is that their software is so complex and powerful that most AEC companies do not need them when it comes to file conversion. Instead companies either own multiple pieces of CAD software (i.e. one license of AutoCAD in the office 'just in case') or they simply will not accept files of a certain type (many projects specify allowed file types for third parties). What would be really interesting for the AEC industry is if the power of the Right Hemisphere conversion software could be made available in a model like Zamzar's (i.e low cost and Web-based).

Low cost, Web-based CAD file conversion would save the industry time and a great deal of money, the only barrier would appear to be the lucrative nature of products like Deep Server and the unwillingness of its owners to loose $100,000+ license fees and adopt a new, more approachable and affordable delivery model. One thing to note about CAD file conversion is that it is extremely processor intensive, any Web-based CAD file conversion system would need to use some form of load distribution system otherwise if files could not be converted in a reasonable amount of time then the chances are it will not be used. One cost effective way of achieving this would be to utilise a flexible, load balancing system like Amazon's Elastic Compute Cloud (EC2) for the actual file conversion process.

The chances of something like this coming into fruition is pretty slim but if it did it could really shake up the notion of CAD compatibility and save the AEC industry an immense amount of time, money and pain.

Interoperability problems cost Airbus time and money

David — Fri, 13 Oct 2006 01:49:35 +0000

Given all the attention to interoperability within the AEC industry over the last ten years you would have thought Airbus would have had a handle on the idea. Unfortunately it would appear that even though they are using Catia for the bulk of their design development work the significant format differences between version 4 and 5 plus management mishandling has resulted in the delay of the A380 and millions (if not billions) of dollars of losses. It would appear that even though Boeing's aircraft may not be as imagination inspiring as the A380 their CAD processes are a lot sounder.

Adobe Acrobat 3D: a very real threat to DWF

David — Mon, 01 May 2006 23:57:38 +0000

Architosh and CADwire have feature reviews of Acrobat 3D and I must say it sounds really, really good. I am big fan of the PDF standard but not of recent Adobe Acrobat releases (the term 'bloatware' springs to mind). When I first heard that Adobe where planning on including 3D support in Acrobat I assumed it would be a token gesture in order to differentiate it from its 2D PDF competitors like Foxit (my favourite Windows pdf reader). I began to change my mind and think it was something a little more serious when AutoDesk suddenly seemed to get very anti-PDF when it came to exchanging building information.

Reading the reviews of Acrobat 3D I can see why the people at AutoDesk seemed so worried, it has one major killer feature that really sets it apart from all the competition, a 'print screen' equivalent for 3D models. This 3D importing feature does not work at the software application level like most data importers, it skips all the difficulties associated with data format translation and plucks the 3D information directly out of the OpenGL buffer. This is a really intelligent move from Adobe, it gives their product a degree of model importing support perhaps only rivaled by Right Hemisphere.

From a user perspective it means they can pluck 3D models out of a variety of applications and easily exchange them between others and thanks to Adobe's ubiquity on the desktop there will be almost no concerns about the recipient not being able to read the pdf file at the other end. From an IT manager's perspective its easier to go with Adobe than AutoDesk's DWF because PDF and Adobe Reader are in the mainstream already (according to Adobe they've distributed 1.5 billion copies) so there is no need to train users or install additional software (like AutoDesk's very fat DWF viewer). Vendors like Bentley and Graphisoft must be happy as their products will have Adobe Acrobat 3D support without having do a thing. Plus now that there is a ubiquitous alternative to DWF as a 3D document medium (above and beyond the DWG/3DS data formats) they will not have expend the time and resources implementing DWF support in their own products, if anything these resources will be put into improved 3D PDF support.

This approach does have its drawbacks, plucking data straight out of the OpenGL buffer is not the most accurate method hence you could not trust measurements taken directly off the model if building it. DWF supporters point this out along with a number of other PDF shortcomings, but at the end of the day whilst technically not the best solution, PDF (like Microsoft Office) gets the job done and is used by the majority of people.

Why are AutoDesk pushing DWF? As their own diagrams illustrate it is the glue that holds the entire AutoDesk product silo together, without it they open the door for other competitors to seamlessly replace AutoDesk products within AEC teams. This competition is not a bad thing however, I think the two rival formats are doing more for interoperability between CAD suites than what ten years of IFC development has ever done.