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Re: Australian Government guidance on PDF Accessibility

for

From: Birkir Rúnar Gunnarsson
Date: Jan 5, 2011 6:45PM

You folks certainly have a point, but what I had in mind was more an
unintentional alteration of a file by a user forwarding it.
It'd be easy to select and delete text, and it could even happen by
accident. Any alteration of a .pdf file would have to be intentional.
I just recently openned a Word 2007 file with Jaws and, for some
bizarre reason, Jaws deleted all spaces between paragraphs (the . and
the first letter in the following sentence) in the entire document.
I still have to figure out how in the world that could have happened,
and that is not a subject for this list, but my colleague spent an
hour fixing the file after I emailed it to him.
Thanks
-B

On 1/6/11, Duff Johnson < <EMAIL REMOVED> > wrote:
> On Jan 5, 2011, at 7:25 PM, Webb, KerryA wrote:
>
>> Birkir wrote:
>>
>>> It also open the possibility for document alterations.
>>>
>>
>> I hope you don't mind if I jump on this one; it's a pet peeve of mine.
>
> Jumping? I LOVE jumping! :-)
>
>> Some of our people insist on publishing in PDF because "it can't be
>> altered". Often it's people who have to publish contracts or legislation.
>
> C'mon, these aren't technical people we're talking about. They mean that
> PDF "can't be altered" in the sense that it's not a word-processing file.
> They're not making a technical claim about the degree of encryption, or lack
> thereof, in their PDFs.
>
> Their belief is an understandable (if erroneous) extension of the basic
> truth of PDF (accessibility aside - for a moment!); that it's
> self-contained, and appears the same way to all users on all systems.
>
> PDF files don't suffer the indignities of (for example) page-breaks getting
> screwed up when you send a DOC from A to B.
>
> A simple way to rid users of their invalid assumptions about the
> inviolability of PDF is simply to ask them to send you one of their files.
> You then edit it in a dramatic way (say, remove every other line from the
> first para) and send it back to them 2 minutes later... all the while making
> the point that you're using commercial, off the shelf software that anyone
> can buy.
>
> That usually does the trick.
>
>> I don't buy this. You can do a lot with computers; you can even mock up a
>> genuine-looking altered PDF, so that argument just won't wash.
>
> Certainly, people believe all sorts of things - but it's nice to know when
> PDF can actually live up to the user's imagination. It's simply that it
> doesn't happen by magic.
>
> A PDF file may be digitally-signed with a CA (Certificate Authority)
> providing authentication of the file's origin. The signature itself provides
> assurance to the end-user that the file has not been altered after
> application of the signature.
>
> Here's one such example:
>
> http://www.gpoaccess.gov/usbudget/fy11/pdf/budget.pdf
>
> Try doing that with HTML. ;-)
>
> Duff.
>