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Re: Series of PDF/UA video tutorials

for

From: Kelly Lupo
Date: Mar 22, 2016 11:33AM

I see - thank you for the explanation and history!

Was there an accessibility reason to disallow transparent effects at the
time, or was it purely technical (IE: difficulty in tagging objects
appropriately), and advances have made this possible under PDF/A-2?

Kelly

On Mon, Mar 21, 2016 at 5:58 PM, Olaf Drümmer < <EMAIL REMOVED> >
wrote:

> Hi Kelly,
>
> > On 21.03.2016, at 20:49, Kelly Lupo < <EMAIL REMOVED> > wrote:
> >
> > - I might also suggest explaining why you did *not* choose to check
> > "Create PDF/A-1a:2005 compliant file." I was curious myself as to why
> you
> > did not, so I imagine other beginner "newbs" may be as well. :)
>
> one main reason is that PDF/A-1 disallows the use of ‘transparency'. If
> transparent objects (think 'text highlighted in yellow' or ‘drop shadow
> effect' etc.) are present in a Microsoft Office these objects (and those
> that overlap with these transparent objects) will have to be replaced by
> one or more objets that do not use transparency but still look the same. In
> numerous cases this could mean that text or vector objects are rasterized -
> which then makes it impossible to tag these properly.
>
> Another important reason is that PDF/A-1 limits the number of tag objects
> you can have to 8191. This may sound like a lot but will easily be exceeded
> in longer documents.
>
> PDF/A-1 had been released in 2005 and was based on PDF 1.4. In the
> meantime, PDF/A-2 - which does allow transparency, does not have a limit of
> 8191 tag objects, and is based on PDF 1.7 per ISO 32000-1 - has been
> released (in 2011) and is recommended over PDF?A-1 for all digital born
> documents (as opposed to for example scanned documents where PDF/A-1 can
> still be quite OK though PDF/A-2 can be used as well for these).
> Unfortunately Microsoft did not find the time so far to also implement
> support for PDF/A-2.
>
>
> For those not familiar with the PDF/A family of ISO standards - they have
> been invented to support long term preservation of electronic documents and
> are widely used in archiving.
>
>
> Olaf
>
> > > > >