[gs-devel] status of PDF/A support

[Ludovic Aelbrecht]

Thanks again for your helpful explanations. I've written some
additional comments in-line, below.

On Thu, Feb 26, 2009 at 17:13, Ken Sharp <ken.sharp at artifex.com> wrote:
>
> % Define entries to the document Info dictionary :
>
> /ICCProfile (ISO Coated sb.icc)   % Customize.
> def
>
> You probably won't have a file called 'ISO Coated sb.icc' and even if you
> do, it won't be in the current directory. You need to replace this with the
> name and path of an ICC profile of your own choosing.

In previous versions of ghostscript, usage of CMYK/RGB/CIE could be
specified simply through a command-line parameter, without including a
color profile (or any definition file whatsoever, for that matter). If
I understand it correctly, this is no longer possible for creating
PDF/A's.

In ghostscript-8.64\Resource\ColorSpace, there are files called
"DefaultCMYK" and "DefaultRGB". Is it correct that these files could
be used as color profiles?
So this would be correct:
/ICCProfile d:\ghostscript-8.64\Resource\ColorSpace\DefaultRGB

Right? Also, where would I go about finding such definition files for
e.g. the CIE color profile? Does ghostcript provide these?


> There is also the default 'Title' entry. If I remember correctly this gets
> overwritten by any pre-existing %%Title from the input PostScript or /Title
> entry in the Info dict of an input PDF file. You need a default, but it
> doesn't have to be 'Title'.

This would be sufficient, right? (We don't really care about filling
in the metadata fields with meaningful values.)
/Title Certified PDF


> Finally the OutputConditionidentifier may need to be altered:
>
>  /OutputConditionIdentifier (CGATS TR001)      % Customize

I've tried to read up on OutputConditionIdentifier, but can't find
much in the documentation which makes sense to me. Any place I can
find more about what this does, and its possible values?


>> We are not interested in putting metadata into the PDF file (which, if
>> I understand the file correctly, seems to be one part of the
>> PDFA_def.ps definition file). So is there a reason why we would not
>> want to use PDFA_def.ps for all our conversions?
>
> You must supply certain elements of metadata or the file won't be a valid
> PDF/A file, the default PDFA_def.ps is pretty much a minimal implementation.
> The extra keywords added as part of the patch for #690046 (eg subject and
> Keywords) for example, are optional and not required, hence not present in
> the default PDFA_def.ps.

The "Title" field we talk about above is the only required metadata
field, right?


Thanks a lot for your help.

Best regards,

Ludovic