[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: Printers using free software only



Am Donnerstag, 2. August 2012 schrieb Roger Leigh:
> On Tue, Jul 31, 2012 at 02:06:07PM +0000, Camaleón wrote:
> > On Tue, 31 Jul 2012 19:43:13 +1200, Chris Bannister wrote:
> > 
> >
> > > On Mon, Jul 30, 2012 at 04:51:11PM +0000, Camaleón wrote:
> > >> I just wanted to point a scenario where the jump to a PDF filter
> > >> as the default backend can have its troubles and not be nor as
> > >> good nor as simple nor as easy as the white papers say. Companies
> > >> have always showed different needs than users and these "jumps"
> > >> are seen differently when you have to hold them as user or as
> > >> admin.
> > >
> > > 
> > >
> > > The understanding I got from reading Roger's post was that if you
> > > are using CUPS, THEN you are automatically using "a PDF filter
> > > paradigm" because it **is considered superior/"more robust"**.
> >
> > 
> >
> > That's what CUPS developers seem to claim (?) but having used PS
> > printers  and PS backend as default for all these years, I'm a bit
> > reluctant about grandiloquent wordings with no more technical proofs
> > on the superiority of one on the proposed systems over the other.
> 
> If you want technical proof, please download the specs for both from
> Adobe's website and compare them.  Both are freely downloadable.
>   http://partners.adobe.com/public/developer/en/ps/PLRM.pdf
>   http://www.adobe.com/devnet/acrobat/pdfs/pdf_reference_1-7.pdf
> The wikipedia pages for both are also reasonably informative.
> 
> The fact is, PDF is the continuation of PostScript.  It's just an
> evolved form of PostScript in a binary format.  More accurately, both
> formats are implementations of the "Adobe imaging model"; until PDF
> 1.4, both of these formats implemented the same set of primitives.
> PDF 1.4 and later implement new additions to the imaging model, while
> PostScript will not see any new releases.  If you look at all the
> drawing primitives contained within PostScript, they are all right
> there in PDF.  If you take any PostScript document, you can execute
> it and transform all the drawing commands to their PDF equivalent.
> That's why it's trivial to to the conversion.  The converse is not
> always true: because PDF is a superset of the PostScript drawing
> model, and so you potentially lose information going the other way,
> because you might have to convert a single PDF primitive into multiple
> PostScript primitives which only approximate the PDF.

Roger, many thanks for taking the time to explain the switch from 
PostScript to PDF in such a great detail. I found your posts to be a 
really informative read.

Thanks,
-- 
Martin 'Helios' Steigerwald - http://www.Lichtvoll.de
GPG: 03B0 0D6C 0040 0710 4AFA  B82F 991B EAAC A599 84C7


Reply to: