[Printing-japan] [gs-devel] upcoming freeze for the 8.63 release - Make CUPS filters/PPDs PDF ready

[Till Kamppeter]

Koji Otani wrote:
> From: Till Kamppeter <till.kamppeter at gmail.com>
> Subject: Re: [Printing-japan] [gs-devel] upcoming freeze for the 8.63 release - Make CUPS filters/PPDs PDF ready
> Date: Tue, 22 Jul 2008 20:43:22 +0200
> Message-ID: <48862A4A.2030103 at gmail.com>
> 
> till.kamppeter> 
> till.kamppeter> Mike, Otani-san, WDYT, how should the architecture of the psto... CUPS 
> till.kamppeter> drivers be changed to get working pdfto... or pdlto... CUPS drivers, as 
> till.kamppeter> it seems that one cannot use PostScript options (options which insert 
> till.kamppeter> PostScript code into the data stream) any more?
> till.kamppeter> 
> till.kamppeter> Probably the driver filter (pdfto... or pdlto...) and also pdftopdf 
> till.kamppeter> should read the options from the 5th argument of the command line and 
> till.kamppeter> then apply them at the right place, for example in the Ghostscript 
> till.kamppeter> command line.
> till.kamppeter> 
> till.kamppeter> What is the concept here?
> till.kamppeter> 
> till.kamppeter>     Till
> till.kamppeter> 
> 
> I think the best is follow.
> 
> (1) Define how to specify Job options in PDF data stream.
> (2) Develop a library handle this options. (JTAPI or it's subset ?)
> (3) Each filter handle Job options in PDF data stream using that
> library.
> 
> But, this needs development cost and time. So, for the time being each
> filter should handle the options from the 5th argument of the command
> line as you wrote.
> 
> imagetopdf, pdftopdf, pdftoraster, pdftoopvp already handle command line
> options.
> 

As some PostScript-emitting applications do not supply the option 
settings separately (as arguments for the CUPS library function call to 
print a job) but rather embed them in the PostScript data stream, we 
must modify the pstopdf filter so that it extracts the option settings 
embedded in the PostScript data stream and make them somehow available 
for the subsequent filters. Mike, is that possible with CUPS?

> pdftopdf and imagetopdf insert  pdftoopvp specific Job options data
> into PDF data stream acording to PPD descriptions.

Otani-san, how do such options look like in the PPD files? How do they 
get embedded into the PDF data stream? What gets embedded? Key/value 
pair of the option setting? PDF code? ...?

    Till