[gs-devel] Pdfx3 fails preflight

[Marc Pelletier]

 Ken,

Thanks for your reply. 

Your numbers sound right. I don't think there is any transparency, maybe
on some of the pngs, but they tend to be smaller.

Yes a pdf is created and I can view it and print it from here. When I
sent a sample to the client it didn't print correctly though, as
apparently the fonts weren't embedded. All of the text was reduced to
1's and >'s at his end. He is sending the pdf directly to an hp6100
plotter without using adobe anything.

Opening the pdf in acrobat consumes a fair amount of memory, so I
suspect it is uncompressing the contents into a huge bitmap internally
as you describe.

Since I posted that message, I have tried a different driver the HP6100
driver and was able to distill the output from it. The ghostscript
conversion was the same as previously though, it runs without error but
the pdf fails preflight after consuming all of the memory. The distilled
version of the pdf is less than half the size of the gs version and
renders much more quickly.

Now that I've successfully distilled I think I can rule out the ps, it
is clearly my parameter files that must be wrong.

Any ideas?

Marc



-----Original Message-----
From: Ken Sharp [mailto:ken.sharp at artifex.com] 
Sent: April 30, 2010 12:49 PM
To: Marc Pelletier
Subject: Re: [gs-devel] Pdfx3 fails preflight

At 10:09 30/04/2010 -0600, you wrote:


>error. There must be something messed up in the pdf because it is only
>25 Meg. The ps was emitted from the hp designjet 1050 postscript
driver.
>Its a 33x55 inch 300  dpi map with a dozen or so embedded pngs and
bmps.
>The ps file was about 330 Meg.

If its being rasterised, as it will be if the file contains any 
transparency (PDF/X doesn't currently support transparency), then you
are 
potentially creating a humungous bitmap.

33 inches @300 dpi = 9,900 pixels per scan line
50 inches @300 dpi = 15,000 scan lines

15,500 * 9,900 = 148500000 pixels. Assuming RGB output that means 3
bytes 
per pixel. 3 * 148500000 = 445,500,000 or ~440 MB.

If there's a lot of white space, (seems reasonable with a map) or not
very 
large areas of transparency, that could give you a 25MB output file 
(starting with a 330MB PS file apparently, so there must be a lot of
data 
in there).

You seem to be implying that a PDF file is created, is this true ? And
it 
can be opened and viewed in Acrobat ? The only problem is that the
Acrobat 
preflight can't handle it ?

Sounds to me more like a problem with Acorbat's preflight software than 
anything else. Even if there were 'something messed up' in the PDF file,

the preflight tool should tell you that.



                     Ken