Bug 647124

Summary:	gs 8.00 makes a large and slow PDF file
Product:	Ghostscript	Reporter:	Jack Moffitt <jack>
Component:	PDF Writer	Assignee:	Igor Melichev <igor.melichev>
Status:	NOTIFIED FIXED
Severity:	normal
Priority:	P2
Version:	master
Hardware:	All
OS:	All
Customer:		Word Size:	---

Description Jack Moffitt 2002-12-02 11:30:07 UTC

Originally reported by: william8000@users.sourceforge.net
gs8 (with -sDEVICE=pdfwrite -sOutputFile=x.pdf -c
.setpdfwrite -f subway.eps) makes a large PDF file.  I
have an EPS file for a Subway ad illustrating the
problem available for ftp in
ftp://nscs.fast.net/pub/gsbug/ as
gs-pdf-bug-subway-ad.eps.bz2

The EPS file is 4.9 MB uncompressed, while the PDF is
2.3 MB compressed.

The PDF file is valid, but not coded efficiently.  For
example, on my
300 MHz Pentium RedHat Linux 7.1 system, gs8 views the
EPS in 2 seconds but the PDF in 3 minutes 37 seconds. 
gs views the EPS over 100 times faster than the PDF. 
xpdf-2.00 renders the PDF in about 35 seconds, but the
letters have jaggies.  I am told that Acrobat Reader 5
renders the PDF slowly as well.

The EPS file contains a number of embedded EPS files. 
The balloons are made by an EPS file called something
like "balloons & streamers spot.eps".   That file was
made in Photoshop and saved with "PS color management"
enabled.  Photoshop draws the image with code that you
can find by searching for
"PhotoshopDuotoneColorSpace".  What ever it does, it
seems to be a worst-case for gs's PDF output.

When we try to open the resulting PDF using InDesign
1.5 on MacOS 9.2.2, we get the message:
  Error encountered while drawing PDF page.
  Page may be damaged.  Resave the PDF
  document and try again.

We suspect that PDF is valid but so complicated that
InDesign is running out of memory.

InDesign and Quark can both open the PDF generated by
Distiller from the EPS file.  The PDF generated by
Distiller is about half the size of the PDF created by
gs8.

William
williambader@hotmail.com
http://williambader.com

Comment 1 Alex Cherepanov 2002-12-03 09:37:44 UTC

Comment originally by alexcher@users.sourceforge.net
Logged In: YES 
user_id=65750

GS 8.00 converts the image in /CIEBasedA color space to a
zillion of small rectangles. This doesn't happen with the
image in /DeviceGray color space. Attached is a simplified
sample file.

Comment 2 Igor Melichev 2002-12-09 03:08:46 UTC

Comment originally by igorm@users.sourceforge.net
Logged In: YES 
user_id=79484

Patch
http://www.ghostscript.com/pipermail/gs-cvs/2002-
December/002701.html

Comment 3 Jack Moffitt 2002-12-12 16:01:06 UTC

Comment originally by william8000@users.sourceforge.net
Logged In: YES 
user_id=660793

i applied the patch from igorm to gs8.00 and rebuilt it.
For the same subway file on the same Linux PC,
gs now generates a 421 KB PDF that views in 4 sec with gs 8.00
and 9 sec with xpdf-2.01.
On our Mac, Quark and InDesign are both happy with the pdf,
and it came out OK when we printed it from Quark.
Thanks for fixing the problem!