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Dear All,

After two weeks of scouring through my linearized PDFs, I finally traced
this bug down. It was not to do with the linearization hint table, but an
obscure implementation of a bug in Acrobat 5.0, documented in Appendix H,
F.2.2, item 157 in the Compatibility and Implementation Notes section (Page
976 of PDF Reference, version 1.5).

"Acrobat generates a value for the E parameter that incorrectly includes an
object beyond the end of the first page as if it was part of the first
page."

The /E parameter in the Linearization section is the offset in bytes from
the start of the file to the first object on the second page. To comply
with this "Bug" we had deliberately added the length of the first object on
the second page onto this value. This worked for quite a few PDF files but
certain files would fail, maybe because the first object on the second
page's length was bigger than usual. By removing this "Fix" everything now
worked again.

If anyone else is doing the same in their implementation of Linearized
PDFs, stop doing it! It is fixed in Acrobat 6.0. If anyone from Adobe is
reading this, can you change the implementation notes, or make Acrobat 6.0
take into account this error in Acrobat 5.0. But how many Acrobat 5.0 saved
linearized PDF files are still out there with this "bug"?

Robin Landsbert


Date: Fri, 28 Nov 2003 08:59:58 -0500
From: Mark Gavin <[EMAIL PROTECTED]>
Subject: Re: [PDFdev] Linearized PDF, Acrobat 6.0 on Windows

Robert,
  There is a mistake in the linearization hint tables.

Regards,

Mark Gavin
Chief Technology Officer
Appligent, Inc.
60 South Lansdowne Avenue
Lansdowne, PA 19050
(610) 284-4006
http://www.appligent.com

On Nov 28, 2003, at 4:38 AM, Robin Landsbert wrote:

> We have been having problems with linearized PDF files that we generate
> being displayed with Acrobat 6.0 running on Windows. When the files are
> displayed with the "Allow fast web view" preference turned on, only the
> first page is displayed. All subsequent pages are displayed as small
> empty
> square boxes. Turning the option off allows the same files with the
> same
> data to be displayed correctly. Previous version of Acrobat display the
> files correctly Has anyone come across the problem before? Is there
> some
> change to the way that PDF files need to be linearized?
>
> Robin Landsbert


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