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From: Peter Murray-Rust <pm286@cam.ac.uk>
Date: Thu, 29 Dec 2016 09:33:23 +0000
Message-ID: <CAD2k14ODfwUzEEQ72hegByCiZMAkhNrcLdiFE3RQTOT5-zfB7g@mail.gmail.com>
Subject: What is a "bead" and how is it created/used?
To: "users@pdfbox.apache.org" <users@pdfbox.apache.org>
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I have tried to find out from the PDF specification what a bead is, but I
haven't foudn a clear account. (That may be my fault or it may be the size
of the spec!). My understanding is that beads give the reading order of
chunks of the document (independently of the coordinate system).

Here are some questions. If they are wildly ignorant please correct me
gently.

* Where and how are beads created? Are they only created by authoring
software or can readers deduce them?
* where is bead information stored in a PDF and how can it be extracted?
* are PDF readers expected to implement bead-aware software? What is the
abstract model of a bead in a reader?
* are there other ways of transmitting "chunks" other than beads?

TIA

P.


-- 
Peter Murray-Rust
Reader Emeritus in Molecular Informatics
Unilever Centre, Dept. Of Chemistry
University of Cambridge
CB2 1EW, UK
+44-1223-763069

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