[Fellowship Zurich] Fwd: PDF Readers...

[Robert Ribnitz]

Das folgende ging an die falsche liste...

Grüsse Robert

---------- Forwarded message ----------
From: Robert Ribnitz <robert.ribnitz at gmail.com>
Date: Sat, Sep 17, 2011 at 2:00 PM
Subject: PDF Readers...
To: switzerland at fsfeurope.org


Hello there, here's a tentative list of what PDF supports, and what
therefore a PDF reader must also support:


   - Passwords/Encryption and digital signatures  (MD5, RC4,AES, SHA-1,
   SHA-256, SHA-384, SHA-512 and RIPEMD160)
   - Interactive elements (checkboxes, radiobuttons), "fill-in forms" (as in
   text lines & text boxes)
   - embedded file streams ("attachments") of any type
   - ICC and DeviceN color spaces, several of the features present in
   Postscript Level 3
   - Annotations
   - Masked images, images with alternate representation, smooth shading,
   transparency
   - Unicode charaters
   - import content from one PDF into another
   - PCKS #7 support with SHA-1 and RSA signaures
   - Use of usage rights does not require encrypting the document
   - Possibliity to hide/show sections of text, or review them
   - JavaScript support
   - Support for Universa 3D and OpenType
   - Cross-document linking


ISO 32000-1:2008 specifies a PDF version (PDF 1.7, as supported by Acrobat
Reader 8)

The following can be controlled by usage rights:

   - Save the PDF, possibly with annotations, form data
   - Import form data
   - Export form data


DRM can limit copying, editng, annotations or printing; the use of DRM does
not require document encryption.

see http://en.wikipedia.org/wiki/Portable_Document_Format

If we want to give users a chance of using an "alternate" reader, we must
provide them with one that supports these features (or at least the more
common of them).
-------------- nächster Teil --------------
Ein Dateianhang mit HTML-Daten wurde abgetrennt...
URL: <http://lists.fsfe.org/pipermail/zurich/attachments/20110923/dd8b544a/attachment.htm>