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Re: [hybi] Payload only compression extension, again

Bjoern Hoehrmann <derhoermi@gmx.net> Tue, 26 July 2011 15:25 UTC

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From: Bjoern Hoehrmann <derhoermi@gmx.net>
To: John Tamplin <jat@google.com>
Date: Tue, 26 Jul 2011 17:25:53 +0200
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Cc: "hybi@ietf.org" <hybi@ietf.org>
Subject: Re: [hybi] Payload only compression extension, again
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* John Tamplin wrote:
>The problem is that if you don't share compression state across frames, then
>it becomes critical to not try and compress incompressible content.  Look at
>the experiment data I presented in that same thread -- it is very easy for
>frame sizes to go up if you aren't sharing compression state, so I think if
>this option is included we have to decide now how to turn off compression on
>a frame-by-frame basis rather than delaying it for a future extension.

Deflate stores uncompressed data in up to 2^15 byte long blocks like

  1 byte indicating no compression and whether it's a final block
  2 byte indicating the length
  2 byte one's complement of the length
  n byte uncompressed data as per the length

Are you saying the 5 additional byte per block are a problem?
-- 
Björn Höhrmann · mailto:bjoern@hoehrmann.de · http://bjoern.hoehrmann.de
Am Badedeich 7 · Telefon: +49(0)160/4415681 · http://www.bjoernsworld.de
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