RE: EXI compression

Hi Marco,

A value channel contains a series of value content items.

The "value" content items are defined here.
http://www.w3.org/TR/exi/#key-valueContentItem

Each value (i.e. value content item) is encoded per the associated schema
datatype if any, otherwise as a string. The schema datatypes and their respective
representations are shown in table:
http://www.w3.org/TR/exi/#builtInEXITypes

When the datatype is string, or when datatypes are not available for values,
those values are encoded as strings per the encoding rule defined this section:
http://www.w3.org/TR/exi/#encodingString

There's nothing special about the value encoding when compession is in effect.
For strings, when an entry was found in a string table, it is the the index that is
encoded, which in turn represents the value. When an entry was not found in
a string table, the literal string is encoded with length prefixed.

Hope it helps,

-taki

-----Original Message-----
From: public-exi-request@w3.org [mailto:public-exi-request@w3.org] On Behalf Of Marco Wegner
Sent: Monday, March 10, 2008 8:47 AM
To: public-exi@w3.org
Subject: EXI compression


Hello group,

I have a question concerning EXI compression, especially the contents of
value channels. If I understand correctly, then these channels contain
only the (string) values themselves if these have been value misses. And
these channels contain neither the string lengths nor the string table
indices in case of (local or global) value hits (which would all go into
the structure channel).

In other words: value channels contain exactly the same information as the
string tables.

Is this correct?

Thanks in advance and kind regards,
Marco

Received on Wednesday, 12 March 2008 23:46:38 UTC