Message-ID: <459D10F6.8090509@uni-ulm.de>
Date: Thu, 04 Jan 2007 15:36:38 +0100
From: Siegbert Baude <siegbert.baude@uni-ulm.de>
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To: bluez-devel@lists.sourceforge.net
Subject: [Bluez-devel] SBC codec, joint stereo mode
Reply-To: BlueZ development <bluez-devel@lists.sourceforge.net>
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Hi,

I have a question with regard to joint stereo mode in SBC. According to
the A2DP spec. p. 53, sec. 12.4 "Syntax" in the frame_header there is
one bit RFA after the join[sb] bits. In the example implementations of
the SBC codec I got (one from TI, one from iAnywhere AV SDK, one from
the ALSA-Bluetooth project), this bit is however never accounted for.
Also in the sbc_test_14.sbc example you can download from bluetooth.org,
I find at offset 04FB the beginning of the frame as 9C7F797BBC87, where
the first bit of "87" should be this RFA bit (as this example uses 8
subbands). P. 11, sec. 1.3.2.1 "RFA" however says, RFA bits should be
set to zero, which is not the case for "87".

So is this RFA bit actually used or not?

Ciao
Siegbert

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