Return-Path: Message-ID: <492539BF.5040303@powercraft.nl> Date: Thu, 20 Nov 2008 11:19:43 +0100 From: Jelle de Jong MIME-Version: 1.0 To: Brad Midgley CC: linux-bluetooth@vger.kernel.org Subject: Re: possible sbc codec bug with audio glitches References: <4920099A.9030109@powercraft.nl> <4920929A.30703@powercraft.nl> In-Reply-To: Content-Type: multipart/mixed; boundary="------------020305090808040206010308" Sender: linux-bluetooth-owner@vger.kernel.org List-ID: This is a multi-part message in MIME format. --------------020305090808040206010308 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Brad Midgley wrote: > Jelle, > > Everything in the codec is symmetrical between the two channels unless > using joint stereo mode. In joint stereo, if it saves space, we encode > the difference between and the sum of the channels instead of the > individual channel content. It's conceivable that an overflow here > might be manifest differently between the two channels. > > It looks like you can use a parameter "mode" in the alsa config and > set it to either "stereo" or "joint" > > If you can narrow down the distortion to one of these cases that would be handy. > > Do you have an mp3 I could try to hear the problem? > > Brad Thank you Brad for taking the time to answer. I have tried the mode joint and mode stereo [1] for a few days but I cant hear any difference and the small glitches are still there. I posted a small audio segment that has the problem in my first post: http://sourceforge.net/mailarchive/message.php?msg_name=4819B1A7.2070702%40powercraft.nl http://filebin.ca/pugrs/glitch.wav Thanks in advance, Jelle > On Sun, Nov 16, 2008 at 2:37 PM, Jelle de Jong > wrote: >> Brad Midgley wrote: >>> Jelle >>> >>>> The strange thing is that I can only hear the glitches on the right side >>>> of the headset. >>> That is very strange it is only on one side. Do you know if you were >>> you using the joint stereo setting in the codec? >>> >> Thank you Brad for taking the time to read and answer to my question, >> this is really appreciated. I dont exactly know what you mean with joint >> stereo settings in the code? >> >> I use the bluez git build on 2008-11-06. The only info I got is from the >> bluetoothd running in debug mode, please see the attachment for more >> information. >> >> I hope the below section is the most relevant? >> >> config a2dp - device = 00:0C:55:D1:C9:78 access_mode = 2 >> codec sbc - frequency = 1 channel_mode = 1 allocation = 1 subbands = 1 >> blocks = 1 bitpool = 44 >> a2dp_source_config: selected SEP 0xb81b1020 >> avdtp_ref(0xb81acbf0): ref=3 >> setup_ref(0xb81b62a8): ref=1 >> avdtp_set_configuration(0xb81acbf0): int_seid=1, acp_seid=1 >> >> Thanks in advance, >> >> Jelle --------------020305090808040206010308 Content-Type: application/x-sh; name="setup-bluetooth-motorola-s805.sh" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="setup-bluetooth-motorola-s805.sh" #!/bin/bash echo "setup-bluetooth-motorola-s805.sh" echo 'pcm.headset { type bluetooth #~ device 00:0D:18:A0:35:70 #~ device 00:53:53:FB:7E:9C # Nokia BH-801 device 00:0C:55:D1:C9:78 # Motorola S805 #~ device 00:0D:FD:18:6E:3C # Motorola S9 #~ device 20:07:09:15:A9:5A # Samsung WEP210 profile hifi #~ profile voice #~ profile auto mode stereo #~ mode joint } pcm.softvol { type softvol slave.pcm headset control.name Headset control.card 0 } pcm.!default { #~ type hw #~ card 0 type plug slave.pcm softvol }' > ~/.asoundrc #~ sudo /etc/init.d/bluetooth restart #~ sudo /etc/init.d/alsa-utils restart echo "done, you can close this windows now" exit --------------020305090808040206010308--