Return-Path: Date: Thu, 18 Oct 2007 10:33:45 -0700 (PDT) From: Jim Carter To: BlueZ development In-Reply-To: <471730B2.3030606@free.fr> Message-ID: References: <719D5CCC2F6E3644B0A9F5C9B1D00088038171C2@esebe104.NOE.Nokia.com> <471730B2.3030606@free.fr> MIME-Version: 1.0 Subject: Re: [Bluez-devel] PATCH1/2: bluez-utils - fix-a2dp-buffer-constraints Reply-To: BlueZ development List-Id: BlueZ development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Sender: bluez-devel-bounces@lists.sourceforge.net Errors-To: bluez-devel-bounces@lists.sourceforge.net On Thu, 18 Oct 2007, Fabien Chevalier wrote: > > On 12 Oct 2007, Kai Vehmanen wrote: > > Current code seems to gather samples-to-be-sent in a buffer, > > and when a threshold (a2dp->codesize or cfg.pkt_len) is reached, > > a packet is then sent right away. So in other words, application > > cannot really prefill more data than one packet worth, and most of > > the allocated buffer space gets never used. > > Well, application can prefill more data, the data gets send immediately > to the headset, and buffering will happen at headset side. The issue is > if the buffer size as seen by the application is bigger than the real > headset buffer size, and the application waits for the buffer to be > almost empty before to refill it, then audio cuts might happen. :-( I remember a month or two back, someone said that the A2DP profile was weak on flow control, requiring the source (ALSA) to send data at an even rate. If the headset's buffer is full can it cork the stream? Or will the additional data just overwrite data already at the headset? With bluez-utils-3.19 (3.20 is latest) I'm having consistently good results sending to the Bluetooth ALSA device, with neither silent gaps nor lost chunks. But I'm seeing corruption when going through PulseAudio, which is attributed to an unknown formatting or parameter issue and is being dealt with on their mailing list. James F. Carter Voice 310 825 2897 FAX 310 206 6673 UCLA-Mathnet; 6115 MSA; 405 Hilgard Ave.; Los Angeles, CA, USA 90095-1555 Email: jimc@math.ucla.edu http://www.math.ucla.edu/~jimc (q.v. for PGP key) ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Bluez-devel mailing list Bluez-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bluez-devel