From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gustavo da Silva Serra Subject: Re: Problem with aloop Date: Fri, 09 May 2008 09:56:09 -0300 Message-ID: <482449E9.3000405@tet.com.br> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from einstein.tteng.com.br (mail4.tet.com.br [201.47.194.114]) by alsa0.perex.cz (Postfix) with ESMTP id 2E0422443D for ; Fri, 9 May 2008 14:56:14 +0200 (CEST) Received: from localhost (localhost.localdomain [127.0.0.1]) by einstein.tteng.com.br (Postfix) with ESMTP id F03661204C6 for ; Fri, 9 May 2008 09:56:12 -0300 (BRST) Received: from [192.168.0.84] (gserra.tteng.com.br [192.168.0.84]) by einstein.tteng.com.br (Postfix) with ESMTP id E117D12000E for ; Fri, 9 May 2008 09:56:09 -0300 (BRST) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org To: alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org Benjamin van den Hout escreveu: > Gustavo da Silva Serra wrote: > > >> I am developing an application that captures sound and send it >> through a network, just like a sound server. To test it I am using >> kaffeine with alsa output plugin. After some time playing continuously, >> or if I keep moving the position slider backward and forward, I get >> choppy sound. If I close and reopen the capture stream opened by my >> sound server, the sound is restored to good quality. Sometimes I have to >> reopen many times before I get a good sound. When I use kaffeine oss >> output plugin I don't have this issue. I don't have an audio sound card, >> so I don't know if this is an *aloop* issue. >> > > >> Here are some details: >> - RedHat EL 4 kernel 2.6.9.55-ELsmp 64bit >> - Alsa 1.0.16 >> - Xinelib 1.1.12 >> > > Hi all, > > I'm experiencing the same problem as Gustavo. In my case I have a SIP > client calling to another PC and I'm injecting audio with aplay (or > amarok, no difference there) into that SIP call. About 8/10 times > everything goes well, the other two times the audio that comes out at > the other PC sounds really choppy. Both PC's are on the same local > network so that is probably not the problem. > > What I found out is that if I patch aloop-kernel.c in the 'static > struct snd_pcm_hardware snd_card_loopback_info' to have ".formats = > (SNDRV_PCM_FMTBIT_S8 )," this problem goes away. But then I'm stuck > with 8 bit audio. It sounds a bit like the aloop device sometimes > doesn't properly synchronise the 16 bit (or 32bit, tried that as well) > samples on both PCM devices and things get mis-aligned. I'm quite new > to ALSA so please don't laugh too hard if I'm missing something here > :) > > Any input is greatly appreciated! > > Kind regards, > Benjamin van den Hout > _______________________________________________ > Alsa-devel mailing list > Alsa-devel@alsa-project.org > http://mailman.alsa-project.org/mailman/listinfo/alsa-devel > > __________ NOD32 3088 (20080509) Information __________ > > This message was checked by NOD32 antivirus system. > http://www.eset.com > > Well, I discovered that only xinelib has this problem. Xmms and alsaplayer, for example, don't have this issue. I am testing VLC and it seems to work fine. I am not surprised, since the xine source code that deals with alsa is huge and ugly, it must be very hard to mantain that.