AOSS, obsoleted? Not quite!

Fibonacci · #1 25th September 2006, 05:42 AM

Hello,

Ever since I installed FC5, I've had problems with sound from the Adobe Flash plugin, which probably most of you have already experienced - audio and video going out of sync after a while, not being able to play from any other audio source while Flash was playing, or viceversa, and so on.

Searching on the internet I learnt about ALSA, OSS, and the alsa-oss package, with which this audio problems would be solved automagically, by running aoss <offending program>. Sadly, the alsa-oss package was nowhere to be found within my YUM repos, and a search on the Fedoraforum revealed it had been "obsoleted", because OSS emulation was enabled by default.
Well, I tried some of the different /etc/asound.conf provided in the threads that mentiones OSS emulation, and though I enabled software mixing through dmix (which has a crappy quality, but is all I've got), I couldn't get the Flash sound issues solved - those were never even addressed!

After a whole day of dissappointment, I thought what the heck, I'm building alsa-oss from source. Sure enough, I went to ftp://ftp.alsa-project.org/pub/oss-lib/, downloaded the source tarball, compiled & installed it, ran aoss firefox, and Flash sound works like a charm! A/V sync works fine, and now I can play sound from multiple sources including Flash! (cue the music: Händel's HALLELUJAH).
Obsoleted? Not at all. alsa-oss should be put back in at least one of the standard repos, or even come by default with Fedora.

***bob*** · #2 25th September 2006, 01:32 PM

If you feel that there's a good reason to have it put back, why not communicate with the developers: http://fedoraproject.org/wiki/Commun...39580b12a902c5 Since they don't monitor our Forum, this isn't the right place to make the request.

RahulSundaram · #3 25th September 2006, 01:44 PM

Quote:

Originally Posted by Fibonacci

Hello,

Ever since I installed FC5, I've had problems with sound from the Adobe Flash plugin, which probably most of you have already experienced - audio and video going out of sync after a while, not being able to play from any other audio source while Flash was playing, or viceversa, and so on.

Searching on the internet I learnt about ALSA, OSS, and the alsa-oss package, with which this audio problems would be solved automagically, by running aoss <offending program>. Sadly, the alsa-oss package was nowhere to be found within my YUM repos, and a search on the Fedoraforum revealed it had been "obsoleted", because OSS emulation was enabled by default.
Well, I tried some of the different /etc/asound.conf provided in the threads that mentiones OSS emulation, and though I enabled software mixing through dmix (which has a crappy quality, but is all I've got), I couldn't get the Flash sound issues solved - those were never even addressed!

After a whole day of dissappointment, I thought what the heck, I'm building alsa-oss from source. Sure enough, I went to ftp://ftp.alsa-project.org/pub/oss-lib/, downloaded the source tarball, compiled & installed it, ran aoss firefox, and Flash sound works like a charm! A/V sync works fine, and now I can play sound from multiple sources including Flash! (cue the music: Händel's HALLELUJAH).
Obsoleted? Not at all. alsa-oss should be put back in at least one of the standard repos, or even come by default with Fedora.

aoss is ALSA - OSS compatability library which is different from Dmix which does sound mixing for applications that uses the ALSA API. So aoss is not obsolete for applications that use the old OSS sound API.

All of the applications that we provide in Fedora Core uses ALSA so there is not much incentive for aoss to be provided by default, however if you are interested you can package it in Fedora Extras - http://fedoraproject.org/wiki/Extras.

Note that the next version of Flash is expected to support ALSA.

http://blogs.adobe.com/penguin.swf/2...sa_issues.html

markkuk · #4 25th September 2006, 04:40 PM

Quote:

Originally Posted by RahulSundaram

All of the applications that we provide in Fedora Core uses ALSA

Firefox uses OSS:

Code:

$ dmesg | grep OSS
application firefox-bin uses obsolete OSS audio interface
application firefox-bin uses obsolete OSS audio interface

The Fedora kernel includes the OSS emulation modules:

Code:

# lsmod
(...)
snd_seq_oss            32705  0
snd_pcm_oss            40017  0

aoss is an user-space alternative to using the kernel snd_*_oss modules.

RahulSundaram · #5 25th September 2006, 04:49 PM

Quote:

Originally Posted by markkuk

Firefox uses OSS:

Code:

$ dmesg | grep OSS
application firefox-bin uses obsolete OSS audio interface
application firefox-bin uses obsolete OSS audio interface

The Fedora kernel includes the OSS emulation modules:

Code:

# lsmod
(...)
snd_seq_oss            32705  0
snd_pcm_oss            40017  0

aoss is an user-space alternative to using the kernel snd_*_oss modules.

Firefox CAN use the OSS API but it is clearly obsolete as the warning tells you. ALSA is the default for the kernel and OSS emulation is provided for compatibility reasons and ALSA developers consider this to be more robust than aoss. OSS API is scheduled for removal in the upstream kernel. If you want it for other reasons, just package it in Fedora Extras.

Fibonacci · #6 25th September 2006, 05:13 PM

If OSS emulation through ALSA is enabled by default, then
1- why OSS-using programs (if you don't want to count Firefox, try Skype) cannot play sound through the ALSA mixer without AOSS, but have no problem doing it with AOSS?
2- why does Flash A/V go out of sync after a while without AOSS, but does not with AOSS?

RahulSundaram · #7 25th September 2006, 05:18 PM

Quote:

Originally Posted by Fibonacci

If OSS emulation through ALSA is enabled by default, then
1- why OSS-using programs (if you don't want to count Firefox, try Skype) cannot play sound through the ALSA mixer without AOSS, but have no problem doing it with AOSS?
2- why does Flash A/V go out of sync after a while without AOSS, but does not with AOSS?

Both of these are proprietary applications, so there is no easy way to know what's happening. You should report these problems to the application developers. If there are any applications within Fedora Core and Fedora Extras, then file a bug report in http://bugzilla.redhat.com.

Fibonacci · #8 25th September 2006, 05:23 PM

Quote:

Originally Posted by RahulSundaram

Both of these are proprietary applications, so there is no easy way to know what's happening. You should report these problems to the application developers. If there are any applications within Fedora Core and Fedora Extras, then file a bug report in http://bugzilla.redhat.com.

They have been reported a hundred times. Read what Mike Melanson has to say about it:

Quote:

The A/V sync problem had to do with the way the OSS code interacted with the Flash core in a less than optimal manner.

It is solved when AOSS is used, and it is NOT solved when AOSS is not used (try it!). Therefore, AOSS is not obsolete.

RahulSundaram · #9 25th September 2006, 05:25 PM

Quote:

Originally Posted by Fibonacci

They have been reported a hundred times. Read what Mike Melanson has to say about it:

It is solved when AOSS is used, and it is NOT solved when AOSS is not used (try it!). Therefore, AOSS is not obsolete.

Where is it reported? Kindly provide a bugzilla report link for the cited issues.

Fibonacci · #10 25th September 2006, 05:29 PM

Quote:

Originally Posted by RahulSundaram

Where is it reported? Kindly provide a bugzilla report link for the cited issues.

I didn't know there was Bugzilla for Flash and for Skype. Would you please give me the web address?

RahulSundaram · #11 25th September 2006, 05:33 PM

Quote:

Originally Posted by Fibonacci

I didn't know there was Bugzilla for Flash and for Skype. Would you please give me the web address?

I dont know whether there are bugzilla's for the above packages. You should use whatever method is recommended by them to report it. I was not asking for bugzilla reports on these packages but Fedora.

If you want Fedora to include aoss, the specific problems with kernel OSS compatibility modules should be reported in http://bugzilla.redhat.com.

Fibonacci · #12 25th September 2006, 05:36 PM

Quote:

Originally Posted by RahulSundaram

I dont know whether there are bugzilla's for the above packages. You should use whatever method is recommended by them to report it.

No method is recommended by them to report bugs, so I chose to directly email the developers - as hundreds of other Linux users did, judging from posts in many other forums.

Quote:

Originally Posted by RahulSundaram

I was not asking for bugzilla reports on these packages but Fedora.

And I was talking about problems with those packages.

Quote:

Originally Posted by RahulSundaram

If you want Fedora to include aoss, the specific problems with kernel OSS compatibility modules should be reported in http://bugzilla.redhat.com.

Will do.

Fibonacci · #13 25th September 2006, 08:56 PM

Quote:

Usage of aoss is preferred over kernel-level OSS emulation because if you need use the PCM plugin layer, enabling the use of the Dmix Plugin or asym.

It's not just me, I found that on the page markkuk provided.

Fibonacci · #14 26th September 2006, 01:11 AM

I've posted this to fedora-devel-list:
http://www.redhat.com/archives/fedor.../msg00686.html

Edit:

Quote:

Originally Posted by RahulSundaram

If you want Fedora to include aoss, the specific problems with kernel OSS compatibility modules should be reported in http://bugzilla.redhat.com.

It has already been done: https://bugzilla.redhat.com/bugzilla....cgi?id=187706.

steve941 · #15 26th September 2006, 03:49 AM

ya know here's something to try with ALSA ..
i feel so retarded because its so easy .. i was another thread somewhere on this form
(in gnome panel)
System >> Preferences >> Sound
check: Enable Software Sound Mixing (ESD)
that got Flash plugin sounds working for me, so id say give it a shot