Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
Is 'libao' useful/desirable? [ANSWERED]
View unanswered posts
View posts from last 24 hours

 
Reply to topic    Gentoo Forums Forum Index Multimedia
View previous topic :: View next topic  
Author Message
dufeu
l33t
l33t


Joined: 30 Aug 2002
Posts: 924
Location: US-FL-EST

PostPosted: Sun Jul 22, 2012 12:40 am    Post subject: Is 'libao' useful/desirable? [ANSWERED] Reply with quote

I'm building/re-purposing an Intel Atom based system (netbook) from 3rd stage install and I want to be sure the USE flags I set are reasonable.

In this instance, I see the 'ao' USE flag is not part of the standard profile I selected:
Code:
default/linux/x86/10.0/desktop/kde *

As I read the description on xiph.org, libao takes a sound stream which a program wants to play and outputs it into a single format suitable for whatever your sound stack expects.

Do I understand libao's function correctly and is libao actually useful? I've been under the impression that software like 'pulseaudio' and 'phonon' already performed this type of function.

Edit: And the ANSWER is -

I appreciate the answers and they led me in the right direction for what I needed to know.

With the clue of 'sox', I was able to look with more insight at systems where I have 'libao' present. On these systems, it turns out that libao was called in at the behest of 'k3b' only. This is because of my policy to turn on nearly all k3b USE flags on these systems in order to be sure of handling just about any CD/DVD/CVD task that may come up.

Unless you purchase a USB 2.0 connected external CD/DVD/RW drive, k3b is completely pointless for all Atom based netbooks. Since Atoms are used virtually only in netbooks, 'libao' is not useful nor desired for any Atom based computer.

Based on my further reading, 'libao' is not really useful nor desired anywhere. i.e. Those packages that can make use of it all appear to have alternatives for accomplishing the same thing. The only real reason to include 'libao' for most people would appear to be as an alternative library if they're dissatisfied with the provided library a given package uses. At this point, I'll probably turn off USE='ao' on all my systems.

Thanks for the good answers!
_________________
People whom think M$ is mediocre, don't know the half of it.


Last edited by dufeu on Tue Jul 31, 2012 3:57 pm; edited 2 times in total
Back to top
View user's profile Send private message
VinzC
Watchman
Watchman


Joined: 17 Apr 2004
Posts: 5098
Location: Dark side of the mood

PostPosted: Mon Jul 23, 2012 12:46 pm    Post subject: Reply with quote

On my system only sox depends on libao, which has been included BTW. So I guess it's a question whether you need sox or not I guess?
_________________
Gentoo addict: tomorrow I quit, I promise!... Just one more emerge...
1739!
Back to top
View user's profile Send private message
khayyam
Watchman
Watchman


Joined: 07 Jun 2012
Posts: 6227
Location: Room 101

PostPosted: Tue Jul 24, 2012 4:14 pm    Post subject: Reply with quote

dufeu ...

the only pacakges, besides sox, I can think of that might use libao are media-sound/vorbis-tools if the ogg123 useflag is enabled, and media-sound/cmus which works perfectly fine without it.

So, its not widely used, but as VincZ said, it depends on what particular functionality you need.

best ... khay
Back to top
View user's profile Send private message
dufeu
l33t
l33t


Joined: 30 Aug 2002
Posts: 924
Location: US-FL-EST

PostPosted: Tue Jul 31, 2012 4:11 pm    Post subject: Reply with quote

Finally, I don't consider these kinds of questions/answers to be complete without context. To that end for the systems where I have 'libao' enabled, the following should make it clear where I might possibly use it:
Code:
# USE="-ao" emerge -pNDv @world

These are the packages that would be merged, in order:

Calculating dependencies... done!
[ebuild   R    ] net-misc/rdesktop-1.7.1  USE="alsa ipv6 libsamplerate -ao* -debug -oss -pcsc-lite" 0 kB
[ebuild   R    ] media-sound/sox-14.4.0  USE="alsa amr encode ffmpeg flac id3tag mad ogg openmp png pulseaudio sndfile wavpack -ao* -debug -ladspa -oss -static-libs -twolame" 0 kB

Total: 2 packages (2 reinstalls), Size of downloads: 0 kB

# equery d sox && equery d rdesktop
 * These packages depend on sox:
app-cdr/k3b-2.0.2-r3 (sox ? media-sound/sox)
 * These packages depend on rdesktop:
kde-base/krdc-4.8.4 (rdesktop ? net-misc/rdesktop)

For me, in other words, 'ao' is not really needed for anything anywhere.
_________________
People whom think M$ is mediocre, don't know the half of it.


Last edited by dufeu on Wed Aug 01, 2012 5:33 pm; edited 1 time in total
Back to top
View user's profile Send private message
VinzC
Watchman
Watchman


Joined: 17 Apr 2004
Posts: 5098
Location: Dark side of the mood

PostPosted: Tue Jul 31, 2012 5:49 pm    Post subject: Reply with quote

Thank you very much for your deep investigation, dufeu.
_________________
Gentoo addict: tomorrow I quit, I promise!... Just one more emerge...
1739!
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Multimedia All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum