scratch team mailing list archive

[Derek O'Connell <doc@xxxxxxxxxxxxxxxxx>]

On 05/02/2010 15:58, Amos Blanton wrote:
> Thanks for working on this Derek. Myself and all the other Scratchers
> running Linux are very grateful to have benefited from your stubbornness! :)
>
> Your approach makes sense to me. One minor additional point in favor of a
> Gst plugin-- I would imagine that in future versions of PA the interface to
> gstreamer would figure prominently in testing / the QA process. They'd be
> more likely to invest resources to find / fix something that breaks the
> interface with gstreamer (and thereby breaks all the apps that depend on it)
> than something that just breaks Scratch. So I can imagine some benefit to
> being on that bandwagon.
>   

Agree. Just hoping if possible to get a working plugin that can be
packaged for Lucid. If I cannot get the current plug-in working within a
day or so then I will move swiftly on to GSt.

-D
 
> However - time and resources are scarce and precious! So it seems like
> trying to fix the PA plugin is the best approach. And who knows - maybe PA
> will get stable enough that they won't break the plugin again? One can
> dream...
>
> On Thu, Feb 4, 2010 at 8:27 PM, Derek O'Connell <doc@xxxxxxxxxxxxxxxxx>wrote:
>
>   
>> Hi all, I have been updating myself on PA issues. Last time I looked
>> (~December) Lennart Poettering had disappeared on holiday while quite a
>> few people were having problems on Karmic with the Simple_API (which I
>> use in the Scratch plug-in). The problem boils down to default latency
>> being ~2s, much too long for most app's, and not easily controlled via
>> Simple_API (my attempts failed at least). The volume meter set a low
>> latency in order to display the current sound level/s so that's why
>> things improved for other app's when it was running.
>>
>> The problems were created by an internal change to the PA API
>> (supposedly one single flag setting!) between 9.04 / 9.10 and the good
>> news is that it's impact is at least now recognised. There seems to be
>> some new suggestions about how to get around the problem, including a
>> patch to set latency via an env var. So tomorrow I will see how far I
>> can get with them. The bad news is there seems to be new problems
>> introduced by the version of PA to be used in Lucid. Fingers crossed
>> they get sorted soon.
>>
>> Re GStreamer, the hope was/is that a GSt based plugin for Scratch would
>> avoid these issues but thinking about it there is no guarantee since GSt
>> itself relies on plugin's to interface with whatever sound server is in
>> use. On Ubuntu that will still be PA out-of-the-box. PA can of course be
>> shut down and bypassed but the ideal solution is one that avoids forcing
>> what may be *novice* users from having to reconfigure their system just
>> to run Scratch (auto shutdown/start-up of PA is not an option for other
>> reasons). So it makes sense to me to concentrate on working around
>> current PA issues before considering GSt, although GSt is still
>> attractive for the other options it brings to the table, as well as
>> isolating Scratch from specific sounds systems, ie, more platform/distro
>> independence.
>>
>> Btw, I don't claim to be an expert on any of the above, more like too
>> stubborn to know when to give up ;-) So if anyone else has expertise/
>> info/ advice I'm happy to hear it.
>>
>> -D
>>
>>
>>
>>     
>
>