Re: [Jack-Devel] JACK2 for Android newly released!

I have not had an opportunity to look at the new release, but I did attend
the presentation at the San Francisco developers conference in October
2013. I have released an app based on their JACK-based pro audio framework.
I believe it was the first 3rd party app. (
https://play.google.com/store/apps/details?id=com.blueverdi.myruckus) .

At the developers conference Samsung stated the pro audio framework was
supported only on Note 3 and Galaxy Tab 10.1 2014. My experience is on Note
3.

First, the framework only supported I/O via built-in audio devices. No USB.
This means audio quality is compromised by their audio hardware.
Importantly, they are restricted to 48k/16 bit.

Second, per their conference presentation they are running with two 512
sample buffers. At 48k this misses the mark for low latency. Even at that
level of latency I saw significant xruns. Using only their example simple
client - which generates a stereo sine wave from a table -  I heard
numerous audio artifacts. Logcat output showed 29 xruns in a two minute
test. This was completely reproducible. I reported this on their developer
forum on Jan 2 and as of today there has been no Samsung response.

In the interests of full disclosure I have ported JACK to Android myself.
The  project is on hold due to the Samsung release, in spite of better
performance.



On Fri, Jan 24, 2014 at 7:08 AM, 김정연 <[hidden]> wrote:

> > Does that mean JACK2 will already come installed on upcoming Samsung
> devices?
> Yes.
>
> >
> > What about low latency/RT stabilty, have you tested running JACK2 with
> low
> > latency period settings (i.e. <= 5ms) on Android? Does it run quite
> stable
> > without xruns?
> Well, it is hard to say, latency depends on platform limitation or hw spec.
> for example, android's fast mixer introduces 10ms of latency.
> http://source.android.com/devices/latency_design.html
>
> Generally, mobile devices do control power consumption much sensitive
> than PC, of course this limitation may possible occur XRUNS in some
> scenarios.
> We always think how to improve performance better, *** so I need
> expert's advice here. ***
> But, modern mobile devices increase number of cores(quad-core or
> more...), so I guess JACK2 works better performance along with number
> of cores. Of course, it works stable if allows reasonable clock-speed
> and cores.
>
> Thanks,
> KimJeongYeon
> 
> Jack-Devel mailing list
> [hidden]
> http://lists.jackaudio.org/listinfo.cgi/jack-devel-jackaudio.org
>

1390581659.4364_0.ltw:2,a <CALNZyLF6ZVWyZ05=is=J_P+XTBub6FGcbzZGSpWDH3OC38wuHg at mail dot gmail dot com>