Re: Megalatency
Re: Megalatency
- Subject: Re: Megalatency
- From: email@hidden
- Date: Wed, 5 Jan 2005 13:38:53 -0500 (EST)
- Importance: Normal
> I ask because I was wondering about latency issues for playing movies
> with sound over Airport Express. The advice given on the Rogue Amoeba
> forums is "Adjust the synchronisation manually in VLC or MPlayer" and I
> was wondering whether this could perhaps be performed automatically if
> VLC or MPlayer paid proper attention to timestamps, i.e., the Audio
> Unit requesting slices for playback several seconds into the future.
I'll pass that along to the slipstream coder and see what he thinks.
> In my attempts to bring this up on the Rogue Amoeba website it
> transpired that Slipstream was not written as an Audio Unit which
> surprised me because it means, amongst other things, that it will not
> play nicely with other Rogue Amoeba software such as Detour.
I should probably say that i'm to blame for Detour's existence. I believe
that the decision was made to have it as an application to make
broadcasting audio to the airport express as simple as possible. Doing it
as an AudioUnit or a HAL plugin would have made it more complicated for
users simply wanting to send an app like realplayer or wmp to the AirPort
Express. they'd either have to have an AU host or use it in conjunction
with something like Detour(for a hal plugin).
> Paul from Rogue Amoeba has rather avoided the question on the forums
> (e.g., http://www.rogueamoeba.com/forum/ubb/Forum7/HTML/000003.html),
> so I thought I'd ask here whether it was possible in principle, both to
> write the wrapper and to get the latency anywhere near correctly
> handled.
I'm going to avoid that question too as i don't want to contradict Paul's
non-answer. ;)
but as far as the latency goes i belive that the airport express waits
until it's fairly large buffer is completely full before it starts
playback. so you end up waiting the 5 or so seconds for that to happen.
at least that was the last i had heard from the coder.
> Thanks for your replies!
> Hamish
>
> On Jan 5, 2005, at 17:02, Dan Nigrin wrote:
>
>> He wanted an AudioUnit....though to your point, I'm not sure why.
>> Perhaps he wanted to only stream wirelessly an specific submix in a
>> larger app...?
>>
>> Dan
>>
>> At 11:57 AM -0500 1/5/05, email@hidden wrote:
>>> i'm not sure why you would even need jack for this, if you've got an
>>> app
>>> that's producing audio you just have Slipstream select that app for
>>> broadcast.
>>>
>>> -rudy
>>>
>>>> I wonder if when Slipstream is available, that you could try to use
>>>> it together with JackOSX and it's AudioUnit - that might be a
>>>> workaround with no coding necessary...
>>>>
>>>> Dan
>>>>
>>>> At 2:35 PM +0000 1/5/05, Hamish Allan wrote:
>>>>> Hello people,
>>>>>
>>>>> A quick question: is it theoretically possible to write an Audio
>>>>> Unit to expose Apple's Airport Express as a system audio output
>>>>> device?
>>>>>
>>>>> The technology to stream audio to the APEx exists as JustePort
>>>>> (http://www.nanocrew.net/software/JustePort-latest.tar.gz), but
>>>>> nobody seems to be wrapping it in an audio unit. I had hoped that
>>>>> Slipstream from Rogue Amoeba would be taking that approach, but it
>>>>> seems not.
>>>>>
>>>>> I wonder, is there any technical reason why not? Certainly such a
>>>>> device would have an extremely large latency but it should be
>>>>> possible to determine this fairly accurately (based on ping times
>>>>> and size of remote buffer) and therefore request audio slices with a
>>>>> timestamp far enough into the future. Even if the latency were not
>>>>> accurate it would still surely be worth writing a wrapper so that
>>>>> other music players, etc., can use the APEx?
>>>>>
>>>>> Thank you for your opinions,
>>>>> Hamish
>>>>>
>
>
>
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Coreaudio-api mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden