linuxaudio.org

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>>> The only difference non-jack would make is you need some function to

quoted text
>>> tell you roughly what audio time it is you can call from another thread.

>>

>> Does one use the system clock for that?

> I think frame time (a frame of samples) is meant here  ? That time is

> delivered in the jackd process callback.

>

>> Is it accurate enough?

> Depends on the system clock used, I presume.

> For best accuracy, you have to configure your kernel to support HPET

> (high precision event) timers

> and make ALSA use it as default.

the clock used for the system clock is less important than using a DLL

quoted text
> to "link" the audio clock and the system clock. this enables you to

> answer the question "if its time T on clock1, what time is it on

> clock2?"

>

> fons wrote the canonical paper on this for a Linux Audio conference a

> few years ago, and JACK contains a DLL for this purpose

> (jack_get_microseconds() will return a prediction of the current time

> according to the audio clock, based on the system clock and the DLL.

>

thanks, it's sounding increasing like I should be using jack for the time

being.
Iain
--20cf3010ed57b9fe1404b115fdc5

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>>> The only difference non-jack would make is you need some funct=

ion to

quoted text
>>> tell you roughly what audio time it is you can call from anoth=

er thread.

quoted text
>>

>> Does one use the system clock for that?

> I think frame time (a frame of samples) is meant here =A0? That time i=

s

quoted text
> delivered in the jackd process callback.

>

>> Is it accurate enough?

> Depends on the system clock used, I presume.

> For best accuracy, you have to configure your kernel to support HPET

> (high precision event) timers

> and make ALSA use it as default.

the clock used for the system clock is less=

 important than using a DLL

to "link" the audio clock and the system clock. this enables you =

to

answer the question "if its time T on clock1, what time is it on

clock2?"
fons wrote the canonical paper on this for a Linux Audio conference a

few years ago, and JACK contains a DLL for this purpose

(jack_get_microseconds() will return a prediction of the current time

according to the audio clock, based on the system clock and the DLL.thanks, it's sounding increasing like I s=

hould be using jack for the time being. Iain
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