[alsa-devel] What does snd_pcm_delay() actually return?

Lennart Poettering mznyfn at 0pointer.de
Thu Jun 12 23:00:06 CEST 2008

On Thu, 12.06.08 14:08, Takashi Iwai (tiwai at suse.de) wrote:

> AFAIK, the problem here is that the handling of hwptr isn't
> inconsistent in the pulse plugin.  The definition of hwptr is the
> point being played (or at least, the point where it was already
> processed).  So, it's fine that you take the network latency into
> account for calculation of hwptr like the pulse delay callback
> actually does.
> But, then, pointer callback also must contain the same latency.  If
> the hwptr with network latency doesn't work well, then delay callback
> shouldn't have the latency as well.

But we need the network latency in there, because it is necessary for
doing a/v synchronization. The network latency can be quite

The "hw_ptr/appl_ptr" is just too simple to cover the networked


Lennart Poettering                        Red Hat, Inc.
lennart [at] poettering [dot] net         ICQ# 11060553
http://0pointer.net/lennart/           GnuPG 0x1A015CC4

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