From 78a9791b5850e48dfcaf7045f443a082f14f58da Mon Sep 17 00:00:00 2001 From: Robin Gareus Date: Fri, 4 Dec 2015 17:08:45 +0100 Subject: [PATCH] add interface for latency updates w/o restarting the backend This is useful for USB devices. Since there is a ringbuffer in the driver (common on ALSA but also other platforms) to align the USB stream with USB bus timing the latency can differ every time the device is re-opened. --- libs/ardour/ardour/audio_backend.h | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/libs/ardour/ardour/audio_backend.h b/libs/ardour/ardour/audio_backend.h index 0428c36b44..379eae9fd9 100644 --- a/libs/ardour/ardour/audio_backend.h +++ b/libs/ardour/ardour/audio_backend.h @@ -350,6 +350,11 @@ class LIBARDOUR_API AudioBackend : public PortEngine { */ virtual bool can_change_buffer_size_when_running () const = 0; + /** return true if the backend can measure and update + * systemic latencies without restart. + */ + virtual bool can_change_systemic_latency_when_running () const { return false; } + /* Set the hardware parameters. * * If called when the current state is stopped or paused, -- 2.30.2