summaryrefslogtreecommitdiff
path: root/libs/ardour/disk_reader.cc
diff options
context:
space:
mode:
authorRobin Gareus <robin@gareus.org>2017-09-28 06:31:12 +0200
committerRobin Gareus <robin@gareus.org>2017-09-29 05:03:48 +0200
commit8139becb1898187729b0ea57f145302d4975bf3a (patch)
tree79638d87c587765784fe56eeb530ff792442e0c5 /libs/ardour/disk_reader.cc
parent8ff3b5ecf6bd2b7d69b8f154ba8d21eb4fe86304 (diff)
Ongoing work on latency compensation
The general goal is to align transport-sample to be the audible frame and use that as "anchor" for all processing. transport_sample cannot become negative (00:00:00:00 is the first audible frame). Internally transport pre-rolls (read-ahead) before the transport starts to move. This allows inputs and disk to prefill the pipeline. When starting to roll, the session counts down a global "remaning preroll" counter, which is the worst-latency from in-to-out. Each route in turn will start processing at its own output-latency. Route::process_output_buffers() - which does the actual processing incl disk i/o - begins by offsetting the "current sample" by the route's process-latency and decrements the offset for each latent processor. At the end of the function the output will be aligned and match transport-sample - downstream-playback-latency (if any). PS. This commit is a first step only: transport looping & vari-speed have not yet been implemented/updated.
Diffstat (limited to 'libs/ardour/disk_reader.cc')
-rw-r--r--libs/ardour/disk_reader.cc18
1 files changed, 13 insertions, 5 deletions
diff --git a/libs/ardour/disk_reader.cc b/libs/ardour/disk_reader.cc
index a9f403d40b..624a9ac17d 100644
--- a/libs/ardour/disk_reader.cc
+++ b/libs/ardour/disk_reader.cc
@@ -253,11 +253,17 @@ DiskReader::run (BufferSet& bufs, samplepos_t start_sample, samplepos_t end_samp
}
}
- if (speed == 0.0 && (ms == MonitoringDisk)) {
- /* stopped. Don't accidentally pass any data from disk
- * into our outputs (e.g. via interpolation)
- */
- bufs.silence (nframes, 0);
+ if (speed == 0.0) {
+ /* stopped. Don't accidentally pass any data from disk
+ * into our outputs (e.g. via interpolation)
+ * nor jump ahead playback_sample when not rolling
+ */
+ if (ms == MonitoringDisk) {
+ /* when monitoring disk, clear input data so far,
+ * everything before the disk processor is not relevant.
+ */
+ bufs.silence (nframes, 0);
+ }
return;
}
@@ -625,6 +631,8 @@ DiskReader::seek (samplepos_t sample, bool complete_refill)
ChannelList::iterator chan;
boost::shared_ptr<ChannelList> c = channels.reader();
+ //sample = std::max ((samplecnt_t)0, sample -_session.worst_output_latency ());
+
for (n = 0, chan = c->begin(); chan != c->end(); ++chan, ++n) {
(*chan)->buf->reset ();
}