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authorRobin Gareus <robin@gareus.org>2016-04-08 18:07:45 +0200
committerRobin Gareus <robin@gareus.org>2016-04-08 18:16:37 +0200
commit681b65aa0b68c9e7a686de2d6ca0c18c61cb444b (patch)
tree3c1d956bf968aa174b804f0d87d0460af95de4f8 /libs/ardour/fixed_delay.cc
parent743e6176df3e08408227ad5afb83accf4a6f4c1a (diff)
Add a fixed (not de-clicked) multi-buffer audio/midi delayline.
A ringbuffer intended to be used for plugin-thru/bypass latency compensation.
Diffstat (limited to 'libs/ardour/fixed_delay.cc')
-rw-r--r--libs/ardour/fixed_delay.cc132
1 files changed, 132 insertions, 0 deletions
diff --git a/libs/ardour/fixed_delay.cc b/libs/ardour/fixed_delay.cc
new file mode 100644
index 0000000000..d59619cdf9
--- /dev/null
+++ b/libs/ardour/fixed_delay.cc
@@ -0,0 +1,132 @@
+/*
+ * Copyright (C) 2016 Robin Gareus <robin@gareus.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "ardour/audio_buffer.h"
+#include "ardour/buffer_set.h"
+#include "ardour/fixed_delay.h"
+#include "ardour/midi_buffer.h"
+
+using namespace ARDOUR;
+
+FixedDelay::FixedDelay ()
+ : _max_delay (0)
+ , _delay (0)
+ , _pending_flush (false)
+{
+ for (size_t i = 0; i < DataType::num_types; ++i) {
+ _buffers.push_back (BufferVec ());
+ }
+ _count.reset ();
+}
+
+FixedDelay::~FixedDelay ()
+{
+ clear ();
+}
+
+void
+FixedDelay::configure (const ChanCount& count, framecnt_t max_delay)
+{
+ if (max_delay <= _max_delay || count <= _count) {
+ return;
+ }
+ _max_delay = std::max (_max_delay, max_delay);
+ for (DataType::iterator i = DataType::begin (); i != DataType::end (); ++i) {
+ ensure_buffers (*i, count.get (*i), _max_delay + 1);
+ }
+}
+
+void
+FixedDelay::set (const ChanCount& count, framecnt_t delay)
+{
+ configure (count, delay);
+ _delay = delay;
+}
+
+void
+FixedDelay::ensure_buffers (DataType type, size_t num_buffers, size_t buffer_capacity)
+{
+ assert (type != DataType::NIL);
+ assert (type < _buffers.size ());
+ if (num_buffers == 0) {
+ return;
+ }
+ BufferVec& bufs = _buffers[type];
+ if (bufs.size () < num_buffers || (bufs.size () > 0 && bufs[0]->buf->capacity () < buffer_capacity)) {
+ for (BufferVec::iterator i = bufs.begin (); i != bufs.end (); ++i) {
+ delete (*i);
+ }
+ bufs.clear ();
+ for (size_t i = 0; i < num_buffers; ++i) {
+ bufs.push_back (new DelayBuffer (type, buffer_capacity));
+ }
+ _count.set (type, num_buffers);
+ }
+}
+
+void
+FixedDelay::clear ()
+{
+ for (std::vector<BufferVec>::iterator i = _buffers.begin (); i != _buffers.end (); ++i) {
+ for (BufferVec::iterator j = (*i).begin (); j != (*i).end (); ++j) {
+ delete *j;
+ }
+ (*i).clear ();
+ }
+ _buffers.clear ();
+ _count.reset ();
+}
+
+void
+FixedDelay::delay (
+ ARDOUR::DataType dt, uint32_t id,
+ Buffer& out, const Buffer& in,
+ pframes_t n_frames,
+ framecnt_t dst_offset, framecnt_t src_offset)
+{
+ if (_delay == 0) {
+ out.read_from (in, n_frames, dst_offset, src_offset);
+ return;
+ }
+
+ assert (dt < _buffers.size ());
+ assert (id < _buffers[dt].size ());
+ DelayBuffer *db = _buffers[dt][id];
+
+ if (db->pos + n_frames > _max_delay) {
+ uint32_t w0 = _max_delay - db->pos;
+ uint32_t w1 = db->pos + n_frames - _max_delay;
+ db->buf->read_from (in, w0, db->pos, src_offset);
+ db->buf->read_from (in, w1, 0, src_offset + w0);
+ } else {
+ db->buf->read_from (in, n_frames, db->pos, src_offset);
+ }
+
+ uint32_t rp = (db->pos + _max_delay - _delay) % _max_delay;
+
+ if (rp + n_frames > _max_delay) {
+ uint32_t r0 = _max_delay - rp;
+ uint32_t r1 = rp + n_frames - _max_delay;
+ out.read_from (*db->buf, r0, dst_offset, rp);
+ out.read_from (*db->buf, r1, dst_offset + r0, 0);
+ } else {
+ out.read_from (*db->buf, n_frames, dst_offset, rp);
+ }
+
+ db->pos = (db->pos + n_frames) % _max_delay;
+}