--- /dev/null
+/*
+ Copyright (C) 2006, 2013 Paul Davis
+ Copyright (C) 2013, 2014 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.,
+ 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include <assert.h>
+#include <cmath>
+
+#include "pbd/compose.h"
+
+#include "ardour/debug.h"
+#include "ardour/audio_buffer.h"
+#include "ardour/midi_buffer.h"
+#include "ardour/buffer_set.h"
+#include "ardour/delayline.h"
+
+using namespace std;
+using namespace PBD;
+using namespace ARDOUR;
+
+DelayLine::DelayLine (Session& s, const std::string& name)
+ : Processor (s, string_compose ("latency-compensation-%1", name))
+ , _delay(0)
+ , _pending_delay(0)
+ , _bsiz(0)
+ , _pending_bsiz(0)
+ , _roff(0)
+ , _woff(0)
+ , _pending_flush(false)
+{
+}
+
+DelayLine::~DelayLine ()
+{
+}
+
+#define FADE_LEN (16)
+void
+DelayLine::run (BufferSet& bufs, framepos_t /* start_frame */, framepos_t /* end_frame */, pframes_t nsamples, bool)
+{
+ const uint32_t chn = _configured_output.n_audio();
+ pframes_t p0 = 0;
+ uint32_t c;
+
+ const frameoffset_t pending_delay = _pending_delay;
+ const frameoffset_t delay_diff = _delay - pending_delay;
+ const bool pending_flush = _pending_flush;
+ _pending_flush = false;
+
+ /* run() and set_delay() may be called in parallel by
+ * different threads.
+ * if a larger buffer is needed, it is allocated in
+ * set_delay(), here it is just swap'ed in place
+ */
+ if (_pending_bsiz) {
+ assert(_pending_bsiz >= _bsiz);
+
+ const size_t boff = _pending_bsiz - _bsiz;
+ if (_bsiz > 0) {
+ /* write offset is retained. copy existing data to new buffer */
+ frameoffset_t wl = _bsiz - _woff;
+ memcpy(_pending_buf.get(), _buf.get(), sizeof(Sample) * _woff * chn);
+ memcpy(_pending_buf.get() + (_pending_bsiz - wl) * chn, _buf.get() + _woff * chn, sizeof(Sample) * wl * chn);
+
+ /* new buffer is all zero by default, fade into the existing data copied above */
+ frameoffset_t wo = _pending_bsiz - wl;
+ for (pframes_t pos = 0; pos < FADE_LEN; ++pos) {
+ const gain_t gain = (gain_t)pos / (gain_t)FADE_LEN;
+ for (c = 0; c < _configured_input.n_audio(); ++c) {
+ _pending_buf.get()[ wo * chn + c ] *= gain;
+ wo = (wo + 1) % (_pending_bsiz + 1);
+ }
+ }
+
+ /* read-pointer will be moved and may up anywhere..
+ * copy current data for smooth fade-out below
+ */
+ frameoffset_t roold = _roff;
+ frameoffset_t ro = _roff;
+ if (ro > _woff) {
+ ro += boff;
+ }
+ ro += delay_diff;
+ if (ro < 0) {
+ ro -= (_pending_bsiz +1) * floor(ro / (float)(_pending_bsiz +1));
+ }
+ ro = ro % (_pending_bsiz + 1);
+ for (pframes_t pos = 0; pos < FADE_LEN; ++pos) {
+ for (c = 0; c < _configured_input.n_audio(); ++c) {
+ _pending_buf.get()[ ro * chn + c ] = _buf.get()[ roold * chn + c ];
+ ro = (ro + 1) % (_pending_bsiz + 1);
+ roold = (roold + 1) % (_bsiz + 1);
+ }
+ }
+ }
+
+ if (_roff > _woff) {
+ _roff += boff;
+ }
+
+ _buf = _pending_buf;
+ _bsiz = _pending_bsiz;
+ _pending_bsiz = 0;
+ }
+
+ /* there may be no buffer when delay == 0.
+ * we also need to check audio-channels in case all audio-channels
+ * were removed in which case no new buffer was allocated. */
+ Sample *buf = _buf.get();
+ if (buf && _configured_output.n_audio() > 0) {
+
+ assert (_bsiz >= pending_delay);
+ const framecnt_t rbs = _bsiz + 1;
+
+ if (pending_delay != _delay || pending_flush) {
+ const pframes_t fade_len = (nsamples >= FADE_LEN) ? FADE_LEN : nsamples / 2;
+
+ DEBUG_TRACE (DEBUG::LatencyCompensation,
+ string_compose ("Old %1 delay: %2 bufsiz: %3 offset-diff: %4 write-offset: %5 read-offset: %6\n",
+ name(), _delay, _bsiz, ((_woff - _roff + rbs) % rbs), _woff, _roff));
+
+ // fade out at old position
+ c = 0;
+ for (BufferSet::audio_iterator i = bufs.audio_begin(); i != bufs.audio_end(); ++i, ++c) {
+ Sample * const data = i->data();
+ for (pframes_t pos = 0; pos < fade_len; ++pos) {
+ const gain_t gain = (gain_t)(fade_len - pos) / (gain_t)fade_len;
+ buf[ _woff * chn + c ] = data[ pos ];
+ data[ pos ] = buf[ _roff * chn + c ] * gain;
+ _roff = (_roff + 1) % rbs;
+ _woff = (_woff + 1) % rbs;
+ }
+ }
+
+ if (pending_flush) {
+ DEBUG_TRACE (DEBUG::LatencyCompensation,
+ string_compose ("Flush buffer: %1\n", name()));
+ memset(buf, 0, _configured_output.n_audio() * rbs * sizeof (Sample));
+ }
+
+ // adjust read pointer
+ _roff += _delay - pending_delay;
+
+ if (_roff < 0) {
+ _roff -= rbs * floor(_roff / (float)rbs);
+ }
+ _roff = _roff % rbs;
+
+ // fade in at new position
+ c = 0;
+ for (BufferSet::audio_iterator i = bufs.audio_begin(); i != bufs.audio_end(); ++i, ++c) {
+ Sample * const data = i->data();
+ for (pframes_t pos = fade_len; pos < 2 * fade_len; ++pos) {
+ const gain_t gain = (gain_t)(pos - fade_len) / (gain_t)fade_len;
+ buf[ _woff * chn + c ] = data[ pos ];
+ data[ pos ] = buf[ _roff * chn + c ] * gain;
+ _roff = (_roff + 1) % rbs;
+ _woff = (_woff + 1) % rbs;
+ }
+ }
+ p0 = 2 * fade_len;
+
+ _delay = pending_delay;
+
+ DEBUG_TRACE (DEBUG::LatencyCompensation,
+ string_compose ("New %1 delay: %2 bufsiz: %3 offset-diff: %4 write-offset: %5 read-offset: %6\n",
+ name(), _delay, _bsiz, ((_woff - _roff + rbs) % rbs), _woff, _roff));
+ }
+
+ assert(_delay == ((_woff - _roff + rbs) % rbs));
+
+ c = 0;
+ for (BufferSet::audio_iterator i = bufs.audio_begin(); i != bufs.audio_end(); ++i, ++c) {
+ Sample * const data = i->data();
+ for (pframes_t pos = p0; pos < nsamples; ++pos) {
+ buf[ _woff * chn + c ] = data[ pos ];
+ data[ pos ] = buf[ _roff * chn + c ];
+ _roff = (_roff + 1) % rbs;
+ _woff = (_woff + 1) % rbs;
+ }
+ }
+ }
+
+ if (_midi_buf.get()) {
+ _delay = pending_delay;
+
+ for (BufferSet::midi_iterator i = bufs.midi_begin(); i != bufs.midi_end(); ++i) {
+ if (i != bufs.midi_begin()) { break; } // XXX only one buffer for now
+
+ MidiBuffer* dly = _midi_buf.get();
+ MidiBuffer& mb (*i);
+ if (pending_flush) {
+ dly->silence(nsamples);
+ }
+
+ // If the delay time changes, iterate over all events in the dly-buffer
+ // and adjust the time in-place. <= 0 becomes 0.
+ //
+ // iterate over all events in dly-buffer and subtract one cycle
+ // (nsamples) from the timestamp, bringing them closer to de-queue.
+ for (MidiBuffer::iterator m = dly->begin(); m != dly->end(); ++m) {
+ MidiBuffer::TimeType *t = m.timeptr();
+ if (*t > nsamples + delay_diff) {
+ *t -= nsamples + delay_diff;
+ } else {
+ *t = 0;
+ }
+ }
+
+ // delay events in current-buffer, in place.
+ for (MidiBuffer::iterator m = mb.begin(); m != mb.end(); ++m) {
+ MidiBuffer::TimeType *t = m.timeptr();
+ *t += _delay;
+ }
+
+ // move events from dly-buffer into current-buffer until nsamples
+ // and remove them from the dly-buffer
+ for (MidiBuffer::iterator m = dly->begin(); m != dly->end();) {
+ const Evoral::MIDIEvent<MidiBuffer::TimeType> ev (*m, false);
+ if (ev.time() >= nsamples) {
+ break;
+ }
+ mb.insert_event(ev);
+ m = dly->erase(m);
+ }
+
+ // move events after nsamples from current-buffer into dly-buffer
+ // and trim current-buffer after nsamples
+ for (MidiBuffer::iterator m = mb.begin(); m != mb.end();) {
+ const Evoral::MIDIEvent<MidiBuffer::TimeType> ev (*m, false);
+ if (ev.time() < nsamples) {
+ ++m;
+ continue;
+ }
+ dly->insert_event(ev);
+ m = mb.erase(m);
+ }
+ }
+ }
+
+ _delay = pending_delay;
+}
+
+void
+DelayLine::set_delay(framecnt_t signal_delay)
+{
+ if (signal_delay < 0) {
+ signal_delay = 0;
+ cerr << "WARNING: latency compensation is not possible.\n";
+ }
+
+ const framecnt_t rbs = signal_delay + 1;
+
+ DEBUG_TRACE (DEBUG::LatencyCompensation,
+ string_compose ("%1 set_delay to %2 samples for %3 channels\n",
+ name(), signal_delay, _configured_output.n_audio()));
+
+ if (signal_delay <= _bsiz) {
+ _pending_delay = signal_delay;
+ return;
+ }
+
+ if (_pending_bsiz) {
+ if (_pending_bsiz < signal_delay) {
+ cerr << "LatComp: buffer resize in progress. "<< name() << "pending: "<< _pending_bsiz <<" want: " << signal_delay <<"\n"; // XXX
+ } else {
+ _pending_delay = signal_delay;
+ }
+ return;
+ }
+
+ if (_configured_output.n_audio() > 0 ) {
+ _pending_buf.reset(new Sample[_configured_output.n_audio() * rbs]);
+ memset(_pending_buf.get(), 0, _configured_output.n_audio() * rbs * sizeof (Sample));
+ _pending_bsiz = signal_delay;
+ } else {
+ _pending_buf.reset();
+ _pending_bsiz = 0;
+ }
+
+ _pending_delay = signal_delay;
+
+ DEBUG_TRACE (DEBUG::LatencyCompensation,
+ string_compose ("allocated buffer for %1 of size %2\n",
+ name(), signal_delay));
+}
+
+bool
+DelayLine::can_support_io_configuration (const ChanCount& in, ChanCount& out)
+{
+ out = in;
+ return true;
+}
+
+bool
+DelayLine::configure_io (ChanCount in, ChanCount out)
+{
+ if (out != in) { // always 1:1
+ return false;
+ }
+
+ // TODO realloc buffers if channel count changes..
+ // TODO support multiple midi buffers
+
+ DEBUG_TRACE (DEBUG::LatencyCompensation,
+ string_compose ("configure IO: %1 Ain: %2 Aout: %3 Min: %4 Mout: %5\n",
+ name(), in.n_audio(), out.n_audio(), in.n_midi(), out.n_midi()));
+
+ if (in.n_midi() > 0 && !_midi_buf) {
+ _midi_buf.reset(new MidiBuffer(16384));
+ }
+
+ return Processor::configure_io (in, out);
+}
+
+void
+DelayLine::flush()
+{
+ _pending_flush = true;
+}
+
+XMLNode&
+DelayLine::state (bool full_state)
+{
+ XMLNode& node (Processor::state (full_state));
+ node.add_property("type", "delay");
+ return node;
+}
projects / ardour.git / blobdiff