diff options
| -rw-r--r-- | libs/ardour/amp.cc | 142 | ||||
| -rw-r--r-- | libs/ardour/ardour/amp.h | 5 | ||||
| -rw-r--r-- | libs/ardour/delivery.cc | 3 | ||||
| -rw-r--r-- | libs/ardour/internal_send.cc | 3 | ||||
| -rw-r--r-- | libs/ardour/monitor_processor.cc | 3 |
5 files changed, 72 insertions, 84 deletions
diff --git a/libs/ardour/amp.cc b/libs/ardour/amp.cc index d328c15457..cca465a0b4 100644 --- a/libs/ardour/amp.cc +++ b/libs/ardour/amp.cc @@ -41,6 +41,7 @@ Amp::Amp (Session& s) , _apply_gain(true) , _apply_gain_automation(false) , _current_gain(1.0) + , _current_automation_frame (INT64_MAX) , _gain_automation_buffer(0) { Evoral::Parameter p (GainAutomation); @@ -88,14 +89,23 @@ Amp::run (BufferSet& bufs, framepos_t /*start_frame*/, framepos_t /*end_frame*/, gain_t* gab = _gain_automation_buffer; assert (gab); + const float a = 62.78 / _session.nominal_frame_rate(); // 10 Hz LPF + float lpf = _current_gain; + for (BufferSet::audio_iterator i = bufs.audio_begin(); i != bufs.audio_end(); ++i) { Sample* const sp = i->data(); + lpf = _current_gain; for (pframes_t nx = 0; nx < nframes; ++nx) { - sp[nx] *= gab[nx]; + sp[nx] *= lpf; + lpf += a * (gab[nx] - lpf); } } - _current_gain = gab[nframes-1]; + if (lpf < 1e-10) { + _current_gain = 0; + } else { + _current_gain = lpf; + } } else { /* manual (scalar) gain */ @@ -103,8 +113,7 @@ Amp::run (BufferSet& bufs, framepos_t /*start_frame*/, framepos_t /*end_frame*/, if (_current_gain != dg) { - Amp::apply_gain (bufs, nframes, _current_gain, dg); - _current_gain = dg; + _current_gain = Amp::apply_gain (bufs, _session.nominal_frame_rate(), nframes, _current_gain, dg); } else if (_current_gain != 1.0f) { @@ -133,39 +142,34 @@ Amp::run (BufferSet& bufs, framepos_t /*start_frame*/, framepos_t /*end_frame*/, _active = _pending_active; } -void -Amp::apply_gain (BufferSet& bufs, framecnt_t nframes, gain_t initial, gain_t target) +gain_t +Amp::apply_gain (BufferSet& bufs, framecnt_t sample_rate, framecnt_t nframes, gain_t initial, gain_t target) { - /** Apply a (potentially) declicked gain to the buffers of @a bufs - */ + /** Apply a (potentially) declicked gain to the buffers of @a bufs */ + gain_t rv = target; if (nframes == 0 || bufs.count().n_total() == 0) { - return; + return initial; } // if we don't need to declick, defer to apply_simple_gain if (initial == target) { apply_simple_gain (bufs, nframes, target); - return; - } - - const framecnt_t declick = std::min ((framecnt_t) 128, nframes); - gain_t delta; - double fractional_shift = -1.0/declick; - double fractional_pos; - - if (target < initial) { - /* fade out: remove more and more of delta from initial */ - delta = -(initial - target); - } else { - /* fade in: add more and more of delta from initial */ - delta = target - initial; + return target; } /* MIDI Gain */ - for (BufferSet::midi_iterator i = bufs.midi_begin(); i != bufs.midi_end(); ++i) { + gain_t delta; + if (target < initial) { + /* fade out: remove more and more of delta from initial */ + delta = -(initial - target); + } else { + /* fade in: add more and more of delta from initial */ + delta = target - initial; + } + MidiBuffer& mb (*i); for (MidiBuffer::iterator m = mb.begin(); m != mb.end(); ++m) { @@ -180,35 +184,35 @@ Amp::apply_gain (BufferSet& bufs, framecnt_t nframes, gain_t initial, gain_t tar /* Audio Gain */ + /* Low pass filter coefficient: 1.0 - e^(-2.0 * π * f / 48000) f in Hz. + * for f << SR, approx a ~= 6.2 * f / SR; + */ + const float a = 62.78 / sample_rate; // 10 Hz LPF + for (BufferSet::audio_iterator i = bufs.audio_begin(); i != bufs.audio_end(); ++i) { Sample* const buffer = i->data(); + float lpf = initial; - fractional_pos = 1.0; - - for (pframes_t nx = 0; nx < declick; ++nx) { - buffer[nx] *= (initial + (delta * (0.5 + 0.5 * cos (M_PI * fractional_pos)))); - fractional_pos += fractional_shift; + for (pframes_t nx = 0; nx < nframes; ++nx) { + buffer[nx] *= lpf; + lpf += a * (target - lpf); } - - /* now ensure the rest of the buffer has the target value applied, if necessary. */ - - if (declick != nframes) { - - if (target == 0.0) { - memset (&buffer[declick], 0, sizeof (Sample) * (nframes - declick)); - } else if (target != 1.0) { - apply_gain_to_buffer (&buffer[declick], nframes - declick, target); - } + if (i == bufs.audio_begin()) { + rv = lpf; } } + // 1e-10 ~ 200dB, prevent denormals. + if (rv < 1e-10) return 0; + if (fabsf(rv - 1.0) < 1e-10) return 1.0; + return rv; } void Amp::declick (BufferSet& bufs, framecnt_t nframes, int dir) { - /* Almost exactly like ::apply_gain() but skips MIDI buffers and has fixed initial+target - values. - */ + /* Similar to ::apply_gain() but skips MIDI buffers + * and use cos() Sigmoid decay with fixed initial+target values. + */ if (nframes == 0 || bufs.count().n_total() == 0) { return; @@ -256,55 +260,36 @@ Amp::declick (BufferSet& bufs, framecnt_t nframes, int dir) } } -void -Amp::apply_gain (AudioBuffer& buf, framecnt_t nframes, gain_t initial, gain_t target) + +gain_t +Amp::apply_gain (AudioBuffer& buf, framecnt_t sample_rate, framecnt_t nframes, gain_t initial, gain_t target) { - /** Apply a (potentially) declicked gain to the contents of @a buf + /* Apply a (potentially) declicked gain to the contents of @a buf + * -- used by MonitorProcessor::run() */ if (nframes == 0) { - return; + return initial; } // if we don't need to declick, defer to apply_simple_gain if (initial == target) { apply_simple_gain (buf, nframes, target); - return; - } - - const framecnt_t declick = std::min ((framecnt_t) 128, nframes); - gain_t delta; - double fractional_shift = -1.0/declick; - double fractional_pos; - - if (target < initial) { - /* fade out: remove more and more of delta from initial */ - delta = -(initial - target); - } else { - /* fade in: add more and more of delta from initial */ - delta = target - initial; + return target; } - Sample* const buffer = buf.data(); + const float a = 62.78 / sample_rate; // 10 Hz LPF, see [other] Amp::apply_gain() above, - fractional_pos = 1.0; - - for (pframes_t nx = 0; nx < declick; ++nx) { - buffer[nx] *= (initial + (delta * (0.5 + 0.5 * cos (M_PI * fractional_pos)))); - fractional_pos += fractional_shift; + float lpf = initial; + for (pframes_t nx = 0; nx < nframes; ++nx) { + buffer[nx] *= lpf; + lpf += a * (target - lpf); } - /* now ensure the rest of the buffer has the target value applied, if necessary. */ - - if (declick != nframes) { - - if (target == 0.0) { - memset (&buffer[declick], 0, sizeof (Sample) * (nframes - declick)); - } else if (target != 1.0) { - apply_gain_to_buffer (&buffer[declick], nframes - declick, target); - } - } + if (lpf < 1e-10) return 0; + if (fabsf(lpf - 1.0) < 1e-10) return 1.0; + return lpf; } void @@ -452,8 +437,13 @@ Amp::setup_gain_automation (framepos_t start_frame, framepos_t end_frame, framec assert (_gain_automation_buffer); _apply_gain_automation = _gain_control->list()->curve().rt_safe_get_vector ( start_frame, end_frame, _gain_automation_buffer, nframes); + if (start_frame != _current_automation_frame) { + _current_gain = _gain_automation_buffer[0]; + } + _current_automation_frame = end_frame; } else { _apply_gain_automation = false; + _current_automation_frame = INT64_MAX; } } diff --git a/libs/ardour/ardour/amp.h b/libs/ardour/ardour/amp.h index 5408c86bff..5bfcf1d311 100644 --- a/libs/ardour/ardour/amp.h +++ b/libs/ardour/ardour/amp.h @@ -59,10 +59,10 @@ public: XMLNode& state (bool full); int set_state (const XMLNode&, int version); - static void apply_gain (BufferSet& bufs, framecnt_t nframes, gain_t initial, gain_t target); + static gain_t apply_gain (BufferSet& bufs, framecnt_t sample_rate, framecnt_t nframes, gain_t initial, gain_t target); static void apply_simple_gain(BufferSet& bufs, framecnt_t nframes, gain_t target); - static void apply_gain (AudioBuffer& buf, framecnt_t nframes, gain_t initial, gain_t target); + static gain_t apply_gain (AudioBuffer& buf, framecnt_t sample_rate, framecnt_t nframes, gain_t initial, gain_t target); static void apply_simple_gain(AudioBuffer& buf, framecnt_t nframes, gain_t target); static void declick (BufferSet& bufs, framecnt_t nframes, int dir); @@ -111,6 +111,7 @@ private: bool _apply_gain; bool _apply_gain_automation; float _current_gain; + framepos_t _current_automation_frame; boost::shared_ptr<GainControl> _gain_control; diff --git a/libs/ardour/delivery.cc b/libs/ardour/delivery.cc index f7d679d3ba..f16719888f 100644 --- a/libs/ardour/delivery.cc +++ b/libs/ardour/delivery.cc @@ -262,8 +262,7 @@ Delivery::run (BufferSet& bufs, framepos_t start_frame, framepos_t end_frame, pf if (tgain != _current_gain) { /* target gain has changed */ - Amp::apply_gain (bufs, nframes, _current_gain, tgain); - _current_gain = tgain; + _current_gain = Amp::apply_gain (bufs, _session.nominal_frame_rate(), nframes, _current_gain, tgain); } else if (tgain == 0.0) { diff --git a/libs/ardour/internal_send.cc b/libs/ardour/internal_send.cc index 33b299dfee..de5af0c6e2 100644 --- a/libs/ardour/internal_send.cc +++ b/libs/ardour/internal_send.cc @@ -194,8 +194,7 @@ InternalSend::run (BufferSet& bufs, framepos_t start_frame, framepos_t end_frame /* target gain has changed */ - Amp::apply_gain (mixbufs, nframes, _current_gain, tgain); - _current_gain = tgain; + _current_gain = Amp::apply_gain (mixbufs, _session.nominal_frame_rate(), nframes, _current_gain, tgain); } else if (tgain == 0.0) { diff --git a/libs/ardour/monitor_processor.cc b/libs/ardour/monitor_processor.cc index a88de86ec1..f19ce908ec 100644 --- a/libs/ardour/monitor_processor.cc +++ b/libs/ardour/monitor_processor.cc @@ -301,8 +301,7 @@ MonitorProcessor::run (BufferSet& bufs, framepos_t /*start_frame*/, framepos_t / if (target_gain != _channels[chn]->current_gain || target_gain != 1.0f) { - Amp::apply_gain (*b, nframes, _channels[chn]->current_gain, target_gain); - _channels[chn]->current_gain = target_gain; + _channels[chn]->current_gain = Amp::apply_gain (*b, _session.nominal_frame_rate(), nframes, _channels[chn]->current_gain, target_gain); } ++chn; |