add libardour code for going completely silent after a compile-time defined number...

diff --git a/libs/ardour/ardour/audioengine.h b/libs/ardour/ardour/audioengine.h
index 83df9a8760bc2648a28b2a3e280ef3ddf9751aa2..445d299f396a9e8d7a051ec479868b3bd60a87cb 100644 (file)
--- a/libs/ardour/ardour/audioengine.h
+++ b/libs/ardour/ardour/audioengine.h
@@ -232,6 +232,16 @@ class LIBARDOUR_API AudioEngine : public SessionHandlePtr, public PortManager
 
        LatencyMeasurement measuring_latency () const { return _measuring_latency; }
 
+       /* These two are used only in builds where SILENCE_AFTER_SECONDS was
+        * set. BecameSilent will be emitted when the audioengine goes silent.
+        * reset_silence_countdown() can be used to reset the silence
+        * countdown, whose duration will be reduced to half of its previous
+        * value.
+        */
+       
+       PBD::Signal0<void> BecameSilent;
+       void reset_silence_countdown ();
+       
   private:
        AudioEngine ();
 
@@ -293,6 +303,12 @@ class LIBARDOUR_API AudioEngine : public SessionHandlePtr, public PortManager
        BackendMap _backends;
        AudioBackendInfo* backend_discover (const std::string&);
        void drop_backend ();
+
+#ifdef SILENCE_AFTER
+       framecnt_t _silence_countdown;
+       uint32_t   _silence_hit_cnt;
+#endif 
+
 };
        
 } // namespace ARDOUR

diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index 6329b29ad27420a53b3b793028eae52d25e09a20..942b75fbefba19770894e7cfc4b8c0ee2b97714d 100644 (file)
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -559,7 +559,6 @@ class LIBARDOUR_API Session : public PBD::StatefulDestructible, public PBD::Scop
        bool   transport_stopped() const { return _transport_speed == 0.0f; }
        bool   transport_rolling() const { return _transport_speed != 0.0f; }
 
-       void set_silent (bool yn);
        bool silent () { return _silent; }
 
        TempoMap&       tempo_map()       { return *_tempo_map; }

diff --git a/libs/ardour/audioengine.cc b/libs/ardour/audioengine.cc
index 452403e48531cbc5550fc608b76491985b5a3f16..1f878474f602d85e46b979882835c7f36f629916 100644 (file)
--- a/libs/ardour/audioengine.cc
+++ b/libs/ardour/audioengine.cc
@@ -23,6 +23,7 @@
 #include <exception>
 #include <stdexcept>
 #include <sstream>
+#include <cmath>
 
 #include <glibmm/timer.h>
 #include <glibmm/pattern.h>
@@ -63,6 +64,10 @@ using namespace PBD;
 gint AudioEngine::m_meter_exit;
 AudioEngine* AudioEngine::_instance = 0;
 
+#ifdef SILENCE_AFTER
+#define SILENCE_AFTER_SECONDS 10
+#endif
+
 AudioEngine::AudioEngine ()
        : session_remove_pending (false)
        , session_removal_countdown (-1)
@@ -89,9 +94,14 @@ AudioEngine::AudioEngine ()
     , _hw_devicelist_update_thread(0)
     , _hw_devicelist_update_count(0)
     , _stop_hw_devicelist_processing(0)
+#ifdef SILENCE_AFTER_SECONDS
+       , _silence_countdown (0)
+       , _silence_hit_cnt (0)
+#endif
 {
        g_atomic_int_set (&m_meter_exit, 0);
-    start_hw_event_processing();
+       reset_silence_countdown ();
+       start_hw_event_processing();
        discover_backends ();
 }
 
@@ -148,6 +158,10 @@ AudioEngine::sample_rate_change (pframes_t nframes)
 
        SampleRateChanged (nframes); /* EMIT SIGNAL */
 
+#ifdef SILENCE_AFTER_SECONDS
+       _silence_countdown = nframes * SILENCE_AFTER_SECONDS;
+#endif
+       
        return 0;
 }
 
@@ -349,10 +363,31 @@ AudioEngine::process_callback (pframes_t nframes)
                last_monitor_check = next_processed_frames;
        }
 
+#ifdef SILENCE_AFTER_SECONDS
+
+       bool was_silent = (_silence_countdown == 0);
+       
+       if (_silence_countdown >= nframes) {
+               _silence_countdown -= nframes;
+       } else {
+               _silence_countdown = 0;
+       }
+
+       if (!was_silent && _silence_countdown == 0) {
+               _silence_hit_cnt++;
+               BecameSilent (); /* EMIT SIGNAL */
+       }
+
+       if (_silence_countdown == 0 || _session->silent()) {
+               PortManager::silence (nframes);
+       }
+       
+#else  
        if (_session->silent()) {
                PortManager::silence (nframes);
        }
-
+#endif
+       
        if (session_remove_pending && session_removal_countdown) {
 
                PortManager::fade_out (session_removal_gain, session_removal_gain_step, nframes);
@@ -375,6 +410,19 @@ AudioEngine::process_callback (pframes_t nframes)
        return 0;
 }
 
+void
+AudioEngine::reset_silence_countdown ()
+{
+#ifdef SILENCE_AFTER_SECONDS
+       double sr = 48000; /* default in case there is no backend */
+
+       sr = sample_rate();
+
+       _silence_countdown = max (60 * sr, /* 60 seconds */
+                                 sr * (SILENCE_AFTER_SECONDS / pow (2, _silence_hit_cnt)));
+
+#endif
+}
 
 void
 AudioEngine::launch_device_control_app()
@@ -1081,6 +1129,7 @@ AudioEngine::set_sample_rate (float sr)
        if (!_backend) {
                return -1;
        }
+
        return _backend->set_sample_rate  (sr);
 }