Add option to disable volume control

src/engine/enginebase.cpp

@@ -36,7 +36,7 @@
 #include "settings/backendsettingspage.h"
 
 Engine::Base::Base()
-    : volume_(50),
+    : volume_(100),
       beginning_nanosec_(0),
       end_nanosec_(0),
       scope_(kScopeSize),
@@ -103,6 +103,8 @@ void Engine::Base::ReloadSettings() {
   output_ = s.value("output").toString();
   device_ = s.value("device");
 
+  volume_control_ = s.value("volume_control", true).toBool();
+
   buffer_duration_nanosec_ = s.value("bufferduration", 4000).toLongLong() * kNsecPerMsec;
   buffer_min_fill_ = s.value("bufferminfill", 33).toInt();
 

src/engine/enginebase.h

@@ -112,6 +112,7 @@ public:
 
   // Simple accessors
   EngineType type() const { return type_; }
+  bool volume_control() const { return volume_control_; }
   inline uint volume() const { return volume_; }
 
   bool is_fadeout_enabled() const { return fadeout_enabled_; }
@@ -153,7 +154,7 @@ signals:
   // Always use the state from event, because it's not guaranteed that immediate subsequent call to state() won't return a stale value.
   void StateChanged(Engine::State);
 
-protected:
+ protected:
 
   struct PluginDetails {
     QString name;
@@ -163,6 +164,7 @@ protected:
   typedef QList<PluginDetails> PluginDetailsList;
 
   EngineType type_;
+  bool volume_control_;
   uint volume_;
   quint64 beginning_nanosec_;
   qint64 end_nanosec_;

src/engine/gstengine.cpp

@@ -803,6 +803,7 @@ shared_ptr<GstEnginePipeline> GstEngine::CreatePipeline() {
 
   shared_ptr<GstEnginePipeline> ret(new GstEnginePipeline(this));
   ret->set_output_device(output_, device_);
+  ret->set_volume_control(volume_control_);
   ret->set_replaygain(rg_enabled_, rg_mode_, rg_preamp_, rg_compression_);
   ret->set_buffer_duration_nanosec(buffer_duration_nanosec_);
   ret->set_buffer_min_fill(buffer_min_fill_);

src/engine/gstengine.h

@@ -75,6 +75,7 @@ class GstEngine : public Engine::Base, public GstBufferConsumer {
   void Pause();
   void Unpause();
   void Seek(quint64 offset_nanosec);
+
  protected:
   void SetVolumeSW(uint percent);
 

src/engine/gstenginepipeline.cpp

@@ -53,8 +53,7 @@ const int GstEnginePipeline::kGstStateTimeoutNanosecs = 10000000;
 const int GstEnginePipeline::kFaderFudgeMsec = 2000;
 
 const int GstEnginePipeline::kEqBandCount = 10;
-const int GstEnginePipeline::kEqBandFrequencies[] = {
-    60, 170, 310, 600, 1000, 3000, 6000, 12000, 14000, 16000};
+const int GstEnginePipeline::kEqBandFrequencies[] = { 60, 170, 310, 600, 1000, 3000, 6000, 12000, 14000, 16000 };
 
 int GstEnginePipeline::sId = 1;
 GstElementDeleter *GstEnginePipeline::sElementDeleter = nullptr;
@@ -64,8 +63,9 @@ GstEnginePipeline::GstEnginePipeline(GstEngine *engine)
       engine_(engine),
       id_(sId++),
       valid_(false),
-      output_(""),
+      output_(QString()),
       device_(QVariant()),
+      volume_control_(true),
       eq_enabled_(false),
       eq_preamp_(0),
       stereo_balance_(0.0f),
@@ -118,6 +118,12 @@ void GstEnginePipeline::set_output_device(const QString &output, const QVariant
 
 }
 
+void GstEnginePipeline::set_volume_control(bool volume_control) {
+
+  volume_control_ = volume_control;
+
+}
+
 void GstEnginePipeline::set_replaygain(bool enabled, int mode, float preamp, bool compression) {
 
   rg_enabled_ = enabled;
@@ -239,14 +245,21 @@ bool GstEnginePipeline::InitAudioBin() {
   probe_sink = engine_->CreateElement("fakesink", audiobin_);
 
   audio_queue = engine_->CreateElement("queue", audiobin_);
-  equalizer_preamp_ = engine_->CreateElement("volume", audiobin_, false);
-  equalizer_ = engine_->CreateElement("equalizer-nbands", audiobin_, false);
-  audio_panorama_ = engine_->CreateElement("audiopanorama", audiobin_, false);
-  volume_ = engine_->CreateElement("volume", audiobin_);
   audioscale_ = engine_->CreateElement("audioresample", audiobin_);
   convert = engine_->CreateElement("audioconvert", audiobin_);
 
-  if (!queue_ || !audioconvert_ || !tee || !probe_queue || !probe_converter || !probe_sink || !audio_queue || !volume_ || !audioscale_ || !convert) {
+  if (engine_->volume_control()) {
+    volume_ = engine_->CreateElement("volume", audiobin_);
+  }
+
+  audio_panorama_ = engine_->CreateElement("audiopanorama", audiobin_, false);
+
+  if (eq_enabled_) {
+    equalizer_preamp_ = engine_->CreateElement("volume", audiobin_, false);
+    equalizer_ = engine_->CreateElement("equalizer-nbands", audiobin_, false);
+  }
+
+  if (!queue_ || !audioconvert_ || !tee || !probe_queue || !probe_converter || !probe_sink || !audio_queue || !audioscale_ || !convert) {
     gst_object_unref(GST_OBJECT(audiobin_));
     return false;
   }
@@ -348,8 +361,16 @@ bool GstEnginePipeline::InitAudioBin() {
   // Don't force 16 bit.
   gst_element_link(probe_queue, probe_converter);
 
-  if (engine_->IsEqualizerEnabled() && equalizer_ && equalizer_preamp_ && audio_panorama_) gst_element_link_many(audio_queue, equalizer_preamp_, equalizer_, audio_panorama_, volume_, audioscale_, convert, nullptr);
-  else gst_element_link_many(audio_queue, volume_, audioscale_, convert, nullptr);
+  if (eq_enabled_ && equalizer_ && equalizer_preamp_ && audio_panorama_) {
+    if (volume_)
+      gst_element_link_many(audio_queue, equalizer_preamp_, equalizer_, audio_panorama_, volume_, audioscale_, convert, nullptr);
+    else
+      gst_element_link_many(audio_queue, equalizer_preamp_, equalizer_, audio_panorama_, audioscale_, convert, nullptr);
+  }
+  else {
+    if (volume_) gst_element_link_many(audio_queue, volume_, audioscale_, convert, nullptr);
+    else gst_element_link_many(audio_queue, audioscale_, convert, nullptr);
+  }
 
   // Let the audio output of the tee autonegotiate the bit depth and format.
   GstCaps *caps = gst_caps_new_empty_simple("audio/x-raw");
@@ -993,16 +1014,19 @@ void GstEnginePipeline::UpdateStereoBalance() {
 }
 
 void GstEnginePipeline::SetVolume(int percent) {
+  if (!volume_) return;
   volume_percent_ = percent;
   UpdateVolume();
 }
 
 void GstEnginePipeline::SetVolumeModifier(qreal mod) {
+  if (!volume_) return;
   volume_modifier_ = mod;
   UpdateVolume();
 }
 
 void GstEnginePipeline::UpdateVolume() {
+  if (!volume_) return;
   float vol = double(volume_percent_) * 0.01 * volume_modifier_;
   g_object_set(G_OBJECT(volume_), "volume", vol, nullptr);
 }

src/engine/gstenginepipeline.h

@@ -68,6 +68,7 @@ class GstEnginePipeline : public QObject {
 
   // Call these setters before Init
   void set_output_device(const QString &sink, const QVariant &device);
+  void set_volume_control(bool volume_control);
   void set_replaygain(bool enabled, int mode, float preamp, bool compression);
   void set_buffer_duration_nanosec(qint64 duration_nanosec);
   void set_buffer_min_fill(int percent);
@@ -187,6 +188,7 @@ signals:
   bool valid_;
   QString output_;
   QVariant device_;
+  bool volume_control_;
 
   // Equalizer
   bool eq_enabled_;

src/engine/vlcengine.cpp

@@ -173,6 +173,7 @@ void VLCEngine::Seek(quint64 offset_nanosec) {
 
 void VLCEngine::SetVolumeSW(uint percent) {
   if (!Initialised()) return;
+  if (!volume_control_ && percent != 100) return;
   libvlc_audio_set_volume(player_, percent);
 }
 

src/engine/xineengine.cpp

@@ -393,6 +393,7 @@ void XineEngine::Seek(quint64 offset_nanosec) {
 void XineEngine::SetVolumeSW(uint vol) {
 
   if (!stream_) return;
+  if (!volume_control_ && vol != 100) return;
   xine_set_param(stream_, XINE_PARAM_AUDIO_AMP_LEVEL, static_cast<uint>(vol * preamp_));
 
 }