add a record/broadcast input

so users do not have to use external programs like Audacity and BUTT
when using external mixers

7 files changed, 54 insertions, 10 deletions

diff --git a/src/engine/enginemaster.cpp b/src/engine/enginemaster.cpp
index 0c3375188d..0719939081 100644
--- a/src/engine/enginemaster.cpp
+++ b/src/engine/enginemaster.cpp
@@ -48,6 +48,7 @@ EngineMaster::EngineMaster(UserSettingsPointer pConfig,
     m_bBusOutputConnected[EngineChannel::LEFT] = false;
     m_bBusOutputConnected[EngineChannel::CENTER] = false;
     m_bBusOutputConnected[EngineChannel::RIGHT] = false;
+    m_bExternalRecordBroadcastInputConnected = false;
     m_pWorkerScheduler = new EngineWorkerScheduler(this);
     m_pWorkerScheduler->start(QThread::HighPriority);
 
@@ -379,6 +380,9 @@ void EngineMaster::process(const int iBufferSize) {
     bool boothEnabled = m_pBoothEnabled->get();
     bool headphoneEnabled = m_pHeadphoneEnabled->get();
 
+    // TODO: remove assumption of stereo buffer
+    const unsigned int kChannels = 2;
+    const unsigned int iFrames = iBufferSize / kChannels;
     unsigned int iSampleRate = static_cast<int>(m_pMasterSampleRate->get());
     if (m_pEngineEffectsManager) {
         m_pEngineEffectsManager->onCallbackStart();
@@ -424,7 +428,7 @@ void EngineMaster::process(const int iBufferSize) {
     double measuredRoundTripLatency = m_pRoundTripLatency->get();
     // iBufferSize / iSampleRate gives double Mixxx's processing latency because
     // there are 2 channels per buffer. FIXME when removing the assumption of stereo channels.
-    double processingLatency = (double)iBufferSize / iSampleRate / 2.0 * 1000.0;
+    double processingLatency = (double)iBufferSize / iSampleRate / kChannels * 1000.0;
     if (measuredRoundTripLatency == 0.0) {
         inputLatencyCompensation = processingLatency;
     } else {
@@ -657,7 +661,10 @@ void EngineMaster::process(const int iBufferSize) {
 
         // Submit master samples to the side chain to do broadcasting, recording,
         // etc. (cpu intensive non-realtime tasks)
-        if (m_pEngineSideChain != NULL) {
+        // If recording/broadcasting from a sound card input,
+        // SoundManager will send the input buffer from the sound card to m_pSidechain
+        // so skip sending a signal to m_pSidechain here.
+        if (m_pEngineSideChain != NULL && !m_bExternalRecordBroadcastInputConnected) {
             if (configuredTalkoverMixMode == TalkoverMixMode::DIRECT_MONITOR
                 && m_pNumMicsConfigured->get() > 0) {
                 // When using direct monitoring, the user hears the microphone inputs
@@ -674,9 +681,9 @@ void EngineMaster::process(const int iBufferSize) {
                                           m_pSidechain, 1.0,
                                           m_pTalkover, 1.0,
                                           iBufferSize);
-                m_pEngineSideChain->writeSamples(m_pSidechain, iBufferSize);
+                m_pEngineSideChain->writeSamples(m_pSidechain, iFrames);
             } else {
-                m_pEngineSideChain->writeSamples(m_pMaster, iBufferSize);
+                m_pEngineSideChain->writeSamples(m_pMaster, iFrames);
             }
         }
 
@@ -907,6 +914,9 @@ void EngineMaster::onInputConnected(AudioInput input) {
       case AudioInput::VINYLCONTROL:
           // We don't track enabled vinyl control inputs.
           break;
+      case AudioInput::RECORD_BROADCAST:
+          m_bExternalRecordBroadcastInputConnected = true;
+          break;
       default:
           break;
     }
@@ -923,6 +933,9 @@ void EngineMaster::onInputDisconnected(AudioInput input) {
       case AudioInput::VINYLCONTROL:
           // We don't track enabled vinyl control inputs.
           break;
+      case AudioInput::RECORD_BROADCAST:
+          m_bExternalRecordBroadcastInputConnected = false;
+          break;
       default:
           break;
     }
diff --git a/src/engine/enginemaster.h b/src/engine/enginemaster.h
index 3ed0b50345..7e0c654571 100644
--- a/src/engine/enginemaster.h
+++ b/src/engine/enginemaster.h
@@ -364,6 +364,7 @@ class EngineMaster : public QObject, public AudioSource {
     ControlObject* m_pHeadphoneEnabled;
 
     volatile bool m_bBusOutputConnected[3];
+    bool m_bExternalRecordBroadcastInputConnected;
 };
 
 #endif
diff --git a/src/engine/sidechain/enginesidechain.cpp b/src/engine/sidechain/enginesidechain.cpp
index 6081fd966b..f7f2fec5a4 100644
--- a/src/engine/sidechain/enginesidechain.cpp
+++ b/src/engine/sidechain/enginesidechain.cpp
@@ -75,11 +75,24 @@ void EngineSideChain::addSideChainWorker(SideChainWorker* pWorker) {
     m_workers.append(pWorker);
 }
 
-void EngineSideChain::writeSamples(const CSAMPLE* newBuffer, int buffer_size) {
+void EngineSideChain::receiveBuffer(AudioInput input,
+                                    const CSAMPLE* pBuffer,
+                                    unsigned int iFrames) {
+    if (input.getType() != AudioInput::RECORD_BROADCAST) {
+        qDebug() << "WARNING: AudioInput type is not RECORD_BROADCAST. Ignoring incoming buffer.";
+        return;
+    }
+    writeSamples(pBuffer, iFrames);
+}
+
+void EngineSideChain::writeSamples(const CSAMPLE* pBuffer, int iFrames) {
     Trace sidechain("EngineSideChain::writeSamples");
-    int samples_written = m_sampleFifo.write(newBuffer, buffer_size);
+    // TODO: remove assumption of stereo buffer
+    const int kChannels = 2;
+    const int iSamples = iFrames * kChannels;
+    int samples_written = m_sampleFifo.write(pBuffer, iSamples);
 
-    if (samples_written != buffer_size) {
+    if (samples_written != iFrames) {
         Counter("EngineSideChain::writeSamples buffer overrun").increment();
     }
 
diff --git a/src/engine/sidechain/enginesidechain.h b/src/engine/sidechain/enginesidechain.h
index 72904b3a94..8497c07d91 100644
--- a/src/engine/sidechain/enginesidechain.h
+++ b/src/engine/sidechain/enginesidechain.h
@@ -24,11 +24,12 @@
 
 #include "preferences/usersettings.h"
 #include "engine/sidechain/sidechainworker.h"
+#include "soundio/soundmanagerutil.h"
 #include "util/fifo.h"
 #include "util/mutex.h"
 #include "util/types.h"
 
-class EngineSideChain : public QThread {
+class EngineSideChain : public QThread, public AudioDestination {
     Q_OBJECT
   public:
     EngineSideChain(UserSettingsPointer pConfig);
@@ -37,13 +38,19 @@ class EngineSideChain : public QThread {
     // Not thread-safe, wait-free. Submit buffer of samples to the sidechain for
     // processing. Should only be called from a single writer thread (typically
     // the engine callback).
-    void writeSamples(const CSAMPLE* buffer, int buffer_size);
+    void writeSamples(const CSAMPLE* pBuffer, int iFrames);
+
+    // Thin wrapper around writeSamples that is used by SoundManager when receiving
+    // from a sound card input instead of the engine
+    void receiveBuffer(AudioInput input,
+                       const CSAMPLE* pBuffer,
+                       unsigned int iFrames) override;
 
     // Thread-safe, blocking.
     void addSideChainWorker(SideChainWorker* pWorker);
 
   private:
-    void run();
+    void run() override;
 
     UserSettingsPointer m_pConfig;
     // Indicates that the thread should exit.
diff --git a/src/soundio/soundmanager.cpp b/src/soundio/soundmanager.cpp
index ee000846de..51da1cd814 100644
--- a/src/soundio/soundmanager.cpp
+++ b/src/soundio/soundmanager.cpp
@@ -28,6 +28,7 @@
 #include "engine/enginebuffer.h"
 #include "engine/enginemaster.h"
 #include "engine/sidechain/enginenetworkstream.h"
+#include "engine/sidechain/enginesidechain.h"
 #include "soundio/sounddevice.h"
 #include "soundio/sounddevicenetwork.h"
 #include "soundio/sounddevicenotfound.h"
@@ -80,6 +81,9 @@ SoundManager::SoundManager(UserSettingsPointer pConfig,
     m_pNetworkStream = QSharedPointer<EngineNetworkStream>(
             new EngineNetworkStream(2, 0));
 
+    AudioInput recordInput = AudioInput(AudioPath::RECORD_BROADCAST, 0, 2);
+    registerInput(recordInput, pMaster->getSideChain());
+
     queryDevices();
 
     if (!m_config.readFromDisk()) {
diff --git a/src/soundio/soundmanagerutil.cpp b/src/soundio/soundmanagerutil.cpp
index 8abfe01fbe..e890aa6237 100644
--- a/src/soundio/soundmanagerutil.cpp
+++ b/src/soundio/soundmanagerutil.cpp
@@ -163,6 +163,8 @@ QString AudioPath::getStringFromType(AudioPathType type) {
         return QString::fromAscii("Bus");
     case DECK:
         return QString::fromAscii("Deck");
+    case RECORD_BROADCAST:
+        return QString::fromAscii("Record/Broadcast");
     case VINYLCONTROL:
         return QString::fromAscii("Vinyl Control");
     case MICROPHONE:
@@ -205,6 +207,8 @@ QString AudioPath::getTrStringFromType(AudioPathType type, unsigned char index)
     case DECK:
         return QString("%1 %2").arg(QObject::tr("Deck"),
                                     QString::number(index + 1));
+    case RECORD_BROADCAST:
+        return QObject::tr("Record/Broadcast");
     case VINYLCONTROL:
         return QString("%1 %2").arg(QObject::tr("Vinyl Control"),
                                     QString::number(index + 1));
@@ -446,6 +450,7 @@ QList<AudioPathType> AudioInput::getSupportedTypes() {
 #endif
     types.append(AUXILIARY);
     types.append(MICROPHONE);
+    types.append(RECORD_BROADCAST);
     return types;
 }
 
diff --git a/src/soundio/soundmanagerutil.h b/src/soundio/soundmanagerutil.h
index 5088d3e10c..c8676b0c84 100644
--- a/src/soundio/soundmanagerutil.h
+++ b/src/soundio/soundmanagerutil.h
@@ -60,6 +60,7 @@ public:
         HEADPHONES,
         BUS,
         DECK,
+        RECORD_BROADCAST,
         VINYLCONTROL,
         MICROPHONE,
         AUXILIARY,