Retrieve channel configuration on macOS

iOS needs some more work.

Change-Id: I11048cce5d3da8a7b6e2477a2453cfac43f75231
Reviewed-by: Rafael Roquetto <rafael.roquetto@qt.io>

6 files changed, 196 insertions, 15 deletions

diff --git a/src/multimedia/audio/qaudioformat.h b/src/multimedia/audio/qaudioformat.h
index 03e312247..b4cbb6428 100644
--- a/src/multimedia/audio/qaudioformat.h
+++ b/src/multimedia/audio/qaudioformat.h
@@ -97,6 +97,7 @@ public:
         BottomFrontLeft,
         BottomFrontRight
     };
+    static constexpr int NChannelPositions = BottomFrontRight + 1;
 
     enum ChannelConfig : quint32 {
         ChannelConfigUnknown = 0,
diff --git a/src/multimedia/darwin/qcoreaudioutils.mm b/src/multimedia/darwin/qcoreaudioutils.mm
index 8faa353c7..c8ee541cf 100644
--- a/src/multimedia/darwin/qcoreaudioutils.mm
+++ b/src/multimedia/darwin/qcoreaudioutils.mm
@@ -38,6 +38,7 @@
 ****************************************************************************/
 
 #include "qcoreaudioutils_p.h"
+#include <qdebug.h>
 #include <mach/mach_time.h>
 
 QT_BEGIN_NAMESPACE
@@ -134,6 +135,156 @@ AudioStreamBasicDescription CoreAudioUtils::toAudioStreamBasicDescription(QAudio
     return sf;
 }
 
+
+static constexpr struct {
+    QAudioFormat::AudioChannelPosition pos;
+    AudioChannelLabel label;
+} channelMap[] =  {
+        { QAudioFormat::FrontLeft, kAudioChannelLabel_Left },
+        { QAudioFormat::FrontRight, kAudioChannelLabel_Right },
+        { QAudioFormat::FrontCenter, kAudioChannelLabel_Center },
+        { QAudioFormat::LFE, kAudioChannelLabel_LFEScreen },
+        { QAudioFormat::BackLeft, kAudioChannelLabel_LeftSurround },
+        { QAudioFormat::BackRight, kAudioChannelLabel_RightSurround },
+        { QAudioFormat::FrontLeftOfCenter, kAudioChannelLabel_LeftCenter },
+        { QAudioFormat::FrontRightOfCenter, kAudioChannelLabel_RightCenter },
+        { QAudioFormat::BackCenter, kAudioChannelLabel_CenterSurround },
+        { QAudioFormat::LFE2, kAudioChannelLabel_LFE2 },
+        { QAudioFormat::SideLeft, kAudioChannelLabel_LeftSurroundDirect }, // ???
+        { QAudioFormat::SideRight, kAudioChannelLabel_RightSurroundDirect }, // ???
+        { QAudioFormat::TopFrontLeft, kAudioChannelLabel_VerticalHeightLeft },
+        { QAudioFormat::TopFrontRight, kAudioChannelLabel_VerticalHeightRight },
+        { QAudioFormat::TopFrontCenter, kAudioChannelLabel_VerticalHeightCenter },
+        { QAudioFormat::TopCenter, kAudioChannelLabel_CenterTopMiddle },
+        { QAudioFormat::TopBackLeft, kAudioChannelLabel_TopBackLeft },
+        { QAudioFormat::TopBackRight, kAudioChannelLabel_TopBackRight },
+        { QAudioFormat::TopSideLeft, kAudioChannelLabel_LeftTopMiddle },
+        { QAudioFormat::TopSideRight, kAudioChannelLabel_RightTopMiddle },
+        { QAudioFormat::TopBackCenter, kAudioChannelLabel_TopBackCenter },
+};
+
+std::unique_ptr<AudioChannelLayout> CoreAudioUtils::toAudioChannelLayout(const QAudioFormat &format, UInt32 *size)
+{
+    auto channelConfig = format.channelConfig();
+    if (channelConfig == QAudioFormat::ChannelConfigUnknown)
+        channelConfig = QAudioFormat::defaultChannelConfigForChannelCount(format.channelCount());
+
+    *size = sizeof(AudioChannelLayout) + int(QAudioFormat::NChannelPositions)*sizeof(AudioChannelDescription);
+    auto *layout = static_cast<AudioChannelLayout *>(malloc(*size));
+    memset(layout, 0, *size);
+    layout->mChannelLayoutTag = kAudioChannelLayoutTag_UseChannelDescriptions;
+
+    for (const auto &m : channelMap) {
+        if (channelConfig & QAudioFormat::channelConfig(m.pos))
+            layout->mChannelDescriptions[layout->mNumberChannelDescriptions++].mChannelLabel = m.label;
+    }
+
+    if (channelConfig & QAudioFormat::channelConfig(QAudioFormat::BottomFrontCenter)) {
+        auto &desc = layout->mChannelDescriptions[layout->mNumberChannelDescriptions++];
+        desc.mChannelLabel = kAudioChannelLabel_UseCoordinates;
+        desc.mChannelFlags = kAudioChannelFlags_SphericalCoordinates;
+        desc.mCoordinates[kAudioChannelCoordinates_Azimuth] = 0.f;
+        desc.mCoordinates[kAudioChannelCoordinates_Elevation] = -20.;
+        desc.mCoordinates[kAudioChannelCoordinates_Distance] = 1.f;
+    }
+    if (channelConfig & QAudioFormat::channelConfig(QAudioFormat::BottomFrontLeft)) {
+        auto &desc = layout->mChannelDescriptions[layout->mNumberChannelDescriptions++];
+        desc.mChannelLabel = kAudioChannelLabel_UseCoordinates;
+        desc.mChannelFlags = kAudioChannelFlags_SphericalCoordinates;
+        desc.mCoordinates[kAudioChannelCoordinates_Azimuth] = -45.f;
+        desc.mCoordinates[kAudioChannelCoordinates_Elevation] = -20.;
+        desc.mCoordinates[kAudioChannelCoordinates_Distance] = 1.f;
+    }
+    if (channelConfig & QAudioFormat::channelConfig(QAudioFormat::BottomFrontRight)) {
+        auto &desc = layout->mChannelDescriptions[layout->mNumberChannelDescriptions++];
+        desc.mChannelLabel = kAudioChannelLabel_UseCoordinates;
+        desc.mChannelFlags = kAudioChannelFlags_SphericalCoordinates;
+        desc.mCoordinates[kAudioChannelCoordinates_Azimuth] = 45.f;
+        desc.mCoordinates[kAudioChannelCoordinates_Elevation] = -20.;
+        desc.mCoordinates[kAudioChannelCoordinates_Distance] = 1.f;
+    }
+
+    return std::unique_ptr<AudioChannelLayout>(layout);
+}
+
+static constexpr struct {
+    AudioChannelLayoutTag tag;
+    QAudioFormat::ChannelConfig channelConfig;
+} layoutTagMap[] = {
+    { kAudioChannelLayoutTag_Mono, QAudioFormat::ChannelConfigMono },
+    { kAudioChannelLayoutTag_Stereo, QAudioFormat::ChannelConfigStereo },
+    { kAudioChannelLayoutTag_StereoHeadphones, QAudioFormat::ChannelConfigStereo },
+    { kAudioChannelLayoutTag_MPEG_1_0, QAudioFormat::ChannelConfigMono },
+    { kAudioChannelLayoutTag_MPEG_2_0, QAudioFormat::ChannelConfigStereo },
+    { kAudioChannelLayoutTag_MPEG_3_0_A, QAudioFormat::channelConfig(QAudioFormat::FrontLeft,
+                                                                     QAudioFormat::FrontRight,
+                                                                     QAudioFormat::FrontCenter) },
+    { kAudioChannelLayoutTag_MPEG_4_0_A, QAudioFormat::channelConfig(QAudioFormat::FrontLeft,
+                                                                     QAudioFormat::FrontRight,
+                                                                     QAudioFormat::FrontCenter,
+                                                                     QAudioFormat::BackCenter) },
+    { kAudioChannelLayoutTag_MPEG_5_0_A, QAudioFormat::ChannelConfigSurround5Dot0 },
+    { kAudioChannelLayoutTag_MPEG_5_1_A, QAudioFormat::ChannelConfigSurround5Dot1 },
+    { kAudioChannelLayoutTag_MPEG_6_1_A, QAudioFormat::channelConfig(QAudioFormat::FrontLeft,
+                                                                     QAudioFormat::FrontRight,
+                                                                     QAudioFormat::FrontCenter,
+                                                                     QAudioFormat::LFE,
+                                                                     QAudioFormat::BackLeft,
+                                                                     QAudioFormat::BackRight,
+                                                                     QAudioFormat::BackCenter) },
+    { kAudioChannelLayoutTag_MPEG_7_1_A, QAudioFormat::ChannelConfigSurround7Dot1 },
+    { kAudioChannelLayoutTag_SMPTE_DTV, QAudioFormat::channelConfig(QAudioFormat::FrontLeft,
+                                                                    QAudioFormat::FrontRight,
+                                                                    QAudioFormat::FrontCenter,
+                                                                    QAudioFormat::LFE,
+                                                                    QAudioFormat::BackLeft,
+                                                                    QAudioFormat::BackRight,
+                                                                    QAudioFormat::TopFrontLeft,
+                                                                    QAudioFormat::TopFrontRight) },
+
+    { kAudioChannelLayoutTag_ITU_2_1, QAudioFormat::ChannelConfig2Dot1 },
+    { kAudioChannelLayoutTag_ITU_2_2, QAudioFormat::channelConfig(QAudioFormat::FrontLeft,
+                                                                  QAudioFormat::FrontRight,
+                                                                  QAudioFormat::BackLeft,
+                                                                  QAudioFormat::BackRight) }
+};
+
+
+QAudioFormat::ChannelConfig CoreAudioUtils::fromAudioChannelLayout(const AudioChannelLayout *layout)
+{
+    for (const auto &m : layoutTagMap) {
+        if (m.tag == layout->mChannelLayoutTag)
+            return m.channelConfig;
+    }
+
+    quint32 channels = 0;
+    if (layout->mChannelLayoutTag == kAudioChannelLayoutTag_UseChannelDescriptions) {
+        // special case 1 and 2 channel configs, as they are often reported without proper descriptions
+        if (layout->mNumberChannelDescriptions == 1 && layout->mChannelDescriptions[0].mChannelLabel == kAudioChannelLabel_Unknown)
+            return QAudioFormat::ChannelConfigMono;
+        if (layout->mNumberChannelDescriptions == 2 &&
+            layout->mChannelDescriptions[0].mChannelLabel == kAudioChannelLabel_Unknown &&
+            layout->mChannelDescriptions[1].mChannelLabel == kAudioChannelLabel_Unknown)
+            return QAudioFormat::ChannelConfigStereo;
+
+        for (uint i = 0; i < layout->mNumberChannelDescriptions; ++i) {
+            bool found = false;
+            for (const auto &m : channelMap) {
+                if (layout->mChannelDescriptions[i].mChannelLabel == m.label) {
+                    channels |= QAudioFormat::channelConfig(m.pos);
+                    found = true;
+                    break;
+                }
+            }
+            if (!found)
+                qWarning() << "audio device has unknown channel" << layout->mChannelDescriptions[i].mChannelLabel;
+        }
+    } else {
+        qWarning() << "Channel layout uses unimplemented format";
+    }
+    return QAudioFormat::ChannelConfig(channels);
+}
+
 // QAudioRingBuffer
 CoreAudioRingBuffer::CoreAudioRingBuffer(int bufferSize):
     m_bufferSize(bufferSize)
diff --git a/src/multimedia/darwin/qcoreaudioutils_p.h b/src/multimedia/darwin/qcoreaudioutils_p.h
index 9fce95b52..b6730c978 100644
--- a/src/multimedia/darwin/qcoreaudioutils_p.h
+++ b/src/multimedia/darwin/qcoreaudioutils_p.h
@@ -66,6 +66,10 @@ public:
     static Q_MULTIMEDIA_EXPORT QAudioFormat toQAudioFormat(const AudioStreamBasicDescription& streamFormat);
     static AudioStreamBasicDescription toAudioStreamBasicDescription(QAudioFormat const& audioFormat);
 
+    // ownership is transferred to caller, free with ::free()
+    static std::unique_ptr<AudioChannelLayout> toAudioChannelLayout(const QAudioFormat &format, UInt32 *size);
+    static QAudioFormat::ChannelConfig fromAudioChannelLayout(const AudioChannelLayout *layout);
+
 private:
     static void initialize();
     static double sFrequency;
diff --git a/src/multimedia/darwin/qdarwinaudiodevice.mm b/src/multimedia/darwin/qdarwinaudiodevice.mm
index 8fe6f1a2c..e23c087f8 100644
--- a/src/multimedia/darwin/qdarwinaudiodevice.mm
+++ b/src/multimedia/darwin/qdarwinaudiodevice.mm
@@ -53,22 +53,24 @@
 QT_BEGIN_NAMESPACE
 
 #if defined(Q_OS_MACOS)
-    QCoreAudioDeviceInfo::QCoreAudioDeviceInfo(AudioDeviceID id, const QByteArray &device, QAudioDevice::Mode mode)
-        : QAudioDevicePrivate(device, mode),
-        m_deviceId(id)
+QCoreAudioDeviceInfo::QCoreAudioDeviceInfo(AudioDeviceID id, const QByteArray &device, QAudioDevice::Mode mode)
+    : QAudioDevicePrivate(device, mode),
+    m_deviceId(id)
 #else
-    QCoreAudioDeviceInfo::QCoreAudioDeviceInfo(const QByteArray &device, QAudioDevice::Mode mode)
-        : QAudioDevicePrivate(device, mode)
+QCoreAudioDeviceInfo::QCoreAudioDeviceInfo(const QByteArray &device, QAudioDevice::Mode mode)
+    : QAudioDevicePrivate(device, mode)
 #endif
-    {
-        preferredFormat = determinePreferredFormat();
-        description = getDescription();
-        minimumSampleRate = 1;
-        maximumSampleRate = 96000;
-        minimumChannelCount = 1;
-        maximumChannelCount = 16;
-        supportedSampleFormats << QAudioFormat::UInt8 << QAudioFormat::Int16 << QAudioFormat::Int32 << QAudioFormat::Float;
-    }
+{
+    description = getDescription();
+    getChannelLayout();
+    preferredFormat = determinePreferredFormat();
+    minimumSampleRate = 1;
+    maximumSampleRate = 96000;
+    minimumChannelCount = 1;
+    maximumChannelCount = 16;
+    supportedSampleFormats << QAudioFormat::UInt8 << QAudioFormat::Int16 << QAudioFormat::Int32 << QAudioFormat::Float;
+
+}
 
 
 QAudioFormat QCoreAudioDeviceInfo::determinePreferredFormat() const
@@ -121,6 +123,7 @@ QAudioFormat QCoreAudioDeviceInfo::determinePreferredFormat() const
         format.setSampleFormat(QAudioFormat::Int16);
         format.setChannelCount(mode == QAudioDevice::Input ? 1 : 2);
     }
+    format.setChannelConfig(channelConfiguration);
 
     return format;
 }
@@ -150,4 +153,23 @@ QString QCoreAudioDeviceInfo::getDescription() const
 #endif
 }
 
+void QCoreAudioDeviceInfo::getChannelLayout()
+{
+#ifdef Q_OS_MACOS
+    AudioObjectPropertyAddress audioDeviceChannelLayoutPropertyAddress = { kAudioDevicePropertyPreferredChannelLayout,
+                                                                    (mode == QAudioDevice::Input ? kAudioDevicePropertyScopeInput : kAudioDevicePropertyScopeOutput),
+                                                                    kAudioObjectPropertyElementMaster };
+    UInt32 propSize;
+    if (AudioObjectGetPropertyDataSize(m_deviceId, &audioDeviceChannelLayoutPropertyAddress, 0, nullptr, &propSize) == noErr) {
+        AudioChannelLayout *layout = static_cast<AudioChannelLayout *>(malloc(propSize));
+        if (AudioObjectGetPropertyData(m_deviceId, &audioDeviceChannelLayoutPropertyAddress, 0, nullptr, &propSize, layout) == noErr) {
+            channelConfiguration = CoreAudioUtils::fromAudioChannelLayout(layout);
+        }
+        free(layout);
+    }
+#else
+    channelConfiguration = (mode == QAudioDevice::Input) ? QAudioFormat::ChannelConfigMono : QAudioFormat::ChannelConfigStereo;
+#endif
+}
+
 QT_END_NAMESPACE
diff --git a/src/multimedia/darwin/qdarwinaudiodevice_p.h b/src/multimedia/darwin/qdarwinaudiodevice_p.h
index 687e43f34..ab6758118 100644
--- a/src/multimedia/darwin/qdarwinaudiodevice_p.h
+++ b/src/multimedia/darwin/qdarwinaudiodevice_p.h
@@ -77,6 +77,7 @@ public:
 private:
     QAudioFormat determinePreferredFormat() const;
     QString getDescription() const;
+    void getChannelLayout();
 #if defined(Q_OS_MACOS)
     AudioDeviceID m_deviceId;
 #endif
diff --git a/src/multimedia/darwin/qdarwinaudiosink.mm b/src/multimedia/darwin/qdarwinaudiosink.mm
index c4ade78f4..49443d234 100644
--- a/src/multimedia/darwin/qdarwinaudiosink.mm
+++ b/src/multimedia/darwin/qdarwinaudiosink.mm
@@ -555,11 +555,13 @@ bool QDarwinAudioSink::open()
         return false;
     }
 #endif
+    UInt32 size;
+
 
     // Set stream format
     m_streamFormat = CoreAudioUtils::toAudioStreamBasicDescription(m_audioFormat);
+    size = sizeof(m_streamFormat);
 
-    UInt32 size = sizeof(m_streamFormat);
     if (AudioUnitSetProperty(m_audioUnit,
                                 kAudioUnitProperty_StreamFormat,
                                 kAudioUnitScope_Input,