Add Wasapi audio backend

WASAPI is a Windows audio backend for low latency audio.
This backend works for WinRT as well as classic desktop apps.

Task-number: QTBUG-42287
Change-Id: I7a1b7b103b64fadc50a9955a9d59443791f6d026
Reviewed-by: Yoann Lopes <yoann.lopes@theqtcompany.com>

1 files changed, 164 insertions, 0 deletions

diff --git a/src/plugins/wasapi/qwasapiaudiodeviceinfo.cpp b/src/plugins/wasapi/qwasapiaudiodeviceinfo.cpp
new file mode 100644
index 000000000..283e8b740
--- /dev/null
+++ b/src/plugins/wasapi/qwasapiaudiodeviceinfo.cpp
@@ -0,0 +1,164 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd and/or its subsidiary(-ies).
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPLv3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qwasapiaudiodeviceinfo.h"
+#include "qwasapiutils.h"
+
+#include <Audioclient.h>
+
+QT_BEGIN_NAMESPACE
+
+Q_LOGGING_CATEGORY(lcMmDeviceInfo, "qt.multimedia.deviceinfo")
+
+QWasapiAudioDeviceInfo::QWasapiAudioDeviceInfo(QByteArray dev, QAudio::Mode mode)
+    : m_deviceName(dev)
+{
+    qCDebug(lcMmDeviceInfo) << __FUNCTION__ << dev << mode;
+    m_interface = QWasapiUtils::createOrGetInterface(dev, mode);
+
+    QAudioFormat referenceFormat = m_interface->m_mixFormat;
+
+    const int rates[] = {8000, 11025, 160000, 22050, 32000, 44100, 48000, 88200, 96000, 192000};
+    for (int rate : rates) {
+        QAudioFormat f = referenceFormat;
+        f.setSampleRate(rate);
+        if (isFormatSupported(f))
+            m_sampleRates.append(rate);
+    }
+
+    for (int i = 1; i <= 18; ++i) {
+        QAudioFormat f = referenceFormat;
+        f.setChannelCount(i);
+        if (isFormatSupported(f))
+            m_channelCounts.append(i);
+    }
+
+    const int sizes[] = {8, 12, 16, 20, 24, 32, 64};
+    for (int s : sizes) {
+        QAudioFormat f = referenceFormat;
+        f.setSampleSize(s);
+        if (isFormatSupported(f))
+            m_sampleSizes.append(s);
+    }
+
+    referenceFormat.setSampleType(QAudioFormat::SignedInt);
+    if (isFormatSupported(referenceFormat))
+        m_sampleTypes.append(QAudioFormat::SignedInt);
+
+    referenceFormat.setSampleType(QAudioFormat::Float);
+    if (isFormatSupported(referenceFormat))
+        m_sampleTypes.append(QAudioFormat::Float);
+}
+
+QWasapiAudioDeviceInfo::~QWasapiAudioDeviceInfo()
+{
+    qCDebug(lcMmDeviceInfo) << __FUNCTION__;
+}
+
+bool QWasapiAudioDeviceInfo::isFormatSupported(const QAudioFormat& format) const
+{
+    qCDebug(lcMmDeviceInfo) << __FUNCTION__ << format;
+
+    WAVEFORMATEX nfmt;
+    if (!QWasapiUtils::convertToNativeFormat(format, &nfmt))
+        return false;
+
+    WAVEFORMATEX closest;
+    WAVEFORMATEX *pClosest = &closest;
+    HRESULT hr;
+    hr = m_interface->m_client->IsFormatSupported(AUDCLNT_SHAREMODE_SHARED, &nfmt, &pClosest);
+
+    if (hr == S_OK) // S_FALSE is inside SUCCEEDED()
+        return true;
+
+    if (lcMmDeviceInfo().isDebugEnabled()) {
+        QAudioFormat f;
+        QWasapiUtils::convertFromNativeFormat(pClosest, &f);
+        qCDebug(lcMmDeviceInfo) << __FUNCTION__ << hr << "Closest match is:" << f;
+    }
+
+    return false;
+}
+
+QAudioFormat QWasapiAudioDeviceInfo::preferredFormat() const
+{
+    qCDebug(lcMmDeviceInfo) << __FUNCTION__;
+    return m_interface->m_mixFormat;
+}
+
+QString QWasapiAudioDeviceInfo::deviceName() const
+{
+    qCDebug(lcMmDeviceInfo) << __FUNCTION__;
+    return m_deviceName;
+}
+
+QStringList QWasapiAudioDeviceInfo::supportedCodecs()
+{
+    qCDebug(lcMmDeviceInfo) << __FUNCTION__;
+    return QStringList() << QStringLiteral("audio/pcm");
+}
+
+QList<int> QWasapiAudioDeviceInfo::supportedSampleRates()
+{
+    qCDebug(lcMmDeviceInfo) << __FUNCTION__;
+    return m_sampleRates;
+}
+
+QList<int> QWasapiAudioDeviceInfo::supportedChannelCounts()
+{
+    qCDebug(lcMmDeviceInfo) << __FUNCTION__;
+    return m_channelCounts;
+}
+
+QList<int> QWasapiAudioDeviceInfo::supportedSampleSizes()
+{
+    qCDebug(lcMmDeviceInfo) << __FUNCTION__;
+    return m_sampleSizes;
+}
+
+QList<QAudioFormat::Endian> QWasapiAudioDeviceInfo::supportedByteOrders()
+{
+    qCDebug(lcMmDeviceInfo) << __FUNCTION__;
+    return QList<QAudioFormat::Endian>() << m_interface->m_mixFormat.byteOrder();
+}
+
+QList<QAudioFormat::SampleType> QWasapiAudioDeviceInfo::supportedSampleTypes()
+{
+    qCDebug(lcMmDeviceInfo) << __FUNCTION__;
+    return m_sampleTypes;
+}
+
+QT_END_NAMESPACE