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# audiodevices.cpp Example File

multimedia/audiodevices/audiodevices.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2015 The Qt Company Ltd.
     ** Contact: http://www.qt.io/licensing/
     **
     ** This file is part of the examples of the Qt Toolkit.
     **
     ** $QT_BEGIN_LICENSE:BSD$
     ** You may use this file under the terms of the BSD license as follows:
     **
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     ** modification, are permitted provided that the following conditions are
     ** met:
     **   * Redistributions of source code must retain the above copyright
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     **     notice, this list of conditions and the following disclaimer in
     **     the documentation and/or other materials provided with the
     **     distribution.
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     **     contributors may be used to endorse or promote products derived
     **     from this software without specific prior written permission.
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     ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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     #include <QAudioDeviceInfo>

     #include "audiodevices.h"

     // Utility functions for converting QAudioFormat fields into text

     QString toString(QAudioFormat::SampleType sampleType)
     {
         QString result;
         switch (sampleType) {
         case QAudioFormat::SignedInt:
             result = "SignedInt";
             break;
         case QAudioFormat::UnSignedInt:
             result = "UnSignedInt";
             break;
         case QAudioFormat::Float:
             result = "Float";
             break;
         default:
         case QAudioFormat::Unknown:
             result = "Unknown";
             break;
         }
         return result;
     }

     QString toString(QAudioFormat::Endian endian)
     {
         QString result("Unknown");
         switch (endian) {
         case QAudioFormat::LittleEndian:
             result = "LittleEndian";
             break;
         case QAudioFormat::BigEndian:
             result = "BigEndian";
             break;
         }
         return result;
     }

     AudioDevicesBase::AudioDevicesBase(QWidget *parent, Qt::WFlags f)
         : QMainWindow(parent, f)
     {
         setupUi(this);
     }

     AudioDevicesBase::~AudioDevicesBase() {}

     AudioTest::AudioTest(QWidget *parent, Qt::WFlags f)
         : AudioDevicesBase(parent, f)
     {
         mode = QAudio::AudioOutput;

         connect(testButton, SIGNAL(clicked()), SLOT(test()));
         connect(modeBox, SIGNAL(activated(int)), SLOT(modeChanged(int)));
         connect(deviceBox, SIGNAL(activated(int)), SLOT(deviceChanged(int)));
         connect(frequencyBox, SIGNAL(activated(int)), SLOT(freqChanged(int)));
         connect(channelsBox, SIGNAL(activated(int)), SLOT(channelChanged(int)));
         connect(codecsBox, SIGNAL(activated(int)), SLOT(codecChanged(int)));
         connect(sampleSizesBox, SIGNAL(activated(int)), SLOT(sampleSizeChanged(int)));
         connect(sampleTypesBox, SIGNAL(activated(int)), SLOT(sampleTypeChanged(int)));
         connect(endianBox, SIGNAL(activated(int)), SLOT(endianChanged(int)));
         connect(populateTableButton, SIGNAL(clicked()), SLOT(populateTable()));

         modeBox->setCurrentIndex(0);
         modeChanged(0);
         deviceBox->setCurrentIndex(0);
         deviceChanged(0);
     }

     AudioTest::~AudioTest()
     {
     }

     void AudioTest::test()
     {
         // tries to set all the settings picked.
         testResult->clear();

         if (!deviceInfo.isNull()) {
             if (deviceInfo.isFormatSupported(settings)) {
                 testResult->setText(tr("Success"));
                 nearestFreq->setText("");
                 nearestChannel->setText("");
                 nearestCodec->setText("");
                 nearestSampleSize->setText("");
                 nearestSampleType->setText("");
                 nearestEndian->setText("");
             } else {
                 QAudioFormat nearest = deviceInfo.nearestFormat(settings);
                 testResult->setText(tr("Failed"));
                 nearestFreq->setText(QString("%1").arg(nearest.frequency()));
                 nearestChannel->setText(QString("%1").arg(nearest.channels()));
                 nearestCodec->setText(nearest.codec());
                 nearestSampleSize->setText(QString("%1").arg(nearest.sampleSize()));
                 nearestSampleType->setText(toString(nearest.sampleType()));
                 nearestEndian->setText(toString(nearest.byteOrder()));
             }
         }
         else
             testResult->setText(tr("No Device"));
     }

     void AudioTest::modeChanged(int idx)
     {
         testResult->clear();

         // mode has changed
         if (idx == 0)
             mode = QAudio::AudioInput;
         else
             mode = QAudio::AudioOutput;

         deviceBox->clear();
         foreach (const QAudioDeviceInfo &deviceInfo, QAudioDeviceInfo::availableDevices(mode))
             deviceBox->addItem(deviceInfo.deviceName(), QVariant::fromValue(deviceInfo));

         deviceBox->setCurrentIndex(0);
         deviceChanged(0);
     }

     void AudioTest::deviceChanged(int idx)
     {
         testResult->clear();

         if (deviceBox->count() == 0)
             return;

         // device has changed
         deviceInfo = deviceBox->itemData(idx).value<QAudioDeviceInfo>();

         frequencyBox->clear();
         QList<int> freqz = deviceInfo.supportedFrequencies();
         for(int i = 0; i < freqz.size(); ++i)
             frequencyBox->addItem(QString("%1").arg(freqz.at(i)));
         if(freqz.size())
             settings.setFrequency(freqz.at(0));

         channelsBox->clear();
         QList<int> chz = deviceInfo.supportedChannels();
         for(int i = 0; i < chz.size(); ++i)
             channelsBox->addItem(QString("%1").arg(chz.at(i)));
         if(chz.size())
             settings.setChannels(chz.at(0));

         codecsBox->clear();
         QStringList codecz = deviceInfo.supportedCodecs();
         for (int i = 0; i < codecz.size(); ++i)
             codecsBox->addItem(QString("%1").arg(codecz.at(i)));
         if (codecz.size())
             settings.setCodec(codecz.at(0));
         // Add false to create failed condition!
         codecsBox->addItem("audio/test");

         sampleSizesBox->clear();
         QList<int> sampleSizez = deviceInfo.supportedSampleSizes();
         for (int i = 0; i < sampleSizez.size(); ++i)
             sampleSizesBox->addItem(QString("%1").arg(sampleSizez.at(i)));
         if (sampleSizez.size())
             settings.setSampleSize(sampleSizez.at(0));

         sampleTypesBox->clear();
         QList<QAudioFormat::SampleType> sampleTypez = deviceInfo.supportedSampleTypes();

         for (int i = 0; i < sampleTypez.size(); ++i)
             sampleTypesBox->addItem(toString(sampleTypez.at(i)));
         if (sampleTypez.size())
             settings.setSampleType(sampleTypez.at(0));

         endianBox->clear();
         QList<QAudioFormat::Endian> endianz = deviceInfo.supportedByteOrders();
         for (int i = 0; i < endianz.size(); ++i)
             endianBox->addItem(toString(endianz.at(i)));
         if (endianz.size())
             settings.setByteOrder(endianz.at(0));

         allFormatsTable->clearContents();
     }

     void AudioTest::populateTable()
     {
         int row = 0;

         QAudioFormat format;
         foreach (QString codec, deviceInfo.supportedCodecs()) {
             format.setCodec(codec);
             foreach (int frequency, deviceInfo.supportedFrequencies()) {
                 format.setFrequency(frequency);
                 foreach (int channels, deviceInfo.supportedChannels()) {
                     format.setChannels(channels);
                     foreach (QAudioFormat::SampleType sampleType, deviceInfo.supportedSampleTypes()) {
                         format.setSampleType(sampleType);
                         foreach (int sampleSize, deviceInfo.supportedSampleSizes()) {
                             format.setSampleSize(sampleSize);
                             foreach (QAudioFormat::Endian endian, deviceInfo.supportedByteOrders()) {
                                 format.setByteOrder(endian);
                                 if (deviceInfo.isFormatSupported(format)) {
                                     allFormatsTable->setRowCount(row + 1);

                                     QTableWidgetItem *codecItem = new QTableWidgetItem(format.codec());
                                     allFormatsTable->setItem(row, 0, codecItem);

                                     QTableWidgetItem *frequencyItem = new QTableWidgetItem(QString("%1").arg(format.frequency()));
                                     allFormatsTable->setItem(row, 1, frequencyItem);

                                     QTableWidgetItem *channelsItem = new QTableWidgetItem(QString("%1").arg(format.channels()));
                                     allFormatsTable->setItem(row, 2, channelsItem);

                                     QTableWidgetItem *sampleTypeItem = new QTableWidgetItem(toString(format.sampleType()));
                                     allFormatsTable->setItem(row, 3, sampleTypeItem);

                                     QTableWidgetItem *sampleSizeItem = new QTableWidgetItem(QString("%1").arg(format.sampleSize()));
                                     allFormatsTable->setItem(row, 4, sampleSizeItem);

                                     QTableWidgetItem *byteOrderItem = new QTableWidgetItem(toString(format.byteOrder()));
                                     allFormatsTable->setItem(row, 5, byteOrderItem);

                                     ++row;
                                 }
                             }
                         }
                     }
                 }
             }
         }
     }

     void AudioTest::freqChanged(int idx)
     {
         // freq has changed
         settings.setFrequency(frequencyBox->itemText(idx).toInt());
     }

     void AudioTest::channelChanged(int idx)
     {
         settings.setChannels(channelsBox->itemText(idx).toInt());
     }

     void AudioTest::codecChanged(int idx)
     {
         settings.setCodec(codecsBox->itemText(idx));
     }

     void AudioTest::sampleSizeChanged(int idx)
     {
         settings.setSampleSize(sampleSizesBox->itemText(idx).toInt());
     }

     void AudioTest::sampleTypeChanged(int idx)
     {
         switch (sampleTypesBox->itemText(idx).toInt()) {
             case QAudioFormat::SignedInt:
                 settings.setSampleType(QAudioFormat::SignedInt);
                 break;
             case QAudioFormat::UnSignedInt:
                 settings.setSampleType(QAudioFormat::UnSignedInt);
                 break;
             case QAudioFormat::Float:
                 settings.setSampleType(QAudioFormat::Float);
         }
     }

     void AudioTest::endianChanged(int idx)
     {
         switch (endianBox->itemText(idx).toInt()) {
             case QAudioFormat::LittleEndian:
                 settings.setByteOrder(QAudioFormat::LittleEndian);
                 break;
             case QAudioFormat::BigEndian:
                 settings.setByteOrder(QAudioFormat::BigEndian);
         }
     }