utils.cpp Example File

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 #include <QtMultimedia/QAudioFormat>
 #include "utils.h"

 qint64 audioDuration(const QAudioFormat &format, qint64 bytes)
 {
     return (bytes * 1000000) /
         (format.frequency() * format.channels() * (format.sampleSize() / 8));
 }

 qint64 audioLength(const QAudioFormat &format, qint64 microSeconds)
 {
    return (format.frequency() * format.channels() * (format.sampleSize() / 8))
        * microSeconds / 1000000;
 }

 qreal nyquistFrequency(const QAudioFormat &format)
 {
     return format.frequency() / 2;
 }

 QString formatToString(const QAudioFormat &format)
 {
     QString result;

     if (QAudioFormat() != format) {
         if (format.codec() == "audio/pcm") {
             Q_ASSERT(format.sampleType() == QAudioFormat::SignedInt);

             const QString formatEndian = (format.byteOrder() == QAudioFormat::LittleEndian)
                 ?   QString("LE") : QString("BE");

             QString formatType;
             switch(format.sampleType()) {
             case QAudioFormat::SignedInt:
                 formatType = "signed";
                 break;
             case QAudioFormat::UnSignedInt:
                 formatType = "unsigned";
                 break;
             case QAudioFormat::Float:
                 formatType = "float";
                 break;
             case QAudioFormat::Unknown:
                 formatType = "unknown";
                 break;
             }

             QString formatChannels = QString("%1 channels").arg(format.channels());
             switch (format.channels()) {
             case 1:
                 formatChannels = "mono";
                 break;
             case 2:
                 formatChannels = "stereo";
                 break;
             }

             result = QString("%1 Hz %2 bit %3 %4 %5")
                 .arg(format.frequency())
                 .arg(format.sampleSize())
                 .arg(formatType)
                 .arg(formatEndian)
                 .arg(formatChannels);
         } else {
             result = format.codec();
         }
     }

     return result;
 }

 bool isPCM(const QAudioFormat &format)
 {
     return (format.codec() == "audio/pcm");
 }

 bool isPCMS16LE(const QAudioFormat &format)
 {
     return (isPCM(format) &&
             format.sampleType() == QAudioFormat::SignedInt &&
             format.sampleSize() == 16 &&
             format.byteOrder() == QAudioFormat::LittleEndian);
 }

 const qint16  PCMS16MaxValue     =  32767;
 const quint16 PCMS16MaxAmplitude =  32768; // because minimum is -32768

 qreal pcmToReal(qint16 pcm)
 {
     return qreal(pcm) / PCMS16MaxAmplitude;
 }

 qint16 realToPcm(qreal real)
 {
     return real * PCMS16MaxValue;
 }