[SOLVED]: click when reproducing audio

_Mark_

Hello,
following the documentation I use this code to play a wave file:

@
m_sourceFile.setFileName(filename);
m_sourceFile.open(QIODevice::ReadOnly);

QAudioFormat format;
format.setSampleRate(44100);
format.setChannelCount(2);
format.setSampleSize(16);
format.setCodec("audio/pcm");
format.setByteOrder(QAudioFormat::LittleEndian);
format.setSampleType(QAudioFormat::SignedInt);

QAudioDeviceInfo info(QAudioDeviceInfo::defaultOutputDevice());
if (!info.isFormatSupported(format)) {
   qWarning() << "Raw audio format not supported by backend, cannot play audio.";
   return;
}

m_audio = new QAudioOutput(format, this);
m_audio->start(&m_sourceFile);

@

But when the audio start I hear a "click" noise.
Playing the some file with another player (aplay for example) there is no such a noise.

My platform is Raspberry Pi, Qt5.2, custom buildroot image.

vidar

What is the file Format of the audio file? That click is probably the header of the wave file?

_Mark_

It's a standard PCM Wave, 44100 Hz, 16-bit Stereo.
Do you mean Qt doesn't take care of the header section!?
So, how to correctly play a standard wave file?

I tried with QMediaPlayer but I get the following warning and no audio:

@
defaultServiceProvider::requestService(): no service found for - "org.qt-project.qt.mediaplayer"
@

vidar

You'll have to read the header yourself and set the output format accordingly. You can find the header definition here: https://ccrma.stanford.edu/courses/422/projects/WaveFormat/ or take a look at http://qt-project.org/doc/qt-4.8/demos-spectrum-app-wavfile-cpp.html

_Mark_

Skipping the header file leads to no click at all.
I'm going to parse the header to extract the actual audio format - anyway it's a pity Qt doesn't handle this by itself!

Thanks

_Mark_

Solved using the class you linked. Thanks again

vidar

I agree, I also think that Qt should provide the reading/writing of Audio files, at least for some basic formats ...