Qt Stream Audio over TCP Connector in Real Time

Question

I am trying to understand how to transmit real-time audio over TCP sockets in Qt. What I'm using is QAudioInput on the client and QAudioOutput on the server. Both use the following format:

 QAudioFormat format; format.setChannelCount(1); format.setSampleRate(8000); format.setSampleSize(8); format.setCodec("audio/pcm"); format.setByteOrder(QAudioFormat::LittleEndian); format.setSampleType(QAudioFormat::UnSignedInt); 

I already have a simple socket server setup and managed to transfer audio from the client to the server using:

 //client QAudioInput *audio = new QAudioInput(format, this); audio->setBufferSize(1024); audio->start(socket); //server QAudioOutput *audio = new QAudioOutput(format, this); audio->setBufferSize(1024); 

Then on the server I get the data and add it to the QByteArray

On the server, I create a QBuffer and give it a QByteArray as soon as the client closes, and then play it like this:

 QByteArray *data = new QByteArray(); while(1) { if(socket->waitForReadyRead(30000)) data->append(socket->readAll()); else break; } QBuffer *buffer = new QBuffer(data); QEventLoop *loop = new QEventLoop(this); buffer->open(QIODevice::ReadOnly); audio->start(buffer); loop->exec(); 

This will play the entire stream AFTER the client closes. I am looking to change the server to play it in real time, but I cannot figure out how to do this. I approached real time, but it had loud clicks between packets and was delayed for several seconds.

I tried to play the stream as I sent it:

 audio->start(socket); 

but it does nothing. Maybe if I use QDataStream instead of using sockets directly?

Answer 1

To solve this problem, I simply increased setBufferSize from your 1024 to a higher value, for example, I used 8192, so you enable devices to read more data at a time, and I was able to transmit audio over my wireless network.

My cool design is a little different from yours, I have different classes for sockets and audio, and you can see it here .