class AudioGenerator : public QIODevice { Q_OBJECT public: qint64 readData(char *data, qint64 maxLen) override { // This is called by the audio engine when it needs more data. // You have ~10-50ms to fill this buffer. generateSamples(data, maxLen); return maxLen; } void start() { QAudioFormat format; format.setSampleRate(48000); format.setChannelCount(2); format.setSampleFormat(QAudioFormat::Int16); m_audio = new QAudioSink(format, this); m_audio->start(this); // Qt pulls data automatically } private: QAudioSink *m_audio; };
For 80% of applications—media players, notification systems, game sound effects, or simple synthesizers—Qt Multimedia is the fastest way to ship audio on Windows, macOS, Linux, Android, and iOS from a single codebase. Just remember to keep your audio callbacks lean, mix manually, and always respect the hardware's native format. qt audio engine
Have you built an audio tool with Qt? Let me know about your experience with latency and GStreamer backends in the comments. class AudioGenerator : public QIODevice { Q_OBJECT public:
For a sequencer or drum machine, do not rely on QTimer . Timers are not accurate enough. Instead, use a QAudioSink with a small buffer size and use the number of bytes processed to calculate the exact playback position in samples. Qt makes network audio surprisingly easy. You can pipe a QNetworkAccessManager reply directly into a buffer. Just remember to keep your audio callbacks lean,
If you are starting a new project today, stick to the QAudioSink / QAudioSource C++ classes for engine logic, and expose only control properties (volume, play/pause) to the GUI layer via signals. Is Qt a "professional" audio engine framework like JUCE or PortAudio? No. But is it a highly capable, cross-platform solution that integrates seamlessly with a GUI? Absolutely.
When developers think of Qt, they typically imagine polished GUI applications, QML interfaces, or perhaps embedded systems. But lurking beneath the surface of this powerful framework is a surprisingly capable audio module: Qt Multimedia .