qt c++ QAudioOutput代码示例，播放MP3数据流音频

在Qt C++中，`QAudioOutput`是一个用于输出音频到声卡的类。以下是使用`QAudioOutput`播放MP3数据流的一个基本代码示例。这里假设你已经有一个包含MP3数据的`std::vector<unsigned char>`数组，我们将其命名为`mp3Data`。

#include <QAudio>
#include <QIODevice>

// 假设mp3Data是一个包含了MP3数据的字节序列
const QByteArray mp3Data;

class AudioPlayer {
public:
    explicit AudioPlayer(int sampleRate = 44100, int channels = 2) {
        outputDevice = new QAudioDeviceInfo(QAudio::defaultOutputDevice());
        if (!outputDevice->isValid()) {
            qCritical() << "Invalid audio device";
            return;
        }

        format = QAudioFormat(sampleRate, channels, QAudioFormat::Format_S16LE,
                              channels * sizeof(qint16), QAudio::StereoMode);
        output = new QAudioOutput(outputDevice, format);
        if (!output->start()) {
            qCritical() << "Failed to start audio output";
            return;
        }
    }

    ~AudioPlayer() {
        stop();
        delete output;
    }

    void play(const QByteArray& data) {
        audioBuffer = QByteArray(data.size(), 0);
        qint64 writtenBytes = audioBuffer.write(reinterpret_cast<const char*>(data.data()));
        if (writtenBytes != data.size()) {
            qWarning() << "Failed to write MP3 data to buffer";
            return;
        }

        qint64 bytesPlayed = output->write(audioBuffer);
        while (bytesPlayed > 0 && writtenBytes == data.size()) {
            bytesPlayed = output->write(audioBuffer);
        }
    }

private:
    QAudioDeviceInfo* outputDevice;
    QAudioFormat format;
    QAudioOutput* output;
    QByteArray audioBuffer;
};

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);

    AudioPlayer player;
    player.play(mp3Data);

    // 这里可以添加暂停、继续播放等操作，或者在play()循环中控制播放速度

    return app.exec();
}