如何使用QAudioInput从两个通道捕获音频信号

Question

我想使用QAudioInput.Audio捕获来自音频设备的声音。我有一个立体声（两个声道）输入信号，通常我只调用了setChannelCount（）函数，带有声道数，在这种情况下为2。我的目标是保存来自文件1中通道1的信号和来自文件2中通道2的信号。我的问题是如何分离两个信号。

Answer 1

Judging from the documentation of QAudioInput , you would need your own specialization of QIODevice in which you would override writeData in order to fan the data out into 2 files. I haven't tried to compile this but it should give you the general idea.

class MyIODevice : public QIODevice
{
public:
    MyIODevice(QIODevice* file1, QIODevice* file2)
      : m_file1(file1), m_file2(file2) {}

    qint64 writeData(const char* data, qint64 maxSize)
    {
        // for 32-bits with the channels interleaved.
        // I'm also making an assumption that QAudioInput will call this with
        // a complete frame of data.
        for (int i = 0; i < maxSize / 8; ++i)
        {
            m_file1->writeData(data, 4);
            data += 4;
            m_file2->writeData(data, 4);
            data += 4;
        }
    }
private:
    QIODevice* m_file1;
    QIODevice* m_file2;
};

As written this would only work with one audio format but could easily be made more general by passing some parameters about the format to the constructor, etc...