对waveInOpen采集到的音频进行混音

要对通过waveInOpen采集到的音频进行混音，您可以使用Windows多媒体API中的waveOutOpen函数打开一个音频输出设备，并通过waveOutWrite函数将采集到的音频数据写入输出设备进行播放。下面是一个简单的示例代码：

#include <Windows.h>
#include <mmsystem.h>
#pragma comment(lib, "winmm.lib")

#define NUM_BUFFERS 3
#define BUFFER_SIZE 4096

HWAVEIN hWaveIn;
WAVEHDR waveHeaders[NUM_BUFFERS];
char buffers[NUM_BUFFERS][BUFFER_SIZE];

HWAVEOUT hWaveOut;
WAVEHDR waveOutHeaders[NUM_BUFFERS];
char outBuffers[NUM_BUFFERS][BUFFER_SIZE];

void CALLBACK WaveInProc(HWAVEIN hwi, UINT uMsg, DWORD_PTR dwInstance, DWORD_PTR dwParam1, DWORD_PTR dwParam2)
{
    if (uMsg == WIM_DATA)
    {
        // 混音处理，将录制的音频数据与已播放的音频数据进行混合
        LPWAVEHDR pHdr = (LPWAVEHDR)dwParam1;
        memcpy(outBuffers[0] + pHdr->dwBytesRecorded, pHdr->lpData, pHdr->dwBytesRecorded);

        // 将录音数据写入输出设备进行播放
        waveOutWrite(hWaveOut, pHdr, sizeof(WAVEHDR));

        // 释放已经处理完的缓冲区
        waveInUnprepareHeader(hwi, pHdr, sizeof(WAVEHDR));
        waveInPrepareHeader(hwi, pHdr, sizeof(WAVEHDR));
        waveInAddBuffer(hwi, pHdr, sizeof(WAVEHDR));
    }
}

void StartRecordingAndPlayback()
{
    // 设置录音参数
    WAVEFORMATEX format;
    format.wFormatTag = WAVE_FORMAT_PCM;
    format.nChannels = 1;
    format.nSamplesPerSec = 44100;
    format.wBitsPerSample = 16;
    format.nBlockAlign = format.nChannels * format.wBitsPerSample / 8;
    format.nAvgBytesPerSec = format.nSamplesPerSec * format.nBlockAlign;
    format.cbSize = 0;

    // 打开音频输入设备
    if (waveInOpen(&hWaveIn, WAVE_MAPPER, &format, (DWORD_PTR)WaveInProc, 0, CALLBACK_FUNCTION) != MMSYSERR_NOERROR)
    {
        printf("无法打开音频输入设备！\n");
        return;
    }

    // 初始化录音缓冲区
    for (int i = 0; i < NUM_BUFFERS; i++)
    {
        waveHeaders[i].lpData = buffers[i];
        waveHeaders[i].dwBufferLength = BUFFER_SIZE;
        waveHeaders[i].dwBytesRecorded = 0;
        waveHeaders[i].dwUser = 0;
        waveHeaders[i].dwFlags = 0;
        waveHeaders[i].dwLoops = 0;
        waveInPrepareHeader(hWaveIn, &waveHeaders[i], sizeof(WAVEHDR));
        waveInAddBuffer(hWaveIn, &waveHeaders[i], sizeof(WAVEHDR));
    }

    // 打开音频输出设备
    if (waveOutOpen(&hWaveOut, WAVE_MAPPER, &format, 0, 0, CALLBACK_NULL) != MMSYSERR_NOERROR)
    {
        printf("无法打开音频输出设备！\n");
        waveInClose(hWaveIn);
        return;
    }

    // 初始化音频输出缓冲区
    for (int i = 0; i < NUM_BUFFERS; i++)
    {
        waveOutHeaders[i].lpData = outBuffers[i];
        waveOutHeaders[i].dwBufferLength = BUFFER_SIZE;
        waveOutHeaders[i].dwBytesRecorded = 0;
        waveOutHeaders[i].dwUser = 0;
        waveOutHeaders[i].dwFlags = 0;
        waveOutHeaders[i].dwLoops = 0;
        waveOutPrepareHeader(hWaveOut, &waveOutHeaders[i], sizeof(WAVEHDR));
    }

    // 开始录音和播放
    waveInStart(hWaveIn);
    for (int i = 0; i < NUM_BUFFERS; i++)
    {
        waveOutWrite(hWaveOut, &waveOutHeaders[i], sizeof(WAVEHDR));
    }

    printf("开始录音和播放，请按任意键停止...\n");
    getchar();

    // 停止录音和播放
    waveInStop(hWaveIn);
    waveInReset(hWaveIn);
    waveInClose(hWaveIn);

    waveOutReset(hWaveOut);
    waveOutClose(hWaveOut);

    printf("录音和播放已停止。\n");
}

int main()
{
    StartRecordingAndPlayback();
    return 0;
}

这个示例代码会同时进行录音和播放，将录制的音频数据与已经播放的音频数据进行混合，并通过音频输出设备进行播放。

请注意，这只是一个简单的示例，用于演示如何进行音频混音。在实际应用中，您可能需要更复杂的算法和处理来实现更高质量的混音效果。

希望这可以帮助您进行音频混音操作！如果您还有其他问题，请随时提问。