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使用C语言在Windows中创建PCM格式的音频文件

PCM文件里面存储的是经过数模转换后存储的二进制文件，需要支持的播放器才能播放。

1.保存do re mi fa so la ti do到PCM文件中

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#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <math.h>

// 定义 M_PI
#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif

#define SAMPLE_RATE 44100
#define NUM_CHANNELS 1
#define BITS_PER_SAMPLE 16
#define DURATION 0.25 // 每个音符的持续时间（秒）

void write_pcm_data(FILE* file, int16_t* data, int data_size) {
    fwrite(data, sizeof(int16_t), data_size, file);
}

int main() {
    FILE* file = fopen("output.pcm", "wb");
    if (!file) {
        printf("Failed to create PCM audio file\n");
        return 1;
    }

    int num_samples = SAMPLE_RATE * DURATION;
    int data_size = num_samples * NUM_CHANNELS * 8; // 8个音符
    int16_t* data = (int16_t*)malloc(data_size * sizeof(int16_t));

    if (!data) {
        printf("Memory allocation failed\n");
        fclose(file);
        return 1;
    }

    // 生成音阶数据
    int frequencies[] = { 261, 293, 329, 349, 392, 440, 493, 523 }; // C4, D4, E4, F4, G4, A4, B4, C5
    for (int i = 0; i < 8; i++) {
        int frequency = frequencies[i];
        for (int j = 0; j < num_samples; j++) {
            data[i * num_samples + j] = (int16_t)(32767 * sin(2 * M_PI * frequency * j / SAMPLE_RATE));
        }
    }

    write_pcm_data(file, data, num_samples * 8);

    free(data);
    fclose(file);

    printf("PCM audio file created successfully\n");
    return 0;
}

2.将PCM文件转为WAV格式后播放

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#define _CRT_SECURE_NO_WARNINGS
#include <windows.h>
#include <stdio.h>
#pragma comment(lib, "winmm.lib")

#define BUFFER_SIZE 4096

void playPCM(const char* filename, int sampleRate, int bitsPerSample, int channels) {
    // 打开PCM文件
    FILE* file = fopen(filename, "rb");
    if (!file) {
        printf("无法打开文件: %s\n", filename);
        return;
    }

    // 设置WAVE格式
    WAVEFORMATEX wfx;
    wfx.wFormatTag = WAVE_FORMAT_PCM;
    wfx.nChannels = channels;
    wfx.nSamplesPerSec = sampleRate;
    wfx.wBitsPerSample = bitsPerSample;
    wfx.nBlockAlign = (channels * bitsPerSample) / 8;
    wfx.nAvgBytesPerSec = sampleRate * wfx.nBlockAlign;
    wfx.cbSize = 0;

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

    // 创建缓冲区
    char buffer[BUFFER_SIZE];
    DWORD bytesRead;

    // 播放音频
    while ((bytesRead = fread(buffer, 1, BUFFER_SIZE, file)) > 0) {
        WAVEHDR waveHdr;
        waveHdr.lpData = buffer;
        waveHdr.dwBufferLength = bytesRead;
        waveHdr.dwFlags = 0;
        waveHdr.dwLoops = 0;

        // 准备并写入音频数据
        waveOutPrepareHeader(hWaveOut, &waveHdr, sizeof(WAVEHDR));
        waveOutWrite(hWaveOut, &waveHdr, sizeof(WAVEHDR));

        // 等待音频播放完成
        while (!(waveHdr.dwFlags & WHDR_DONE)) {
            Sleep(10);
        }

        waveOutUnprepareHeader(hWaveOut, &waveHdr, sizeof(WAVEHDR));
    }

    // 关闭音频输出设备
    waveOutClose(hWaveOut);
    fclose(file);
}

int main() {
    const char* filename = "output.pcm"; // PCM文件名
    int sampleRate = 44100; // 采样率
    int bitsPerSample = 16;  // 位深
    int channels = 2;        // 通道数

    playPCM(filename, sampleRate, bitsPerSample, channels);
    return 0;
}