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使用C语言在Windows中创建WAV格式的音频文件

1. 创建WAV格式的音频文件

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#define _CRT_SECURE_NO_WARNINGS

#include <stdio.h>
#include <math.h>
#include <stdint.h>
#include <string.h>
#include <stdlib.h>

#define SAMPLE_RATE 44100
#define DURATION 0.1 // 每个音符的持续时间（秒）
#define AMPLITUDE 32767 // 最大振幅（16位音频）

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

// 音符频率（C4, D4, E4, F4, G4, A4, B4, C5）
double frequencies[] = { 261.63, 293.66, 329.63, 349.23, 392.00, 440.00, 493.88, 523.25 };

// WAV 文件头结构
typedef struct {
    char riff[4];        // "RIFF"
    uint32_t overall_size; // 文件总大小
    char wave[4];        // "WAVE"
    char fmt_chunk_marker[4]; // "fmt "
    uint32_t length_of_fmt; // 4
    uint16_t format_type; // 1
    uint16_t channels;     // 1
    uint32_t sample_rate;  // 44100
    uint32_t byterate;     // SampleRate * NumChannels * BitsPerSample/8
    uint16_t block_align;  // NumChannels * BitsPerSample/8
    uint16_t bits_per_sample; // 16
    char data_chunk_header[4]; // "data"
    uint32_t data_size;    // 采样数据大小
} WavHeader;

void writeWavHeader(FILE* file, int dataSize) {
    WavHeader header;
    memcpy(header.riff, "RIFF", 4);
    header.overall_size = 36 + dataSize; // 36 + Subchunk2Size
    memcpy(header.wave, "WAVE", 4);
    memcpy(header.fmt_chunk_marker, "fmt ", 4);
    header.length_of_fmt = 16; // 16 for PCM
    header.format_type = 1; // PCM
    header.channels = 1; // 单声道
    header.sample_rate = SAMPLE_RATE; // 44.1kHz
    header.byterate = SAMPLE_RATE * header.channels * (16 / 8);
    header.block_align = header.channels * (16 / 8);
    header.bits_per_sample = 16; // 16位
    memcpy(header.data_chunk_header, "data", 4);
    header.data_size = dataSize;

    fwrite(&header, sizeof(WavHeader), 1, file);
}

void generateTone(FILE* file, double frequency) {
    int numSamples = (int)(SAMPLE_RATE * DURATION);
    for (int i = 0; i < numSamples; i++) {
        double sample = AMPLITUDE * sin(2.0 * M_PI * frequency * ((double)i / SAMPLE_RATE));
        int16_t sampleValue = (int16_t)sample;
        fwrite(&sampleValue, sizeof(int16_t), 1, file);
    }
}

int main() {
    FILE* file = fopen("notes.wav", "wb");
    if (!file) {
        printf("无法创建文件\n");
        return 1;
    }

    // 生成音符
    for (int i = 0; i < 8; i++) {
        generateTone(file, frequencies[i]);
    }

    // 写入 WAV 文件头
    fseek(file, 0, SEEK_END);
    int dataSize = ftell(file) - sizeof(WavHeader);
    fseek(file, 0, SEEK_SET);
    writeWavHeader(file, dataSize);

    fclose(file);
    printf("WAV 文件已生成：notes.wav\n");
    return 0;
}