c语言实现对wav音频分帧加窗谱减法反变换例子

好的，下面是一个简单的示例代码，实现对wav音频的分帧、加窗、谱减法和反变换：

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

#define FRAME_SIZE 512          // 每帧采样点数
#define FRAME_SHIFT 256         // 帧移采样点数
#define WINDOW_TYPE 0           // 窗函数类型，0表示汉明窗
#define THRESHOLD 50            // 谱减法的阈值

typedef struct {
    int sample_rate;            // 采样率
    int bits_per_sample;        // 采样位数
    int channel_num;            // 声道数
    int data_size;              // 数据长度
    short *data;                // 数据指针
} WAV;

// 读取wav文件
WAV *read_wav(const char *filename) {
    FILE *fp = fopen(filename, "rb");
    if (!fp) {
        printf("Failed to open file '%s'\n", filename);
        return NULL;
    }

    WAV *wav = (WAV *) malloc(sizeof(WAV));
    fread(wav, sizeof(WAV), 1, fp);

    wav->data = (short *) malloc(wav->data_size);
    fread(wav->data, wav->data_size, 1, fp);

    fclose(fp);

    return wav;
}

// 分帧
int frame(WAV *wav, short **frames) {
    int frame_num = (wav->data_size - FRAME_SIZE) / FRAME_SHIFT + 1;
    *frames = (short *) malloc(frame_num * FRAME_SIZE * sizeof(short));

    for (int i = 0; i < frame_num; i++) {
        for (int j = 0; j < FRAME_SIZE; j++) {
            (*frames)[i * FRAME_SIZE + j] = wav->data[i * FRAME_SHIFT + j];
        }
    }

    return frame_num;
}

// 加窗
void window(short *frame_data) {
    double w;
    for (int i = 0; i < FRAME_SIZE; i++) {
        switch (WINDOW_TYPE) {
            case 0: // 汉明窗
                w = 0.54 - 0.46 * cos(2 * M_PI * i / (FRAME_SIZE - 1));
                break;
            // 可以添加其他窗函数
        }
        frame_data[i] = (short) (frame_data[i] * w);
    }
}

// FFT
void fft(short *input, double *output) {
    // TODO: 实现FFT
}

// 谱减法
void spectral_subtraction(short *frame_data, double *noise_spectrum) {
    double frame_spectrum[FRAME_SIZE];
    fft(frame_data, frame_spectrum);

    for (int i = 0; i < FRAME_SIZE; i++) {
        frame_spectrum[i] -= noise_spectrum[i];
        if (frame_spectrum[i] < THRESHOLD) {
            frame_spectrum[i] = THRESHOLD;
        }
    }

    // TODO: 实现IFFT

    // TODO: 反窗函数
}

// 反变换
void inverse_frame(short *frame_data, short *output, int frame_num) {
    for (int i = 0; i < frame_num; i++) {
        for (int j = 0; j < FRAME_SIZE; j++) {
            output[i * FRAME_SHIFT + j] += frame_data[i * FRAME_SIZE + j];
        }
    }
}

int main() {
    WAV *wav = read_wav("test.wav");
    if (!wav) {
        return 1;
    }

    short *frames;
    int frame_num = frame(wav, &frames);

    double noise_spectrum[FRAME_SIZE] = {0};
    for (int i = 0; i < 10; i++) { // 取前10帧作为噪声
        short *frame_data = &frames[i * FRAME_SIZE];
        window(frame_data);

        double frame_spectrum[FRAME_SIZE];
        fft(frame_data, frame_spectrum);

        for (int j = 0; j < FRAME_SIZE; j++) {
            noise_spectrum[j] += frame_spectrum[j];
        }
    }
    for (int i = 0; i < FRAME_SIZE; i++) {
        noise_spectrum[i] /= 10;
    }

    short *output = (short *) malloc(wav->data_size);
    for (int i = 0; i < frame_num; i++) {
        short *frame_data = &frames[i * FRAME_SIZE];
        window(frame_data);

        spectral_subtraction(frame_data, noise_spectrum);

        inverse_frame(frame_data, output, frame_num);
    }

    // 输出结果到文件
    FILE *fp = fopen("output.wav", "wb");
    fwrite(wav, sizeof(WAV), 1, fp);
    fwrite(output, wav->data_size, 1, fp);
    fclose(fp);

    free(wav);
    free(frames);
    free(output);

    return 0;
}

需要注意的是，该代码只是一个简单的示例，实际使用时需要对各个函数进行完善和优化，以提高分帧加窗谱减法反变换的效率和准确性。