C语言读取wav音频实例

你好！很高兴为你解答问题。以下是 C语言读取wav音频文件的示例代码：

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h> // For uint8_t, etc.
#include <stdbool.h> // For true/false

/*
 * Struct representing the format chunk of a wav file.
 */
typedef struct {
    uint16_t audio_format;
    uint16_t num_channels;
    uint32_t sample_rate;
    uint32_t byte_rate;
    uint16_t block_align;
    uint16_t bits_per_sample;
} wav_format_t;

/*
 * Read a little-endian unsigned 16-bit value from a file.
 */
uint16_t read_le_u16(FILE* file) {
    uint8_t lo, hi;
    lo = fgetc(file);
    hi = fgetc(file);
    return (hi << 8) | lo;
}

/*
 * Read a little-endian unsigned 32-bit value from a file.
 */
uint32_t read_le_u32(FILE* file) {
    uint8_t b0, b1, b2, b3;
    b0 = fgetc(file);
    b1 = fgetc(file);
    b2 = fgetc(file);
    b3 = fgetc(file);
    return (b3 << 24) | (b2 << 16) | (b1 << 8) | b0;
}

/*
 * Read a format chunk from a wav file.
 */
bool read_format(FILE* file, wav_format_t* format) {
    uint32_t chunk_size;
    uint16_t audio_format;

    // Read chunk size and audio format.
    if (fread(&chunk_size, 4, 1, file) != 1 ||
        fread(&audio_format, 2, 1, file) != 1) {
        return false;
    }
    format->audio_format = audio_format;

    // If audio format is not PCM, we can't handle the file.
    if (audio_format != 1) {
        return false;
    }

    // Read the remaining fields of the format chunk.
    format->num_channels = read_le_u16(file);
    format->sample_rate = read_le_u32(file);
    format->byte_rate = read_le_u32(file);
    format->block_align = read_le_u16(file);
    format->bits_per_sample = read_le_u16(file);

    // We've read the format chunk successfully.
    return true;
}

/*
 * Read a data chunk from a wav file.
 */
bool read_data(FILE* file, uint8_t** data, uint32_t* num_samples, uint16_t num_channels, uint16_t bits_per_sample) {
    uint32_t chunk_size;

    // Read the chunk size.
    if (fread(&chunk_size, 4, 1, file) != 1) {
        return false;
    }

    // Allocate memory for the audio data.
    *data = (uint8_t*)malloc(chunk_size);
    if (!*data) {
        return false;
    }

    // Read the audio data.
    if (fread(*data, chunk_size, 1, file) != 1) {
        free(*data);
        return false;
    }

    // Calculate the number of audio samples.
    *num_samples = chunk_size / ((bits_per_sample / 8) * num_channels);

    // We've read the audio data successfully.
    return true;
}

/*
 * Load a wav file into memory.
 */
bool load_wav_file(const char* path, uint8_t** data, uint32_t* num_samples, wav_format_t* format) {
    FILE* file;

    // Open the file.
    file = fopen(path, "rb");
    if (!file) {
        return false;
    }

    // Read the RIFF header.
    if (fgetc(file) != 'R' || fgetc(file) != 'I' ||
        fgetc(file) != 'F' || fgetc(file) != 'F') {
        fclose(file);
        return false;
    }

    // Skip the file size field.
    fseek(file, 4, SEEK_CUR);

    // Read the WAVE header.
    if (fgetc(file) != 'W' || fgetc(file) != 'A' ||
        fgetc(file) != 'V' || fgetc(file) != 'E') {
        fclose(file);
        return false;
    }

    // Read the format chunk.
    if (!read_format(file, format)) {
        fclose(file);
        return false;
    }

    // Seek to the beginning of the next chunk.
    while (fgetc(file) != 'd' || fgetc(file) != 'a' ||
           fgetc(file) != 't' || fgetc(file) != 'a') {
        if (feof(file)) {
            fclose(file);
            return false;
        }
    }

    // Read the data chunk.
    if (!read_data(file, data, num_samples, format->num_channels, format->bits_per_sample)) {
        fclose(file);
        return false;
    }

    // Close the file.
    fclose(file);

    // We've loaded the wav file successfully.
    return true;
}

int main() {
    uint8_t* data;
    uint32_t num_samples;
    wav_format_t format;

    if (load_wav_file("example.wav", &data, &num_samples, &format)) {
        printf("Loaded wav file with %u samples, %u channels, %u Hz, %u bits per sample\n",
               num_samples, format.num_channels,
               format.sample_rate, format.bits_per_sample);
        // Do something with the audio data here...
        free(data);
    } else {
        printf("Failed to load wav file\n");
    }

    return 0;
}

这段代码可以读取一个 wav 格式的音频文件，并将其缓存在内存中。如果加载成功，会输出音频的采样率、通道数、样本位数等信息。你可以在 "// Do something with the audio data here..." 这个注释后面做自己需要的处理。希望能对你有帮助！