linux录制pcm文件格式

arecord -f S16_LE -r 44100 -c 2 output.pcm

#include <stdio.h>
#include <stdlib.h>
#include <alsa/asoundlib.h>

#define SAMPLE_RATE 44100
#define CHANNELS 2
#define SAMPLE_SIZE 16
#define BUFFER_SIZE 4096

int main() {
    int err;
    snd_pcm_t *capture_handle;
    snd_pcm_hw_params_t *params;
    unsigned int val;
    int dir;
    snd_pcm_uframes_t frames;
    char *buffer;

    // Open PCM device for recording
    if ((err = snd_pcm_open(&capture_handle, "default", SND_PCM_STREAM_CAPTURE, 0)) < 0) {
        fprintf(stderr, "Cannot open audio device (%s)\n", snd_strerror(err));
        return 1;
    }

    // Allocate hardware parameters object
    snd_pcm_hw_params_malloc(&params);

    // Fill it in with default values
    snd_pcm_hw_params_any(capture_handle, params);

    // Set the desired hardware parameters
    snd_pcm_hw_params_set_access(capture_handle, params, SND_PCM_ACCESS_RW_INTERLEAVED);
    snd_pcm_hw_params_set_format(capture_handle, params, SND_PCM_FORMAT_S16_LE);
    snd_pcm_hw_params_set_rate_near(capture_handle, params, &val, &dir);
    snd_pcm_hw_params_set_channels(capture_handle, params, CHANNELS);

    // Apply the hardware parameters
    if ((err = snd_pcm_hw_params(capture_handle, params)) < 0) {
        fprintf(stderr, "Cannot set hardware parameters (%s)\n", snd_strerror(err));
        return 1;
    }

    // Allocate buffer to hold single period
    snd_pcm_hw_params_get_period_size(params, &frames, &dir);
    buffer = malloc(frames * CHANNELS * SAMPLE_SIZE / 8);

    // Open file for writing
    FILE *file = fopen("output.pcm", "wb");
    if (!file) {
        fprintf(stderr, "Cannot open file for writing\n");
        return 1;
    }

    // Capture audio data
    while (1) {
        snd_pcm_readi(capture_handle, buffer, frames);
        fwrite(buffer, 1, frames * CHANNELS * SAMPLE_SIZE / 8, file);
    }

    // Close file and PCM device
    fclose(file);
    snd_pcm_close(capture_handle);

    return 0;
}