linux音视频驱动程序

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

int main() {
    snd_pcm_t *handle;
    snd_pcm_hw_params_t *params;
    int dir;
    snd_pcm_uframes_t frames;
    char *buffer;
    int size;

    // 打开PCM设备
    snd_pcm_open(&handle, "default", SND_PCM_STREAM_PLAYBACK, 0);
    snd_pcm_hw_params_malloc(&params);
    snd_pcm_hw_params_any(handle, params);

    // 设置PCM参数
    snd_pcm_hw_params_set_access(handle, params, SND_PCM_ACCESS_RW_INTERLEAVED);
    snd_pcm_hw_params_set_format(handle, params, SND_PCM_FORMAT_S16_LE);
    snd_pcm_hw_params_set_rate(handle, params, 44100, 0);
    snd_pcm_hw_params_set_channels(handle, params, 2);

    // 应用参数
    snd_pcm_hw_params(handle, params);

    // 准备播放缓冲区
    snd_pcm_hw_params_get_period_size(params, &frames, &dir);
    size = frames * 2 * 2; // 2 bytes/sample, 2 channels
    buffer = (char *)malloc(size);

    // 播放音频数据
    while (1) {
        // 填充音频数据到缓冲区
        // ...
        snd_pcm_writei(handle, buffer, frames);
    }

    // 释放资源
    free(buffer);
    snd_pcm_hw_params_free(params);
    snd_pcm_close(handle);

    return 0;
}