audio模块录音流程alsa函数调用情况
时间: 2023-07-16 14:17:24 浏览: 73
在Linux系统中,使用ALSA(Advanced Linux Sound Architecture)库进行音频录制和播放。下面是一般的alsa录音流程和一些常用的alsa函数调用。
1. 打开设备:
```c
snd_pcm_open(&handle, "default", SND_PCM_STREAM_CAPTURE, 0);
```
2. 配置参数:
```c
snd_pcm_hw_params_t *params;
snd_pcm_hw_params_alloca(¶ms);
snd_pcm_hw_params_any(handle, params);
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_channels(handle, params, 1);
unsigned int sample_rate = 16000;
snd_pcm_hw_params_set_rate_near(handle, params, &sample_rate, 0);
snd_pcm_hw_params(handle, params);
```
3. 分配缓冲区:
```c
snd_pcm_uframes_t frames = 32;
char *buffer = (char *)malloc(frames * 2);
```
4. 开始录音:
```c
while (1) {
int nread = snd_pcm_readi(handle, buffer, frames);
if (nread == -EPIPE) {
snd_pcm_prepare(handle);
} else if (nread < 0) {
printf("Error from read: %s\n", snd_strerror(nread));
} else if (nread != (int)frames) {
printf("Short read, read %d frames\n", nread);
}
// 处理音频数据
}
```
5. 关闭设备:
```c
snd_pcm_close(handle);
```
以上是一般的alsa录音流程和一些常用的alsa函数调用,具体的实现要根据具体的应用场景进行调整。