*/staticBOOLwodUpdatePlayedTotal(WINE_WAVEDEV* wwo,snd_pcm_status_t* ps){snd_pcm_sframes_tdelay;snd_pcm_sframes_tavail;snd_pcm_uframes_tbuf_size =0;snd_pcm_state_tstate; state = snd_pcm_state(wwo->pcm); avail = snd_pcm_avail_update(wwo->pcm);snd_pcm_hw_params_get_buffer_size...
}/* set buffer time */err = snd_pcm_hw_params_set_buffer_time_near(handle, params, buffer_time, &dir);if(err <0) {printf("Unable to set buffer time %i for playback: %s\n", buffer_time, snd_strerror(err));returnerr; } buffer_size = snd_pcm_hw_params_get_buffer_size(par...
thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: BackendSpecific { err: BackendSpecificError { description: "ALSA function 'snd_pcm_hw_params_set_buffer_size' failed with error 'EINVAL: Invalid argument'" } }', src/main.rs:25:10 ...
snd_pcm_hw_params_set_rate_near(sound->handle, hwparams, &extra_rate, 0); snd_pcm_uframes_t buffer_size; snd_pcm_hw_params_get_buffer_size_max(hwparams, &buffer_size); snd_pcm_hw_params_set_buffer_size_near(sound->handle, hwparams, &buffer_size); snd_pcm_uframes_t period_size...
打开PCM设备 设置硬件参数 读/写数据 PCM播放示例代码 PCM录音示例代码 使用异步方法 snd_async_add_pcm_handler()函数 snd_pcm_avail_update()函数 PCM异步播放示例 PCM异步录音示例 使用poll()函数 使用poll I/O多路复用实现读写 PCM播放示例 PCM录音示例 PCM设备状态 PCM播放——加入状态控制 snd_pcm_readi/...
if the buffer size has already been set to 16384, and the period_size is trying to be set to 8196, why do I get the following results: -period_size=8196 dir=0; err = snd_pcm_hw_params_set_period_size_near(this->audio_fd, params, &period_size, &dir); result: period_size=8196...
PCM硬件参数,这是一个成员不公开的结构: typedefstruct_snd_pcm_hw_paramssnd_pcm_hw_params_t; PCM的流类型,主要指播放和录音两种: /** PCM stream (direction) */typedefenum_snd_pcm_stream{/** Playback stream */SND_PCM_STREAM_PLAYBACK=0,/** Capture stream */SND_PCM_STREAM_CAPTURE,SND_PCM...
本文主要详细分析snd_pcm_open。snd_pcm_open顺序图代码详细分析 (以播放为例)问题引入alsa_utils aplay.c 中的播放接口采用函数指针实现,具体定义如下static snd_pcm_sframes_t (*writei_func)(snd_pcm_t *handle, const void *buffer, snd_pcm_uframes_t size);登录后复制赋值如下 writei_func = snd_...
size 是要写入的字节数。确保这些参数都正确无误。特别是 pcm 指针,它必须指向一个已经成功打开并正确配置的 PCM 设备。 3. 确认音频设备状态 在调用 snd_pcm_writei 之前,需要确保音频设备已经正确打开、配置和启动。这通常涉及以下几个步骤: 使用snd_pcm_open 打开PCM 设备。 使用snd_pcm_hw_params 和snd_...
snd_pcm_hw_t *hw = pcm->private_data; void *ptr; int err; if (hw->sync_ptr == NULL) { //如果还没有mmap,那么执行mmap映射内核空间驱动使用的声音缓冲区 ptr = mmap(NULL, page_align(sizeof(struct sndrv_pcm_mmap_control)), PROT_READ|PROT_WRITE, MAP_FILE|MAP_SHARED, hw->fd, SNDR...