==> snd_pcm_open或者oss的snd_pcm_oss_f_reg.snd_pcm_oss_open,这就对应/dev/dsp了 ==> snd_pcm_open_file或者oss的snd_pcm_oss_open_file ==> snd_pcm_open_substream ==> soc_pcm_open /* ASoC PCM operations */ static struct snd_pcm_ops soc_pcm_ops = { .open = soc_pcm_open, ...
snd_pcm_open通过调用snd_config_update_ref来获取als.conf中的配置信息,参数保存至snd_config_t 。通过snd_pcm_open_noupdate 解析 snd_config_t 配置,snd_pcm_open_noupdate 函数原型如下static int snd_pcm_open_noupdate(snd_pcm_t **pcmp, snd_config_t *root, const char *name, snd_pcm_stream_t ...
==> snd_pcm_open_conf(pcmp, name, root, conf, stream, mode); ==> open_func = snd_dlobj_cache_lookup(open_name);将获得lib库中_snd_pcm_empty_open函数 所以open_func将等于_snd_pcm_empty_open _snd_pcm_empty_open _snd_pcm_asym_open _snd_pcm_plug_open _snd_pcm_softvol_open _snd_...
通过snd_pcm_open函数打开音频设备后,应用程序可以调用其他ALSA库函数来进行录制或播放操作。例如,可以使用snd_pcm_writei函数将音频数据写入到音频设备的缓冲区中,然后由音频设备进行播放;或者使用snd_pcm_readi函数从音频设备的缓冲区中读取音频数据,进行后续处理或保存。 除了snd_pcm_open函数外,ALSA库还提供了其他...
_snd_pcm_empty_open和snd_pcm_open_named_slave ==> snd_pcm_open_conf(pcmp, name, root, conf, stream, mode); ==> open_func = snd_dlobj_cache_lookup(open_name);将获得lib库中_snd_pcm_empty_open函数 所以open_func将等于_snd_pcm_empty_open _snd_pcm_empty_open _snd_pcm_asym_open ...
_snd_pcm_empty_open和snd_pcm_open_named_slave ==> snd_pcm_open_conf(pcmp, name, root, conf, stream, mode); ==> open_func = snd_dlobj_cache_lookup(open_name);将获得lib库中_snd_pcm_empty_open函数 所以open_func将等于_snd_pcm_empty_open _snd_pcm_empty_open _snd_pcm_asym_open ...
针对你提出的“undefined reference to `snd_pcm_open'”问题,我将从以下几个方面进行详细解答: 确认snd_pcm_open函数的来源库: snd_pcm_open函数是ALSA(Advanced Linux Sound Architecture)音频框架中的一部分,用于打开PCM设备。 检查是否已安装并正确链接了该库: 确保你的系统中已经安装了ALSA库。在Ubuntu系统...
我在Ubuntu 16.04主机上运行Ubuntu 12.04Docker容器。我在一些测试代码中使用SND_PCM_STREAM_PLAYBACK和SND_PCM_STREAM_CAPTURE流类型练习了'snd_pcm_open'/'snd_pcm_close‘操作。我不需要任何实际的声音/音频功能,但只需使用有效的句柄获取'snd_pcm_open‘返回0,然后在同一句柄上使用 ...
第三方类库和工具、代码、项目也很丰富。开发者可以快速、高效地使用 PHP 编写开发各类软件。到目前为止...
_snd_pcm_empty_open和snd_pcm_open_named_slave ==> snd_pcm_open_conf(pcmp, name, root, conf, stream, mode); ==> open_func = snd_dlobj_cache_lookup(open_name);将获得lib库中_snd_pcm_empty_open函数 所以open_func将等于_snd_pcm_empty_open _snd_pcm_empty_open _snd_pcm_asym_open ...