snd_pcm_readi 是ALSA(Advanced Linux Sound Architecture)库中的一个函数,用于从 PCM(Pulse Code Modulation)设备中读取音频数据。当你遇到 snd_pcm_readi 返回-5 时,这通常表示函数执行失败,并返回一个错误代码。在 ALSA 中,错误代码通常以负值表示。 1. 确认 snd_pcm_readi 函数返回 -5 的含义...
snd_pcm_readi/snd_pcm_writei错误处理 混音器设置 打开混音器 Attach关联设备 注册 加载 查找元素 获取/更改元素 示例程序 回环测试例程 总结 ALSA插件 学习总结 MP157开发板支持音频,板上搭载了音频编解码芯片CS42L51,支持播放以及录音功能。 ALSA概述 ALSA是Advanced Linux Sound Architecture(高级的Linux声音...
Read interleaved frames from a PCM. Parameters:pcm PCM handle buffer frames containing buffer size frames to be readReturns: a positive number of frames actually read otherwise a negative error code Return values: -EBADFD PCM is not in the right state (SND_PCM_STATE_PREPARED or SND_PCM_STATE...
==> snd_pcm_open(&handle, pcm_name, stream, open_mode); //打开一路pcm,刷新config配置 如果是"default",同时type等于SND_CONFIG_TYPE_COMPOUND那么这里对应"empty" static const char *const build_in_pcms[] = { "adpcm", "alaw", "copy", "dmix", "file", "hooks", "hw", "ladspa", "...
==> snd_pcm_open(&handle, pcm_name, stream, open_mode); //打开一路pcm,刷新config配置 如果是"default",同时type等于SND_CONFIG_TYPE_COMPOUND那么这里对应"empty" static const char *const build_in_pcms[] = { "adpcm", "alaw", "copy", "dmix", "file", "hooks", "hw", "ladspa", "...
阻塞模式下的ALSA 'snd_pcm_writei'行为是指在音频应用程序中使用ALSA库函数'snd_pcm_writei'进行音频数据写入时的一种工作模式。在阻塞模式下,当调用'snd_pcm_writei'函数时,如果音频缓冲区已满,则该函数会阻塞程序的执行,直到有足够的空间来写入音频数据为止。 ALSA(Advanced Linux Sound Architecture)是Linux...
\n"); exit (-1 ); } /* Open PCM device for playback. */ ...
_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 ...
.get_power_state = snd_ctl_hw_get_power_state, .read = snd_ctl_hw_read,};登录后复制调用snd_pcm_hw_open_fd创建hw PCM设备并配置对应的回调,snd_pcm_hw_open_fd函数原型如下int snd_pcm_hw_open_fd(snd_pcm_t **pcmp, const char *name, int fd, int sync_ptr_ioctl) ret = snd_pcm_ne...
Hi guys, I've got "ALSA lib pcm.c:7339:(snd_pcm_recover) underrun occurred" in todays master (FreeRDP version 1.1.0-dev (git 1.0.1-1519-g1ce9e)). I'm using these parameters: xfreerdp /u:user /vc:rdpsnd,sys:alsa,dev:default /mic +clipboar...