python - 如何将 python Popen 与 espeak 和 aplay 一起使用

Question

我正在打电话

espeak -ves -s130 'HEY' --stdout | aplay -D 'sysdefault'

通过 subprocess.Popen，用

espeak_process = Popen(["espeak", "-ves -s100 'HEY' --stdout"], stdout=subprocess.PIPE)
aplay_process = Popen(["aplay", "-D 'sysdefault'"], stdin=espeak_process.stdout, stdout=subprocess.PIPE)

但是没用

ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM  'sysdefault'
aplay: main:682: audio open error: No such file or directory

知道如何实现吗？ 谢谢

Answer 1

你的例子相当于在 shell 中输入:

$ espeak '-ves -s100 \'HEY\' --stdout'
$ aplay '-D \'sysdefault\''

这显然是错误的。每个列表条目都是传递给可执行文件的一个参数(argv 条目)，您这边不需要转义/引用。所以你想使用:

["aplay", "-D", "sysdefault"]
["espeak", "-ves", "-s100", "HEY", "--stdout"],

另见 the documentation (强调我的):

args is required for all calls and should be a string, or a sequence of program arguments. Providing a sequence of arguments is generally preferred, as it allows the module to take care of any required escaping and quoting of arguments (e.g. to permit spaces in file names). If passing a single string, either shell must be True (see below) or else the string must simply name the program to be executed without specifying any arguments.