问题
Overview: So this is a follow up to my last problem (here). I will be posting a full answer on that very soon. I'm able to get pocketsphinx to recognize audio input from my PS3 Eye in Python via Gstreamer. By specifying the correct alsa device ( hw:1 in my case ).
ISSUE: My next issue seems to involve a tiny race condition involving my Microphone already being in use and needing to be able to record something.
Imagine the following:
- I start up my python daemon, and it's currently listening.
- I speak to my microphone and say Hello Scarlett ( Pocketsphinx matches the keyword and begins RECORDING all input now )
- Audio is meant to be recorded to a wav file in the /tmp/ directory and is suppose to stay there till silence is detected
Now it seems as though, when I begin step 3, the Microphone stops working AGAIN. I ran with some verbose options to try to figure out what happened but checking my /tmp/ directory told me everything:
pi@scarlettpi ~ $ ls -lta /tmp/ | grep wav
-rw-r--r-- 1 pi pi 0 Aug 13 20:57 fsdgjdspi.wav
pi@scarlettpi ~ $
File size is 0 bytes. Nothing is getting recorded.
To confirm that I ran the process through strace and confirmed what I suspected:
pi@scarlettpi ~ $ strace -p 12416 | tee -a pi.strace.log 2>&1
Process 12416 attached - interrupt to quit
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, -1) = 1 ([{fd=3, revents=POLLIN}])
read(3, "\1\0\0\0\0\0\0\0", 16) = 8
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, -1) = 1 ([{fd=3, revents=POLLIN}])
read(3, "\1\0\0\0\0\0\0\0", 16) = 8
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, -1) = 1 ([{fd=3, revents=POLLIN}])
read(3, "\1\0\0\0\0\0\0\0", 16) = 8
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, -1) = 1 ([{fd=3, revents=POLLIN}])
read(3, "\1\0\0\0\0\0\0\0", 16) = 8
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, -1) = 1 ([{fd=3, revents=POLLIN}])
read(3, "\1\0\0\0\0\0\0\0", 16) = 8
ioctl(7, 0x80044121, 0xbebd764c) = 0
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
futex(0x1e47f34, FUTEX_WAKE_OP_PRIVATE, 1, 1, 0x1e47f30, {FUTEX_OP_SET, 0, FUTEX_OP_CMP_GT, 1}) = 1
futex(0x1e45218, FUTEX_WAKE_PRIVATE, 1) = 1
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
ioctl(7, 0x80044121, 0xbebd764c) = 0
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
gettimeofday({1376379565, 54761}, NULL) = 0
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
open("/usr/local/lib/python2.7/dist-packages/pi-0.1.0-py2.7.egg/static/sounds/pi-listening.wav", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
open("/usr/local/lib/python2.7/dist-packages/pi-0.1.0-py2.7.egg/static/sounds/pi-listening.wav", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
lstat64("/tmp/tmpkTS2Fwpi.wav", 0xbebd73a0) = -1 ENOENT (No such file or directory)
socketpair(PF_FILE, SOCK_STREAM, 0, [19, 20]) = 0
fcntl64(19, F_SETFL, O_RDONLY|O_NONBLOCK) = 0
fcntl64(20, F_SETFL, O_RDONLY|O_NONBLOCK) = 0
brk(0x1f20000) = 0x1f20000
socketpair(PF_FILE, SOCK_STREAM, 0, [21, 22]) = 0
fcntl64(21, F_SETFL, O_RDONLY|O_NONBLOCK) = 0
fcntl64(22, F_SETFL, O_RDONLY|O_NONBLOCK) = 0
write(1, "Bossjones Note: Technically we'r"..., 97) = 97
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
stat64("/usr/share/alsa/alsa.conf", {st_mode=S_IFREG|0644, st_size=9184, ...}) = 0
open("/dev/snd/controlC1", O_RDONLY|O_CLOEXEC) = 23
fcntl64(23, F_SETFD, FD_CLOEXEC) = 0
ioctl(23, UI_DEV_CREATE, 0xbebd6dd4) = 0
close(23) = 0
open("/dev/snd/controlC1", O_RDWR|O_CLOEXEC) = 23
fcntl64(23, F_SETFD, FD_CLOEXEC) = 0
ioctl(23, USBDEVFS_CONTROL or USBDEVFS_CONTROL32, 0xbebd6f74) = 0
ioctl(23, 0x40045532, 0xbebd6fac) = 0
open("/dev/snd/pcmC1D0c", O_RDWR|O_NONBLOCK|O_CLOEXEC) = -1 EBUSY (Device or resource busy)
close(23) = 0
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
open("/tmp/tmpkTS2Fwpi.wav", O_WRONLY|O_CREAT|O_TRUNC|O_LARGEFILE, 0666) = 23
fstat64(23, {st_mode=S_IFREG|0644, st_size=0, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb6f6f000
_llseek(23, 0, [0], SEEK_SET) = 0
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
stat64("/usr/share/alsa/alsa.conf", {st_mode=S_IFREG|0644, st_size=9184, ...}) = 0
open("/dev/snd/controlC1", O_RDONLY|O_CLOEXEC) = 24
fcntl64(24, F_SETFD, FD_CLOEXEC) = 0
ioctl(24, UI_DEV_CREATE, 0xbebd6dd4) = 0
close(24) = 0
open("/dev/snd/controlC1", O_RDWR|O_CLOEXEC) = 24
fcntl64(24, F_SETFD, FD_CLOEXEC) = 0
ioctl(24, USBDEVFS_CONTROL or USBDEVFS_CONTROL32, 0xbebd6f74) = 0
ioctl(24, 0x40045532, 0xbebd6fac) = 0
open("/dev/snd/pcmC1D0c", O_RDWR|O_NONBLOCK|O_CLOEXEC) = -1 EBUSY (Device or resource busy)
close(24) = 0
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(1, " * Listening closely...\n", 24) = 24
clock_gettime(CLOCK_MONOTONIC, {355220, 267713756}) = 0
clock_gettime(CLOCK_MONOTONIC, {355220, 268557726}) = 0
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 1 ([{fd=3, revents=POLLIN}])
read(3, "-\0\0\0\0\0\0\0", 16) = 8
clock_gettime(CLOCK_MONOTONIC, {355220, 273415554}) = 0
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
read(3, 0xbebd828c, 16) = -1 EAGAIN (Resource temporarily unavailable)
clock_gettime(CLOCK_MONOTONIC, {355220, 277294417}) = 0
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
clock_gettime(CLOCK_MONOTONIC, {355220, 280380308}) = 0
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
clock_gettime(CLOCK_MONOTONIC, {355220, 282305240}) = 0
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
clock_gettime(CLOCK_MONOTONIC, {355220, 284684156}) = 0
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
clock_gettime(CLOCK_MONOTONIC, {355220, 286915077}) = 0
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
clock_gettime(CLOCK_MONOTONIC, {355220, 290111964}) = 0
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
clock_gettime(CLOCK_MONOTONIC, {355220, 291641910}) = 0
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
clock_gettime(CLOCK_MONOTONIC, {355220, 293437847}) = 0
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
clock_gettime(CLOCK_MONOTONIC, {355220, 295553772}) = 0
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 10705) = 0 (Timeout)
clock_gettime(CLOCK_MONOTONIC, {355231, 13213798}) = 0
write(1, " # cancel False False\n", 22) = 22
write(1, " * Not a word in the past 10 sec"..., 49) = 49
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
close(23) = 0
munmap(0xb6f6f000, 4096) = 0
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
gettimeofday({1376379576, 186258}, NULL) = 0
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
open("/usr/local/lib/python2.7/dist-packages/pi-0.1.0-py2.7.egg/static/sounds/pi-cancel.wav", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
open("/usr/local/lib/python2.7/dist-packages/pi-0.1.0-py2.7.egg/static/sounds/pi-cancel.wav", O_RDONLY|O_LARGEFILE) = -1 ENOENT (No such file or directory)
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
ioctl(7, 0x80044121, 0xbebd7ac4) = -1 EPIPE (Broken pipe)
futex(0xe78524, FUTEX_WAKE_OP_PRIVATE, 1, 1, 0xe78520, {FUTEX_OP_SET, 0, FUTEX_OP_CMP_GT, 1}) = 1
futex(0xe78500, FUTEX_WAKE_PRIVATE, 1) = 1
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
futex(0x1b82fec, FUTEX_WAKE_OP_PRIVATE, 1, 1, 0x1b82fe8, {FUTEX_OP_SET, 0, FUTEX_OP_CMP_GT, 1}) = 1
futex(0x1ac5618, FUTEX_WAKE_PRIVATE, 1) = 1
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
write(3, "\1\0\0\0\0\0\0\0", 8) = 8
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 1 ([{fd=3, revents=POLLIN}])
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 1 ([{fd=3, revents=POLLIN}])
read(3, "*\0\0\0\0\0\0\0", 16) = 8
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
read(3, 0xbebd828c, 16) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, 0) = 0 (Timeout)
poll([{fd=3, events=POLLIN}, {fd=6, events=POLLIN}], 2, -1^C <unfinished ...>
Process 12416 detached
Question: What can I do to make this work?
Here is the python code.
Listener.py:
import pi
from pi.becore import ScarlettConfig
from recorder import Recorder
from brain import Brain
import os
import json
import tempfile
#import sys
import pygtk
pygtk.require('2.0')
import gtk
import gobject
import pygst
pygst.require('0.10')
gobject.threads_init()
import gst
scarlett_config=ScarlettConfig()
class Listener:
def __init__(self, gobject, gst):
self.failed = 0
self.pipeline = gst.parse_launch(' ! '.join(['alsasrc device=' + scarlett_config.gimmie('audio_input_device'),
'queue',
'audioconvert',
'audioresample',
'queue',
'vader name=vader auto-threshold=true',
'pocketsphinx lm=' + scarlett_config.gimmie('LM') + ' dict=' + scarlett_config.gimmie('DICT') + ' hmm=' + scarlett_config.gimmie('HMM') + ' name=listener',
'fakesink dump=1']))
listener = self.pipeline.get_by_name('listener')
listener.connect('result', self.__result__)
listener.set_property('configured', True)
print "KEYWORDS WE'RE LOOKING FOR: " + scarlett_config.gimmie('ourkeywords')
bus = self.pipeline.get_bus()
bus.add_signal_watch()
bus.connect('message::application', self.__application_message__)
self.pipeline.set_state(gst.STATE_PLAYING)
def result(self, hyp, uttid):
if hyp in scarlett_config.gimmie('ourkeywords'):
self.failed = 0
self.listen()
else:
self.failed += 1
if self.failed > 4:
pi.speak("" + scarlett_config.gimmie('scarlett_owner') + ", if you need me, just say my name.")
self.failed = 0
def listen(self):
self.pipeline.set_state(gst.STATE_PAUSED)
pi.play('pi-listening')
Recorder(self)
def cancel_listening(self):
pi.play('pi-cancel')
self.pipeline.set_state(gst.STATE_PLAYING)
###[ ........MUSIC SUFF HERE........ ]
def __result__(self, listener, text, uttid):
struct = gst.Structure('result')
struct.set_value('hyp', text)
struct.set_value('uttid', uttid)
listener.post_message(gst.message_new_application(listener, struct))
def __application_message__(self, bus, msg):
msgtype = msg.structure.get_name()
if msgtype == 'result':
self.result(msg.structure['hyp'], msg.structure['uttid'])
Here is the recorder.py:
import pi
from pi.becore import ScarlettConfig
import os
import tempfile
import pygtk
pygtk.require('2.0')
import gtk
import gobject
import pygst
pygst.require('0.10')
gobject.threads_init()
import gst
scarlett_config=ScarlettConfig()
class Recorder:
def __init__(self, listener):
self.listener = listener
self.started = False
self.finished = False
self.recording = tempfile.mktemp(suffix='pi.wav')
self.pipeline = gst.parse_launch(' ! '.join(['alsasrc device=' + scarlett_config.gimmie('audio_input_device'),
'queue',
'audioconvert',
'queue',
'audioresample',
'queue',
'vader name=vader auto-threshold=false',
'fakesink dump=1']))
print "Bossjones Note: What is the current PIPLINE state BEFORE we're recording" + self.pipeline.get_state()
self.recorder = gst.parse_launch(' ! '.join(['alsasrc device=' + scarlett_config.gimmie('audio_input_device'),
'queue',
'audioconvert',
'audioresample',
'audio/x-raw-int,rate=16000,width=16,channels=1,endianness=(int)1234',
'wavenc',
'filesink location=' + self.recording]))
print "Bossjones Note: Technically we're suppose to be recording to this location: " + self.recording
vader = self.pipeline.get_by_name('vader')
vader.connect('vader_start', self.__start__)
vader.connect('vader_stop', self.__stop__)
bus = self.pipeline.get_bus()
bus.add_signal_watch()
bus.connect('message::application', self.__application_message__)
self.pipeline.set_state(gst.STATE_PLAYING)
self.recorder.set_state(gst.STATE_PLAYING)
print " * Listening closely..."
gobject.timeout_add_seconds(10, self.cancel)
def start(self):
self.started = True
print " * Recording..."
def stop(self):
print " * (silence)"
gobject.timeout_add_seconds(1, self.stop_now)
def stop_now(self):
print " # stop_now"
if self.finished == True:
self.listener.cancel_listening()
return
self.finished = True
print " * Stored recording to ", self.recording
self.pipeline.set_state(gst.STATE_NULL)
self.recorder.set_state(gst.STATE_NULL)
print " * Converting to FLAC..."
os.system("ffmpeg -i %s -y %s" % (self.recording, self.recording))
#os.unlink(self.recording)
os.system("sox %s %s.final.wav noisered %s/static/noise.prof 0.21" % (self.recording, self.recording, pi.PWD))
os.system("flac -f --best --sample-rate 16000 -o %s.flac %s.final.wav 2>/dev/null" % (self.recording, self.recording))
os.unlink(self.recording + ".final.wav")
print " * Done."
self.listener.answer(self.recording + '.flac')
def cancel(self):
print " # cancel", self.finished, self.started
if self.finished == True:
print " # cancel - noop"
return
if self.started == False:
self.finished = True
print " * Not a word in the past 10 seconds, cancelling"
self.pipeline.set_state(gst.STATE_NULL)
self.recorder.set_state(gst.STATE_NULL)
self.listener.cancel_listening()
def __start__(self, vader, arg0):
print " # vader:start"
struct = gst.Structure('vader_start')
struct.set_value('arg0', arg0)
vader.post_message(gst.message_new_application(vader, struct))
def __stop__(self, vader, arg0):
print " # vader:stop"
struct = gst.Structure('vader_stop')
struct.set_value('arg0', arg0)
vader.post_message(gst.message_new_application(vader, struct))
def __application_message__(self, bus, msg):
msgtype = msg.structure.get_name()
if msgtype == 'vader_stop':
self.stop()
elif msgtype == 'vader_start':
self.start()
Thoughts on the best way to debug this?
Thanks.
回答1:
So, as a launch-line, you want something like this:
gst-launch alsasrc device=hw:1 ! queue ! audioconvert ! audioresample ! "audio/x-raw-int, rate=16000, width=16, depth=16, channels=1" ! tee name=t ! queue ! audioresample ! "audio/x-raw-int, rate=8000" ! fvader name=vader auto-threshold=true ! pocketsphinx lm=/home/pi/dev/scarlettPi/config/speech/lm/scarlett.lm dict=/home/pi/dev/scarlettPi/config/speech/dict/scarlett.dic hmm=/usr/local/share/pocketsphinx/model/hmm/en_US/hub4wsj_sc_8k name=listener ! fakesink dump=1 t. ! valve drop=0 ! queue ! wavenc ! filesink location=test.wav async=0
The idea is that one alsasrc represents your microphone, and since this can be an exclusive access, you should not start another alsasrc to access the same device. This also makes for better code, since you want to record from the same device you are doing speech-detection from (as I understand), and by using the same source you are guaranteed that this will be the case.
Now, in order to do this in python, you should probably set up the pipeline "properly" rather than doing parse-launch, meaning you have to instantiate each element:
self.recording_valve = gst.element_factory_make('valve')
Add them to your pipeline:
self.pipeline.add (self.recording_valve)
And then link them:
self.recording_valve.link (self.next_element)
...which is what parse-launch does internally, however, in your start and stop recording, you can now do:
self.recording_valve.set_property('drop', False)
To start recording, and
self.recording_valve.set_property('drop', True)
To stop.
(Remember to set drop to True initially, since it is False by default)
The last piece you will need to put all this together is to know about the tee, and its request-pads. It can have any number of src-pads, and you can do the following to link it:
self.tee.get_request_pad('src%d').link(self.recording_valve_queue.get_pad('sink'))
Basically, you request a srcpad from the Tee, and link it to the sinkpad of the valve. You will need to do this twice for each of the tee's branches.
Get that all up and running, and you should have something that works.
来源：https://stackoverflow.com/questions/18220129/pocketsphinx-gstreamer-race-condition-pocketsphinx-cant-listen-to-audio-re