概述：这是对我上一个问题（here）的跟进。我很快就会发布一个完整的答案。我能够通过Gstreamer通过我的PS3 Eye in Python识别audiophinx来识别音频输入。通过指定正确的alsa设备（在我的情况下为hw：1）。
问题我的下一个问题似乎涉及一个微小的竞争条件，涉及我的麦克风已经在使用并需要能够录制内容。
想象一下：
现在好像，当我开始第3步时，麦克风再次停止工作。我运行了一些冗长的选项，试图弄清楚发生了什么，但检查我的/ tmp /目录告诉我一切：
pi@scarlettpi ~ $ ls -lta /tmp/ | grep wav
-rw-r--r-- 1 pi pi 0 Aug 13 20:57 fsdgjdspi.wav
pi@scarlettpi ~ $
文件大小为0字节。没有记录任何内容。
确认我通过strace运行过程并确认我怀疑的内容：
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
问题：我该怎么做才能使这项工作？
这是python代码。
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'])
这是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()
关于调试此方法的最佳方法的想法？
感谢。
答案 0 :(得分：1)
所以，作为一个发射线，你需要这样的东西：
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
这个想法是一个alsasrc代表你的麦克风，因为这可以是一个独占访问，你不应该启动另一个alsasrc来访问同一个设备。这也可以提供更好的代码，因为你想要从你正在进行语音检测的同一设备上录制（据我所知），并且使用相同的源代码，你可以保证会出现这种情况。
现在，为了在python中执行此操作，您应该设置管道 “正确”而不是进行解析启动，这意味着你必须实例化每个元素：
self.recording_valve = gst.element_factory_make('valve')
将它们添加到您的管道中：
self.pipeline.add (self.recording_valve)
然后链接他们：
self.recording_valve.link (self.next_element)
...这就是内部解析启动的功能，但是，在开始和停止录制时，您现在可以执行以下操作：
self.recording_valve.set_property('drop', False)
开始录制，
self.recording_valve.set_property('drop', True)
停止。
（记得最初设置drop为True，因为默认为False）
您需要将所有这些放在一起的最后一块是了解发球台及其请求垫。它可以有任意数量的src-pad，您可以执行以下操作来链接它：
self.tee.get_request_pad('src%d').link(self.recording_valve_queue.get_pad('sink'))
基本上，您从Tee请求srcpad，并将其链接到阀门的接收器。你需要为每个发球台的两个分支做两次。
全部启动并运行，你应该有一些有用的东西。