我正在构建一个用于处理生态记录的小型音频GUI。我希望能够播放一个文件，暂停它，然后从暂停的地方重新播放它。我可以让它播放，暂停(停止)，但当我再次点击播放时，它会重新开始音频，而不是从它离开的地方捡起。Pyaudio有回调函数，这就是我想要实现的(参见这里的工作示例)。那个例子就是我想要的，除了这个例子有键盘。在while语句中控制播放/暂停的监听器行，我需要从tkinter实现播放/暂停按钮功能。我还设置了回放线程，这样GUI就不会冻结按钮，这对我来说增加了一些复杂性(我是一个自学python的生态学家，不是计算机科学家!)。我已经使用threading.Event()作为控制流线程的一种方式，但我认为这只会增加额外的复杂性，并使我从暂停位置重新启动的问题相同。
最终我也想拉出帧数/时间文件暂停时，并绘制在tkinter画布/matplot图上的进度条-我的一部分说pyaudio .get_time()内嵌入回调可能能够帮助这(我认为它返回系统时间)。
下面是一个最小的例子，我可以得到一个gui工作与我在哪里。
import tkinter as tk
from tkinter import ttk
import wave
import pyaudio
import threading
import time
import numpy as np
import datetime
from matplotlib.figure import Figure
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
# gui class
class basic_player():
def __init__(self, root):
# BUILD ROOT
self.root = root
root.title('Playback')
self.audio_file = 'C:/Data/Acoustics/Test/5D8CA5E8.WAV'
self.frame_plot()
self.frame_buttons()
# class globals
self.stream_paused = False
def frame_plot(self):
'''Frame for file plot'''
self.frame_plot = ttk.Frame(self.root, height = 100, width = 500)
self.frame_plot.grid(column = 0, row = 0, sticky = 'nsew', columnspan = 2)
self.frame_plot.grid_propagate(False)
# plot file
self.func_plot_fileplot()
def func_plot_fileplot(self):
'''Plot the main audiofile'''
# create figure to contain plot
# get frame size parameters (update frame parameters first)
self.frame_plot.update()
dpi = self.root.winfo_fpixels('1i')
plotwidth = self.frame_plot.winfo_width() / dpi
plotheight = self.frame_plot.winfo_height() / dpi
# create plot
plot_figure_fileplot_main = Figure(figsize = (plotwidth, plotheight),
dpi = dpi, frameon = False, tight_layout = True)
# get data
with wave.open(self.audio_file, mode = 'rb') as wf:
infile_audio_bytes = wf.readframes(wf.getnframes())
data = np.frombuffer(infile_audio_bytes, dtype = np.int16)
# plot x labels
lst_x_ticks = list(range(0, wf.getnframes(), int(wf.getnframes() / 8))) + [wf.getnframes()]
lst_x_label = [str(datetime.timedelta(seconds = int(sample / wf.getframerate()))) for sample in lst_x_ticks]
# add subplot
plot_figure_fileplot = plot_figure_fileplot_main.add_subplot(111)
plot_figure_fileplot.plot(data, linewidth = 0.25)
# adjust subplot visuals
plot_figure_fileplot.set_xmargin(0)
plot_figure_fileplot.yaxis.set_visible(False)
plot_figure_fileplot.spines['top'].set_visible(False)
plot_figure_fileplot.spines['right'].set_visible(False)
plot_figure_fileplot.spines['left'].set_visible(False)
# labels for plot x axis
plot_figure_fileplot.set_xticks(lst_x_ticks) # set x labels to existing to make sure they find the right spot
plot_figure_fileplot.set_xticklabels(lst_x_label, size = 8)
#create tkinter canvas
self.canvas_plot_figure_main = FigureCanvasTkAgg(plot_figure_fileplot_main, master = self.frame_plot)
self.canvas_plot_figure_main.draw()
#place canvas on tkinter window
self.canvas_plot_figure_main.get_tk_widget().grid(sticky = 'nsew')
def frame_buttons(self):
'''The main frame for the initial window'''
frame_buttons = ttk.Frame(self.root, width = 100)
frame_buttons.grid(column = 0, row = 1, sticky = 'nsew')
btn_play = tk.Button(frame_buttons,
text = 'PLAY',
command = self.buttons_command_play,
state = 'normal',
width = 10)
btn_play.grid(column = 0, row = 0, sticky = 'nsew', padx = 10, pady = 10)
btn_pause = tk.Button(frame_buttons,
text = 'PAUSE',
command = self.buttons_command_playback_pause,
state = 'normal',
width = 10)
btn_pause.grid(column = 1, row = 0, sticky = 'nsew', padx = 10, pady = 10)
def buttons_command_play(self):
''' send play audio function to thread '''
self.stream_paused = False
self.stream_thread = threading.Thread(target = self.play_audio)
self.stream_thread.start()
def play_audio(self):
'''Play audio'''
if self.stream_paused: # this doesnt work.
self.stream.start_stream()
else:
# open file
wf = wave.open(self.audio_file, mode = 'rb')
# instantiate pyaudio
self.pyaudio_init = pyaudio.PyAudio()
# define callback
def callback(in_data, frame_count, time_info, status):
data = wf.readframes(frame_count)
return (data, pyaudio.paContinue)
# open stream using callback
self.stream = self.pyaudio_init.open(format=self.pyaudio_init.get_format_from_width(wf.getsampwidth()),
input = False,
channels=wf.getnchannels(),
rate=wf.getframerate(),
output=True,
stream_callback=callback)
self.stream.start_stream()
# start the stream
while self.stream.is_active() and not self.stream_paused:
# this is where the control event needs to work i believe
time.sleep(0.1)
# stop stream
self.stream.stop_stream()
self.stream.close()
wf.close()
def buttons_command_playback_pause(self):
''' Pause the audio '''
if not self.stream_paused:
self.stream_paused = True
else:
pass
## SETUP AND RUN
root = tk.Tk()
basic_player(root)
root.mainloop()
这里不需要stream_callback。您可以创建一个新线程，并在循环中运行stream.write()。
要暂停音频，设置一个标志，并在循环中添加一个条件。仅当暂停条件为False
时才写入流。下面是一个例子。
import tkinter as tk
import wave
import pyaudio
import threading
class SamplePlayer:
def __init__(self, master):
frame = tk.Frame(master=master)
frame.pack(expand=True, fill="both")
self.current_lbl = tk.Label(master=frame, text="0/0")
self.current_lbl.pack()
self.pause_btn = tk.Button(master=frame, text="Pause", command=self.pause)
self.pause_btn.pack()
self.play_btn = tk.Button(master=frame, text="Play", command=self.play)
self.play_btn.pack()
self.file = r"sample_wavfile.wav"
self.paused = True
self.playing = False
self.audio_length = 0
self.current_sec = 0
self.after_id = None
def start_playing(self):
p = pyaudio.PyAudio()
chunk = 1024
with wave.open(self.file, "rb") as wf:
self.audio_length = wf.getnframes() / float(wf.getframerate())
stream = p.open(format =
p.get_format_from_width(wf.getsampwidth()),
channels = wf.getnchannels(),
rate = wf.getframerate(),
output = True)
data = wf.readframes(chunk)
chunk_total = 0
while data != b"" and self.playing:
if not self.paused:
chunk_total += chunk
stream.write(data)
data = wf.readframes(chunk)
self.current_sec = chunk_total/wf.getframerate()
self.playing=False
stream.close()
p.terminate()
def pause(self):
self.paused = True
if self.after_id:
self.current_lbl.after_cancel(self.after_id)
self.after_id = None
def play(self):
if not self.playing:
self.playing = True
threading.Thread(target=self.start_playing, daemon=True).start()
if self.after_id is None:
self.update_lbl()
self.paused = False
def stop(self):
self.playing = False
if self.after_id:
self.current_lbl.after_cancel(self.after_id)
self.after_id = None
def update_lbl(self):
self.current_lbl.config(text=f"{self.current_sec}/{self.audio_length}")
self.after_id = self.current_lbl.after(5, self.update_lbl)
def handle_close():
player.stop()
root.destroy()
## SETUP AND RUN
root = tk.Tk()
player = SamplePlayer(root)
root.protocol("WM_DELETE_WINDOW", handle_close)
root.mainloop()
这个答案与@Art的答案相同，但我删除了self.after_id变量以简化逻辑:
import tkinter as tk
import threading
import pyaudio
import wave
import time
class SamplePlayer:
def __init__(self, master):
frame = tk.Frame(master=master)
frame.pack(expand=True, fill="both")
self.current_lbl = tk.Label(master=frame, text="0/0")
self.current_lbl.pack()
self.pause_btn = tk.Button(master=frame, text="Pause", command=self.pause)
self.pause_btn.pack()
self.play_btn = tk.Button(master=frame, text="Play", command=self.play)
self.play_btn.pack()
# If you aren't going to use ``s there is no need for the
# "r" before the start of the string
self.file = r"sample_wavfile.wav"
self.paused = True
self.playing = False
self.audio_length = 0
self.current_sec = 0
def start_playing(self):
""" # I don't have `pyaudio` so I used this to test my answer:
self.audio_length = 200
while self.playing:
if not self.paused:
self.current_sec += 1
time.sleep(1)
return None
# """
p = pyaudio.PyAudio()
chunk = 1024
with wave.open(self.file, "rb") as wf:
self.audio_length = wf.getnframes() / float(wf.getframerate())
stream = p.open(format=p.get_format_from_width(wf.getsampwidth()),
channels=wf.getnchannels(),
rate=wf.getframerate(),
output=True)
data = wf.readframes(chunk)
chunk_total = 0
while data != b"" and self.playing:
if self.paused:
time.sleep(0.1)
else:
chunk_total += chunk
stream.write(data)
data = wf.readframes(chunk)
self.current_sec = chunk_total/wf.getframerate()
self.playing = False
stream.close()
p.terminate()
def pause(self):
self.paused = True
def play(self):
if not self.playing:
self.playing = True
threading.Thread(target=self.start_playing, daemon=True).start()
if self.paused:
self.paused = False
self.update_lbl()
def stop(self):
self.playing = False
def update_lbl(self):
if self.playing and (not self.paused):
self.current_lbl.config(text=f"{self.current_sec}/{self.audio_length}")
# There is no need to update the label more than 10 times a second.
# It changes once per second anyways.
self.current_lbl.after(100, self.update_lbl)
def handle_close():
player.stop()
root.destroy()
## SETUP AND RUN
root = tk.Tk()
player = SamplePlayer(root)
root.protocol("WM_DELETE_WINDOW", handle_close)
root.mainloop()
if self.playing and (not self.paused)添加到调用.after的代码中，则不需要self.after_id变量。在本例中是update_lbl方法。