#!/usr/bin/python3
# -*- coding: utf-8 -*-
from pyaudio import PyAudio, paInt16 
import numpy as np 
from datetime import datetime 
import wave
class recoder:
  NUM_SAMPLES = 2000   #pyaudio内置缓冲大小
  SAMPLING_RATE = 8000  #取样频率
  LEVEL = 500     #声音保存的阈值
  COUNT_NUM = 20   #NUM_SAMPLES个取样之内出现COUNT_NUM个大于LEVEL的取样则记录声音
  SAVE_LENGTH = 8     #声音记录的最小长度：SAVE_LENGTH * NUM_SAMPLES 个取样
  TIME_COUNT = 60   #录音时间，单位s
  Voice_String = []
  def savewav(self,filename):
    wf = wave.open(filename, 'wb') 
    wf.setnchannels(1) 
    wf.setsampwidth(2) 
    wf.setframerate(self.SAMPLING_RATE) 
    wf.writeframes(np.array(self.Voice_String).tostring()) 
    # wf.writeframes(self.Voice_String.decode())
    wf.close() 
  def recoder(self):
    pa = PyAudio() 
    stream = pa.open(format=paInt16, channels=1, rate=self.SAMPLING_RATE, input=True, 
      frames_per_buffer=self.NUM_SAMPLES) 
    save_count = 0 
    save_buffer = [] 
    time_count = self.TIME_COUNT
    while True:
      time_count -= 1
      # print time_count
      # 读入NUM_SAMPLES个取样
      string_audio_data = stream.read(self.NUM_SAMPLES) 
      # 将读入的数据转换为数组
      audio_data = np.fromstring(string_audio_data, dtype=np.short)
      # 计算大于LEVEL的取样的个数
      large_sample_count = np.sum( audio_data > self.LEVEL )
      print(np.max(audio_data))
      # 如果个数大于COUNT_NUM，则至少保存SAVE_LENGTH个块
      if large_sample_count > self.COUNT_NUM:
        save_count = self.SAVE_LENGTH 
      else: 
        save_count -= 1
      if save_count < 0:
        save_count = 0 
      if save_count > 0 : 
      # 将要保存的数据存放到save_buffer中
        #print save_count > 0 and time_count >0
        save_buffer.append( string_audio_data ) 
      else: 
      #print save_buffer
      # 将save_buffer中的数据写入WAV文件，WAV文件的文件名是保存的时刻
        #print "debug"
        if len(save_buffer) > 0 : 
          self.Voice_String = save_buffer
          save_buffer = [] 
          print("Recode a piece of voice successfully!")
          return True
      if time_count==0: 
        if len(save_buffer)>0:
          self.Voice_String = save_buffer
          save_buffer = [] 
          print("Recode a piece of voice successfully!")
          return True
        else:
          return False
if __name__ == "__main__":
  r = recoder()
  r.recoder()
  r.savewav("test.wav")