Archived:How to play a tone sound using PySymbian

Article Metadata

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Tested with

Devices(s): Nokia N95, Nokia E90

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Compatibility

Platform(s): S60 1st Edition, S60 2nd Edition, S60 3rd Edition

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Platform Security

Capabilities: )

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Article

Keywords: audio

Created: cyke64 (31 Mar 2007)

Last edited: hamishwillee (18 Sep 2012)

Overview

This snippet shows how to play a tone in Python.

Source code

from struct import pack
from math import sin, pi
import e32, audio
 
 
#Function for generating a tone file
def au_file(name="out.au", freq=400, length=2, A=0.5):
	f = open(name, 'wb')
	f.write('.snd')
	f.write(pack('>5L', 24, -1, 2, 8000, 1))
	T = 8000. / freq
	for i in range(length * 8000):
		angle = 2 * pi * i / T
		val = pack('b', A * sin(angle) * 127)
		f.write(val)
	f.close()
 
#Function for playing the tone file
def tone(freq=440, duration=1000, volume=0.5):
	#Read the temporary file
	f = open("D:\\out.au", 'wb')
	f.write('.snd' + pack('>5L', 24, 8 * duration, 2, 8000, 1))
	for i in range(duration * 8):
		sin_i = sin(i * 2 * pi * freq / 8000) #Sine wave
		f.write(pack('b', volume * 127 * sin_i))
	f.close()
	#Play the file
	s = audio.Sound.open("D:\\out.au")
	s.play()
	while s.state() == 2: #Playing
		e32.ao_yield()
	s.close()
 
au_file()
tone()

Postconditions

A sound with the given properties is played.