code gets all gibberishy in the message itself attatch the .py file(s) to the message
________________________________ From: Jerzy Jalocha N <jjalo...@gmail.com> To: pygame-users <pygame-users@seul.org> Sent: Monday, July 20, 2009 8:44:45 AM Subject: [pygame] noob questions about creating and playing sounds Hi, I am starting to experiment with Pygame and how to generate sounds and play them back. Here is a code snippet, the full (working) code is below. def play_maxtime(sound, duration): sound.play(loops=-1, maxtime=duration) pygame.time.delay(duration) I have a few questions about this: * Why is it that play_maxtime doesn't work without the time.delay? When I remove the delay line, no sound is played, despite the use of the maxtime argument. * Why does this sound so ugly? This method (and play_loops below) produces a terrible rattle, regardless the sample-rate. (Note, that I am using 16 bit, which should produce at least decent quality. And it is not clipping.) * Anyone knows how to create the sound in real-time, and feed it to the sound card? For example, make the frequency depend on the mouse position. Since it is quite difficult to find information and examples about how to create and play back sounds in Python and Pygame, I am posting the complete working example below, for reference. Maybe other noobs might find it useful. This code was adapted from a post on other mailing list: http://mail.python.org/pipermail/tutor/2009-March/067724.html import numpy import pygame # Create the sound wave in the required bit-rate. def sine_array(freq, amplitude, sample_rate): wavelength = sample_rate / freq omega = 2 * numpy.pi / wavelength xvalues = numpy.arange(wavelength) * omega return numpy.int16(amplitude * numpy.sin(xvalues)) # Two different methods for playing the sound. def play_maxtime(sound, duration): sound.play(loops=-1, maxtime=duration) pygame.time.delay(duration) def play_loops(sound, duration): sound.play(loops=-1) pygame.time.delay(duration) sound.stop() # Initialize PyGame & PyGame sound system. sample_rate, bit_rate, channels = 22050, -16, 1 pygame.mixer.pre_init(sample_rate, bit_rate, channels) pygame.init() sample_rate, bit_rate, channels = pygame.mixer.get_init() assert bit_rate == -16 # sine_array only implements 16 bit signed pygame.sndarray.use_arraytype('numpy') # Create a sound array, and convert it to a Sound object. sound_array = sine_array(440, 20000, sample_rate) sound = pygame.sndarray.make_sound(sound_array) # Play the sound using two different methods. duration = 2000 play_maxtime(sound, duration) pygame.time.delay(duration) play_loops(sound, duration)
