sound synchronization in C or Python

Question

Hi, I'd like to play a sound and have some way of reliably telling how much of it has thus far been played. I've looked at several sound libraries but they are all horribly underdocumented and only seem to export a "PlaySound, no questions asked" routine.

I.e, I want this:

a = Sound(filename)  
PlaySound(a);  
while true:  
    print a.miliseconds_elapsed, a.length  
    sleep(1)  

C, C++ or Python solutions preferred. Thank you.

Answer 1

This is most likely going to be both hardware-dependent (sound card etc) and OS-dependent (size of buffers used by OS etc).

Maybe it would help if you said a little more about what you're really trying to achieve and also whether we can make any assumptions about what hardware and OS this will run on ?

One possible solution: assume that the sound starts playing more or less immediately and then use a reasonably accurate timer to determine how much of the sound has played (since it will have a known, fixed sample rate).

Answer 2

I use BASS Audio Library (http://www.un4seen.com/)

BASS is an audio library for use in Windows and Mac OSX software. Its purpose is to provide developers with powerful and efficient sample, stream (MP3, MP2, MP1, OGG, WAV, AIFF, custom generated, and more via add-ons), MOD music (XM, IT, S3M, MOD, MTM, UMX), MO3 music (MP3/OGG compressed MODs), and recording functions. All in a tiny DLL, under 100KB in size.*

A C program using BASS is as simple as

HSTREAM str;
BASS_Init(-1,44100,0,0,NULL);
BASS_Start();
str=BASS_StreamCreateFile(FALSE,filename,0,0,0);
BASS_ChannelPlay(str,FALSE);
while (BASS_ChannelIsActive(str)==BASS_ACTIVE_PLAYING) {
  pos=BASS_ChannelGetPosition(str,BASS_POS_BYTE);
}
BASS_Stop();
BASS_Free();

Answer 3

Hi, I'm also looking for a nice Audiolibrary, where i can directly write on the Soundcards Buffer. I didn't have time yet to have a look at it myself, but pyAudio looks pretty nice. If you scroll down on the page you see an example similar like yours.

With help of the buffersize, number of channels and sample rate you can easily calculate the time each loop-step lasts and print it out.