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al_create_audio_stream(3)                            al_create_audio_stream(3)

NAME
       al_create_audio_stream - Allegro 5 API

SYNOPSIS

              #include <allegro5/allegro_audio.h>

              ALLEGRO_AUDIO_STREAM *al_create_audio_stream(size_t fragment_count,
                 unsigned int frag_samples, unsigned int freq, ALLEGRO_AUDIO_DEPTH depth,
                 ALLEGRO_CHANNEL_CONF chan_conf)

DESCRIPTION
       Creates an ALLEGRO_AUDIO_STREAM(3).  The stream will be set to play by
       default.  It will feed audio data from a buffer, which is split into a
       number of fragments.

       Parameters:

       o fragment_count - How many fragments to use for the audio stream.
         Usually only two fragments are required - splitting the audio buffer
         in two halves.  But it means that the only time when new data can be
         supplied is whenever one half has finished playing.  When using many
         fragments, you usually will use fewer samples for one, so there
         always will be (small) fragments available to be filled with new
         data.

       o frag_samples - The size of a fragment in samples.  See note below.

       o freq - The frequency, in Hertz.

       o depth - Must be one of the values listed for ALLEGRO_AUDIO_DEPTH(3).

       o chan_conf - Must be one of the values listed for
         ALLEGRO_CHANNEL_CONF(3).

       The choice of fragment_count, frag_samples and freq directly influences
       the audio delay.  The delay in seconds can be expressed as:

              delay = fragment_count * frag_samples / freq

       This is only the delay due to Allegro's streaming, there may be
       additional delay caused by sound drivers and/or hardware.

              Note: If you know the fragment size in bytes, you can get the
              size in samples like this:

                     sample_size = al_get_channel_count(chan_conf) * al_get_audio_depth_size(depth);
                     samples = bytes_per_fragment / sample_size;

              The size of the complete buffer is:

                     buffer_size = bytes_per_fragment * fragment_count

              Note: unlike many Allegro objects, audio streams are not
              implicitly destroyed when Allegro is shut down.  You must
              destroy them manually with al_destroy_audio_stream(3) before the
              audio system is shut down.

Allegro reference manual                             al_create_audio_stream(3)