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(3alleg5).  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:

       • 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.

       • frag_samples - The size of a fragment in samples.  See note and explanation below.

       • freq - The frequency, in Hertz.

       • depth - Must be one of the values listed for ALLEGRO_AUDIO_DEPTH(3alleg5).

       • chan_conf - Must be one of the values listed for ALLEGRO_CHANNEL_CONF(3alleg5).

       A sample that is referred to by the frag_samples parameter refers to  a  sequence  channel
       intensities.   E.g.  if you’re making a stereo stream with the frag_samples set to 4, then
       the layout of the data in the fragment will be:

              LRLRLRLR

       Where L and R are the intensities for the left and right channels respectively.  A  single
       sample, then, refers to the LR pair in this example.

       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(3alleg5) before the audio system is shut down.