1al_create_audio_stream(3)                            al_create_audio_stream(3)
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NAME

6       al_create_audio_stream - Allegro 5 API
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SYNOPSIS

9              #include <allegro5/allegro_audio.h>
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11              ALLEGRO_AUDIO_STREAM *al_create_audio_stream(size_t fragment_count,
12                 unsigned int frag_samples, unsigned int freq, ALLEGRO_AUDIO_DEPTH depth,
13                 ALLEGRO_CHANNEL_CONF chan_conf)
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DESCRIPTION

16       Creates  an ALLEGRO_AUDIO_STREAM(3).  The stream will be set to play by
17       default.  It will feed audio data from a buffer, which is split into  a
18       number of fragments.
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20       Parameters:
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22       · fragment_count  -  How  many  fragments  to use for the audio stream.
23         Usually only two fragments are required - splitting the audio  buffer
24         in  two halves.  But it means that the only time when new data can be
25         supplied is whenever one half has finished playing.  When using  many
26         fragments,  you  usually  will  use  fewer  samples for one, so there
27         always will be (small) fragments available  to  be  filled  with  new
28         data.
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30       · frag_samples - The size of a fragment in samples.  See note below.
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32       · freq - The frequency, in Hertz.
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34       · depth - Must be one of the values listed for ALLEGRO_AUDIO_DEPTH(3).
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36       · chan_conf  -  Must  be  one  of  the  values listed for ALLEGRO_CHAN‐
37         NEL_CONF(3).
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39       The choice of fragment_count, frag_samples and freq directly influences
40       the audio delay.  The delay in seconds can be expressed as:
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42              delay = fragment_count * frag_samples / freq
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44       This  is  only the delay due to Allegro's streaming, there may be addi‐
45       tional delay caused by sound drivers and/or hardware.
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47              Note: If you know the fragment size in bytes, you  can  get  the
48              size in samples like this:
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50                     sample_size = al_get_channel_count(chan_conf) * al_get_audio_depth_size(depth);
51                     samples = bytes_per_fragment / sample_size;
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53              The size of the complete buffer is:
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55                     buffer_size = bytes_per_fragment * fragment_count
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57              Note: Unlike many Allegro objects, audio streams are not implic‐
58              itly destroyed when Allegro is shut down.  You must destroy them
59              manually with al_destroy_audio_stream(3) before the audio system
60              is shut down.
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64Allegro reference manual                             al_create_audio_stream(3)
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