1play_audio_stream(3)            Allegro manual            play_audio_stream(3)
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NAME

6       play_audio_stream  -  Creates a new audio stream and starts playing it.
7       Allegro game programming library.
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SYNOPSIS

10       #include <allegro.h>
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13       AUDIOSTREAM *play_audio_stream(int len, int bits, int stereo, int freq,
14       int vol, int pan);
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DESCRIPTION

17       This  function  creates  a  new audio stream and starts playing it. The
18       length is the size of  each  transfer  buffer  in  sample  frames  (not
19       bytes),  where a sample frame is a single sample value for mono data or
20       a pair of interleaved sample values (left first) for stereo  data.  The
21       length  should  normally be (but doesn't have to be) a power of 2 some‐
22       where around 1k in size. Larger buffers are more efficient and  require
23       fewer  updates,  but  result  in more latency between you providing the
24       data and it actually being played.
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26       The `bits' parameter must be 8 or 16. `freq' is the sample rate of  the
27       data  in Hertz. The `vol' and `pan' values use the same 0-255 ranges as
28       the regular sample playing functions. The `stereo' parameter should  be
29       set to 1 for stereo streams, or 0 otherwise.
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31       If you want to adjust the pitch, volume, or panning of a stream once it
32       is  playing,  you  can  use  the  regular  voice_*()   functions   with
33       stream->voice  as  a  parameter.  The  format  of  the  sample  data is
34       described in the SAMPLE entry of the "Structures and types  defined  by
35       Allegro"  chapter.  The formula to get the size of the buffers in bytes
36       could be:
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38          bytes = length * (bits / 8) * (stereo ? 2 : 1)
39       Example:
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41          /* Create a 22KHz 8bit mono audio stream. */
42          stream = play_audio_stream(1024, 8, FALSE, 22050, 255, 128);
43          if (!stream)
44             abort_on_error("Error creating audio stream!\n");
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RETURN VALUE

47       This function returns a pointer to the audio stream or NULL if it could
48       not be created.
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SEE ALSO

52       install_sound(3),   get_audio_stream_buffer(3),   stop_audio_stream(3),
53       AUDIOSTREAM(3), exstream(3)
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57Allegro                          version 4.2.2            play_audio_stream(3)
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