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play_audio_stream(3)            Allegro manual            play_audio_stream(3)


NAME

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


SYNOPSIS

       #include <allegro.h>

       AUDIOSTREAM *play_audio_stream(int len, int bits, int stereo, int freq,
       int vol, int pan);


DESCRIPTION

       This function creates a new audio stream and starts playing it. The
       length is the size of each transfer buffer in sample frames (not
       bytes), where a sample frame is a single sample value for mono data or
       a pair of interleaved sample values (left first) for stereo data. The
       length should normally be (but doesn't have to be) a power of 2
       somewhere around 1k in size. Larger buffers are more efficient and
       require fewer updates, but result in more latency between you providing
       the data and it actually being played.

       The `bits' parameter must be 8 or 16. `freq' is the sample rate of the
       data in Hertz. The `vol' and `pan' values use the same 0-255 ranges as
       the regular sample playing functions. The `stereo' parameter should be
       set to 1 for stereo streams, or 0 otherwise.

       If you want to adjust the pitch, volume, or panning of a stream once it
       is playing, you can use the regular voice_*() functions with
       stream->voice as a parameter. The format of the sample data is
       described in the SAMPLE entry of the "Structures and types defined by
       Allegro" chapter. The formula to get the size of the buffers in bytes
       could be:

          bytes = length * (bits / 8) * (stereo ? 2 : 1)
       Example:

          /* Create a 22KHz 8bit mono audio stream. */
          stream = play_audio_stream(1024, 8, FALSE, 22050, 255, 128);
          if (!stream)
             abort_on_error("Error creating audio stream!\n");


RETURN VALUE

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


SEE ALSO

       install_sound(3), get_audio_stream_buffer(3), stop_audio_stream(3),
       AUDIOSTREAM(3), exstream(3)

Allegro                          version 4.4.2            play_audio_stream(3)

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