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NAME
     audio_misc,    audio_bytes_to_secs,     audio_secs_to_bytes,
     audio_str_to_secs,     audio_secs_to_str,     audio_cmp_hdr,
     audio_enc_to_str - miscellaneous audio functions

SYNOPSIS
     #include <multimedia/libaudio.h>

     double audio_bytes_to_secs(Audio_hdr *hp,
     unsigned cnt);

     unsigned audio_secs_to_bytes(Audio_hdr *hp,
     double secs);

     double audio_str_to_secs(char *str);

     char *audio_secs_to_str(double secs,
     char *str,
     int precision);

     int audio_cmp_hdr(Audio_hdr *hp1,
     Audio_hdr *hp2);

     int audio_enc_to_str(Audio_hdr *hp,
     char *str);

DESCRIPTION
     These functions perform some simple, useful transformations.

     audio_bytes_to_secs()  converts  a   byte   count   into   a
     floating-point  time value that is appropriate to the encod-
     ing described by the given audio  header.   The  time  value
     returned  indicates the number of seconds of data that would
     correspond to cnt bytes.  Note that a byte count is not  the
     same  as  an  offset in an audio file, since the size of the
     audio file header is not taken into account.

     audio_secs_to_bytes() converts a floating-point  time  value
     into  a  byte  count  that  is  appropriate  to the encoding
     described by the given audio  header.   The  byte  count  is
     rounded  down  to  a  sample frame boundary; this guarantees
     that the returned count will not refer to an offset  in  the
     middle of a multi-byte sample frame.

     audio_str_to_secs()  converts  an  ASCII   string   into   a
     floating-point  time  value,  in seconds.  The string should
     take the form:
          [hh:][mm:][ss][.dd]

     For example, the following strings all  convert  to  to  the
     floating-point value 90.5:

          90.5
          1:30.5
          0:01:30.500

     If the given string  contains  a  syntax  error,  the  value
     HUGE_VAL is returned.

     audio_secs_to_str() converts  a  floating-point  time  value
     into  an ASCII string of the form hh:mm:ss.dd.  As a special
     case, the value HUGE_VAL is converted to the string The pre-
     cision  argument  specifies  the maximum number of digits to
     appear after the decimal point.  A precision of  -1  guaran-
     tees  the maximum precision necessary to represent the given
     time.  The str argument is a pointer to a buffer of at least
     AUDIO_MAX_TIMEVAL  bytes.   For  convenience, the address of
     the converted string is returned as the function value.

     audio_cmp_hdr() compares the encoding information fields  of
     the  two  specified  audio  headers, returning 0 if they are
     identical.  If the encoding type and precision match but the
     sample rates are different, 1 is returned.  Otherwise, -1 is
     returned.

     audio_enc_to_str() converts the encoding information in  the
     given audio header to a printable ASCII string, e.g.:
          mono 8-bit u-law @ 8kHz
          stereo 16-bit linear PCM @ 44.1kHz

     The str argument is a  pointer  to  a  buffer  of  at  least
     AUDIO_MAX_ENCODE_INFO  bytes.  On successful completion, the
     value AUDIO_SUCCESS is returned.  If any fields of the audio
     header  cannot be interpreted, the value AUDIO_ERR_BADHDR is
     returned, with an appropriate string stored in the buffer.

SEE ALSO
     audio_hdr(3)

WARNINGS
     The manual pages, header files, and object  library  associ-
     ated  with /usr/demo/SOUND/libaudio.a are furnished on an as
     is basis as a preliminary interface to several useful  audio
     data-processing  capabilities.   A  future  release  of  the
     operating system may redefine the  syntax  or  semantics  of
     some of the functions described herein.

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