NA_PLAY(1)						    BSD General Commands Manual 						NA_PLAY(1)

NAME

     na_record -- play waveform files on audio device

SYNOPSIS

     na_play [-h] [-itype type] [-n channels] [-f sample rate] [-ibo byteorder] [-iswap] [-istype type] [-c channel] [-start time] [-end time]
	     [-from sample] [-to sample] [-p protocol] [-command command] [-basic] [-quality high | low] [-server host] [-scale scale] [-v]
	     [-wait] input files ...

DESCRIPTION

     na_play plays digital audio data to the system's audio input device from the specified file(s).  It supports a variety of file formats and
     native audio devices.

     The following option flags are recognized:

	   -h	 Prints a short summary of usage to standard output.
	   -itype type
		 Input file type.  Usually, the input type can be determined from the file's headers, so this option is not required except for
		 raw (unheadered) data.  Supported types are currently: nist, est, esps, snd, riff, aiff, audlab, raw, ascii.
	   -n channels
		 Number of channels, in an unheadered input file.  Again, this can usually be determined from the headers.  Default is 1.
	   -f sampling rate
		 Sampling rate, for an unheadered input file.  Default is 16000.
	   -ibo byte order
		 Byte order, for an unheadered input file.  Default is system byte order.  Recognized values are: MSB, LSB, native, nonnative.
	   -iswap
		 Swap bytes in an unheadered input file.
	   -istype type
		 Sample type for an unheadered input file.  Recognized values are: short, mulaw, byte, ascii.
	   -c channel
		 Select a single channel (starting at 0) for playback.	This option plays only the specified channel and discards all others.
	   -start time
		 Select a subsection of the file, starting at this time (specified in seconds).
	   -end time
		 Select a subsection of the file, ending at this time (specified in seconds).
	   -from sample
		 Select a subsection of the file, starting at this offset (specified in number of samples).
	   -to sample
		 Select a subsection of the file, ending at this offset (specified in number of samples).
	   -p protocol
		 Use the specified audio device protocol.  The list of supported types varies between platforms, and can be obtained using the -h
		 flag.
	   -command command
		 If the "audio_command" protocol is specified, this argument must be given to select the command used to play the waveform.  A
		 temporary file is created and passed in the environment variable FILE.  The sample rate is passed in the environment varialbe SR.
	   -basic
		 Treat unheadered input files as 8kHz mu-law data (i.e. audio/basic MIME type)
	   -quality high | low
		 Select the quality of output. "high" will ensure that proper resampling is used.  "low" means to play as fast as possible with a
		 minimum of processor time.
	   -server host
		 Specifies the host to play sound on, when using a network-aware audio protocol (such as NAS)
	   -scale scale
		 Change the gain (volume) of the signal.  The argument is a number relative to 1.0, which is the default.
	   -v	 Be verbose (i.e. print file names when playing)
	   -wait
		 Pause for a keystroke between each file.

ENVIRONMENT

	   NA_PLAY_PROTOCOL
		 Audio protocol to use (as in the -p flag)
	   NA_PLAY_COMMAND
		 Command used to play audio when using the audio_command protocol.
	   NA_PLAY_HOST
		 Host to play audio on when using a network audio protocol.
	   NA_PLAY_QUALITY
		 Playback quality (low or high)

EXAMPLES

     To play the section of foo.wav from 1.5 to 3.2 seconds:
	   $ na_play -start 1.5 -end 3.2 foo.wav
     To play samples 3600 to 42000 of channel 1 of bar.wav:
	   $ na_play -from 3600 -to 4200 -c 1 foo.wav

BUGS

     The usage information isn't entirely correct. The audio_command protocol generates temporary files insecurely.

SEE ALSO

     na_record(1)

Edinburgh Speech Tools						   April 4, 2001					    Edinburgh Speech Tools