SYNOPSISna_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 ...
DESCRIPTIONna_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:
- 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.
- 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.
- 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.
- Be verbose (i.e. print file names when playing)
- Pause for a keystroke between each file.
- Audio protocol to use (as in the -p flag)
- Command used to play audio when using the audio_command protocol.
- Host to play audio on when using a network audio protocol.
- Playback quality (low or high)
EXAMPLESTo 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"