Narecord - Townshend Computer Tools DAT-Link User Manual

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NAME
narecord – record from a DAT machine to an audio file
SYNOPSIS
narecord [ –a ] [ –c control_file ] [ –C ] [ –e encoding ] [ –f format ] [ –i input_source ] [ –n samples ]
[ –o channels ] [ –p precision ] [ –q ] [ –s file_sampling_rate ] [ –t seconds ] [ –u host:unit ] [ file ]
D ESCRIPTION
narecord transfers digital audio input to file via a DAT-Link interface using the NetAudio server. See
netaudiod(8) for details on the NetAudio server. narecord can be used to record a live input onto
d isk, or to transfer audio data from tape to file. To record, an analog-to-digital converter or digital audio
tape (DAT) machine must be connected to one of the DAT-Link's digital input ports.
A DAT machine can be used either to transfer audio data from tape to file, or to record a live input to
file. To record live analog inputs, the DAT machine must be put in paused-record mode with its inpu
s ource set to analog. This allows the machine to convert it's analog inputs to a digital output stream
which is passed through the DAT-Link interface to the host computer. On some machines a blank tap
m ust be inserted before paused-record is permitted. To transfer from a DAT tape to file, the DAT
machine just needs to be put into normal play mode before running narecord. The –a option can als
b e used to set the appropriate DAT machine modes via remote control if the machine is so equipped
(see rctrain(1)).
I f no file is given on the command line, output is sent to the standard output. Unless the –t or –n
option is used, recording will continue until narecord is interrupted by the user.
OPTIONS
–a narecord will use the DAT-Link's infrared remote control to start the DAT machine playing
before beginning transfer of data to file. After the file has been transferred, the DAT machin
w ill be stopped. A few seconds of silence will be recorded into the beginning of file, unless
the –q option is also given. Note that the
name of the remote control description for the DAT machine. Available choices for
c an be listed using the rc(1) command. If a description has not already been installed for the
DAT machine in use, it can be created using rctrain(1).
– c This option allows the user to capture the channel status and user bits of the digital audio out-
puts in the given file. This file can be edited using any text editor. Each line of the file is a
b inary representation of single byte of data, least significant bit first, and must contain 8 ones
or zeroes with no other characters. The first 24 lines are the channel status bytes for the lef
c hannel outputs. The next 24 are the right channel status bytes. The final 48 bytes specify the
user bytes, which are spread across both the left and right channels. For details of the interpre
t ation of these bits refer to the appropriate digital audio standards.
–C In this mode, the channel status and user bits are stored with the audio data in file. Each sam
ple is stored as a 32 bit number with some bits representing the audio data while others are the
control and auxiliary information. Starting from the most-significant bit of the first byte in th
fi le, the data is stored as: Parity (1bit), Channel Status (1bit), User (1bit), Validity (1bit), Data
(20 bits), Aux Data (4bits), zeroes (4bits). If recording in stereo, the left and right sample
i ncluding all control information, are interleaved.
–e encoding
Specify the encoding of the data to be transferred. All encodings use most-significant-byte first
ordering. Note that this controls the encoding used by the DAT-Link -- the data may undergo
a dditional conversions depending on the file format chosen. Valid choices for the encoding
are:
L inear Linearly encoded data with a fixed number of bits per sample. This is the default
encoding. The number of bits per sample can be set using the -p option.
I EEE IEEE floating-point encoding with 4 bytes/sample.
NetAudio Reference
environment variable must be set to the
DL_RC
Last change: 1995/02/08

NARECORD(1)

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