RMENC(1)
NAME
rmenc - encode .au or .wav file or live audio input into a
RealAudio file
SYNOPSIS
rmenc -I infile.wav -O outfile.rm -A codec
DESCRIPTION
rmenc encodes audio files into the RealMedia file format
for real-time delivery over the Internet. On some UNIX
systems, rmenc can also capture audio input from a sound
card, and deliver the encoded stream either to a file on
disk or to a RealServer on the Internet.
RealAudio content may be created from previously recorded
digital audio files. Prerecorded files may be in .au (mu-
law, 8-bit or 16-bit signed) and .wav (RIFF/WAV)( 8-bit
unsigned or 16-bit signed).
If you have files in formats other than those the encoder
supports, you can use the Sox tool to convert your files
into .pcm, .wav, or .au file formats. You can find Sox at
the following location:
http://www.spies.com/Sox/
The RealEncoder compresses the audio data stream and pre-
pares it for use with the RealServer. This compression is
"lossy", which means that some of the information con-
tained in the original audio data stream is removed. To
ensure that you will get optimal audio quality after
encoding, you must start with a high fidelity recording
which utilizes the full dynamic range and has a high sig-
nal to noise ratio. In addition, you will have better
results if you use simple audio signals rather than com-
plex signals.
Prior to encoding, prerecorded audio should be prepro-
cessed using one of the various sound editing utilities
available to maximize the audio quality of the encoded
content.
For an in-depth explanation about pre-processing audio,
see "Getting the Best Sound out of RealAudio" on the Real-
Networks Web site at:
http://www.real.com/help/content/audiohints.html
OPTIONS
[ -I input filename ]
[ -O outfile filename ]
[ -T title string ]
[ -U author string ]
[ -C copyright string ]
[ -A audio codec index ]
[ -R [ 0 | 1 ] ]
[ -P [ 0 | 1 ] ]
[ -S server[:port]/resource ]
[ -W encoder password ]
[ -T encoding file duration ]
[ -Z config file ]
[ -L ]
[ -h ]
The following options are supported by the RealEncoder:
-I infile specifies an input file name. There is no
default file name.
-O outfile
specifies an output file name. The default file
name is the input file name with a ".rm" suffix.
-T "title"
specifies a title string for the output file.
This is optional.
-U "author"
specifies an author string for the output file.
This is optional.
-C "copyright"
specifies a copyright string for the output
file. This is optional.
-A codec index
specifies which codec to use to encode the
input. Running the encoder with the -H argument
will display a list of available codecs.
-a audio capture input device index
specify that input is to be taken from the sound
card instead of from a pre-recorded audio file.
The index to specify is displayed in the output
from the -H command. Note that this option is
not available on all systems; refer to the Real-
Networks web site for more information
(www.real.com).
-x audio input port
Many sound cards support line-in or microphone
input, and cd can be used if a CD-ROM is con-
nected to the sound card. Note that the encoder
does not read directly from the CD; it relies on
an external application (such as workman) to
start playback of the CD.
-R [ 0 | 1 ]
enable or disable Selective Record. This is
optional.
-P [ 0 | 1 ]
enable or disable PerfectPlay. This is optional.
-H prints out the usage message and exits.
-T dd:hh:mm:ss
specify to halt the encoding after the requested
time interval has elapsed. This option is used
for live input sources only.
LIVE BROADCAST SUPPORT
Some versions of the encoder support the ability to stream
output directly to a RealAudio server, making the content
available for listening immediately. This option is cur-
rently only supported for input directly from the sound
card. The following options on the command line instruct
the encoder to send its output to a RealAudio server:
-S hostname[:port]/resource.rm
specify the name of the host that the server is
running on, the port number, and the name of the
file to stream.
-W password
specify the password needed to connect to the
server or LTA.
MULTIPLE LIVE BROADCASTS
Versions of the encoder which support live broadcast also
have the ability to create multiple output streams simul-
taneously; this is useful for creating two or more streams
of varying bitrates (or other audio characteristics) from
a single live source. This is enabled by a config file
which contains the following sections:
[ global ]
device = device number of audio input plugin.
input = input number corresponding to input on audio card.
timeout = DD:HH:MM:SS
The global settings section controls where the input sig-
nal is coming from; the device number and input number are
the same as the ones used with the -a and -x options when
running a single live encoding session.
For each output stream, a section with the following
parameters needs to be created:
[ session name ]
where session name is a piece of descriptive text to be
associated with the encoding process.
title = title text (optional)
author = author text (optional)
copyright = title text (optional)
codec = codec name (required)
flavor = flavor number (required)
destination = a comma separated list of server and/or file
password = password used to connect to server; used if
server is specified as one of the destination values
server = server name
port = port number
filename = output file name (required if saving to file)
url = url name (required if streaming to server)
ENVIRONMENT VARIABLES
LD_LIBRARY_PATH is used to locate shared libraries (codecs
and input plugins); all the or they must be installed in
default system directories (typically /usr/lib and /lib).
RV_PLUGIN_DIR is used to tell the encoder where to find
input plugins.
AUDIODEV is used to specify a different audio device.
EXAMPLES
To encode a RIFF file into stereo 28.8 RealAudio, use the
following command:
rmenc -T "My Title" -U "My Name" -A 3 -O myfile.rm -I
myfile.wav
To encode from the audio input device shown in the help
screen printed above, use the following command (to read
from the line in jack):
rmenc -a 2 -x 1 -A 4 -O file.rm
To encode from the audio input device to your RealServer:
rmenc -a 2 -x 1 -A 4 -S server:7070/live.rm -W password
NOTICES
Copyright (c) 1996, 1997, Real Networks, Inc. All rights
reserved.