AUDEMO(1)AUDEMO(1)NAMEaudemo - Network Audio System record and play demo
SYNOPSISaudemo [-audio servername] [-toolkitoption ...] [directory]
DESCRIPTIONaudemo provides an X-based window-oriented user interface to the Net‐
work Audio System service. It allows the user to play pre-recorded
sound files, record new sound files and to manipulate Network Audio
System buckets.
AUDEMO AND THE ATHENA WIDGET SETaudemo uses the X Toolkit Intrinsics and the Athena Widget Set. For
more information, see the Athena Widget Set documentation.
SCREEN LAYOUTaudemo starts out with a single window divided into several areas:
o A collection of command buttons.
o A left and right level meter.
o A volume indicator and control slider.
o An information window.
o An editable field containing the directory to be searched for sound
files.
o An editable field containing a list of sound files to search for.
o A window containing the list of sound files that may be selected
for playing or loading into buckets.
PLAYING A SOUND FILE
To play a sound file you must first select it from the list of files in
the file window. You can control which files are listed in this window
by editing the Directory and/or Template fields and clicking on the
Rescan button. To select a file, single-click on the filename. This
will highlight the filename and display information about the file in
the information window. The information displayed includes:
Filename
The full pathname of the file.
File Format
The file format of the audio file.
Data Format
The encoding format of the audio data.
Tracks
The number of tracks of audio data.
Frequency
The frequency at which the audio data was sampled.
Duration
The duration of the audio data in seconds.
Text
Any text information stored in the file.
Once the file has been selected, you can start it playing by clicking
on the Play command button. A shortcut for playing a file is to dou‐
ble-click on the file name. This will select the file and start it
playing. When a file is playing, the Play command button is high‐
lighted. To stop the playing of a file, click on the highlighted Play
button. To enable the left and right level meters, click on the Meter
button before starting to play the file. To disable the left and right
level meters, click again on the highlighted Meter button. To adjust
the volume level, use the volume slider.
RECORDING TO A FILEaudemo can record sound files in any supported file and data format.
To record a sound file you must first bring up the record window by
clicking on the Record command button. This will bring up a window
containing the following fields and controls:
Filename
The name of the file you wish to create. Unless a path is speci‐
fied here, the file will be created in the current directory.
File Format
A menu of file formats.
Data Format
A menu of data formats. Note that each file format does not neces‐
sarily support all of the data formats listed.
Max Duration
See RECORDING TO A BUCKET.
Read Only
See RECORDING TO A BUCKET.
Frequency
The sampling rate (in hertz) for the recording. Higher sampling
rates yield better quality sound but take up more disk and memory
space. Common sampling rates are 8000 (good for voice annota‐
tions), 11000, 22000, and 44000.
Mic(rophone)
This button tells the audio server if you've got a microphone
attached to the audio input jack. Clicking this button will high‐
light it and cause the audio server to boost the input gain to a
level suitable for recording with a microphone.
Comment
Text (such as a description) you wish to put into the audio file.
Gain
This slider is used to adjust the recording gain level.
Record
This button starts or stops the recording.
Monitor
This button enables or disables monitoring.
New Bucket
See RECORDING TO A BUCKET.
Dismiss
This button stops recording and monitoring and closes the record
window.
Once you have selected the filename, file and data formats, frequency,
mic level, comment and gain, you are ready to record. To listen in on
the audio that will be recorded you can click on the Monitor button.
This will direct all the audio received from the audio input jack to be
played on the speaker. When you're ready to record, click on the
Record button. All the audio received from the audio input jack will
now be recorded into the file. The recording will continue until you
click on the Record button again or click on the Dismiss button. NOTE:
Audio data can accumulate very rapidly, especially at high sampling
rates, resulting in large files.
BUCKETS
The Network Audio System service provides the capability to create
server resident sound objects called buckets. audemo allows the user
to create buckets, record into them, play from them, load them with
data from a file and dump their contents into a file. Note that buck‐
ets created by audemo are destroyed when audemo is terminated. These
options are available when you bring up the buckets window by clicking
on the Buckets button in the main window. The buckets windows is
divided into two areas:
o A collection of command buttons.
o A table of buckets currently accessible. This table contains the
following columns:
Description
The text description.
Duration
The duration of the audio data in seconds.
Tracks
The number of tracks of audio data.
Frequency
The frequency at which the audio data was sampled.
Format
A code letter indicating the encoding format of the audio data.
A key to the format code letters can be displayed by clicking
on the Format Key button.
Access
A combination of code letters indicating the access mode of the
bucket. A key to the access code letters can be displayed by
clicking on the Access Key button.
CREATING A BUCKET FROM A FILE
To create a bucket from from an audio data file, select the filename
from the list of files in the file window then click the Load button in
the buckets window. The first line of the buckets table should now
contain the information about the newly created bucket.
PLAYING FROM A BUCKET
To play a bucket, select the bucket you wish to play by clicking on
it's information in the buckets table. The entry you click on should
be highlighted. Then click on the Play button in the buckets window.
A shortcut for playing from a bucket is to double-click on the bucket
information. This will select the bucket and start playing from it.
To stop the playing of a bucket, click on the highlighted Play button
in the buckets window. The level meters and volume level can be con‐
trolled in the same way as when playing from a file.
RECORDING TO A BUCKET
To record into a new bucket, click on the Record button in the buckets
window. This will bring up the record window. This record window is
the same as the one used for recording to files. Instead of specifying
a filename, in the Max Duration field, enter the maximum duration (in
seconds) of data that the bucket is to hold. Clicking on the Read Only
button will prevent other applications from writing into or destroying
the bucket. The frequency, mic level, format and comment are used in
the same way as when recording to files. Once all of the fields are
set appropriately, click the New Buckett button. This will create a
new bucket according to the specifications given. The first line of
the buckets table should now contain the information about the newly
created bucket. To begin recording into the bucket, select the bucket
by clicking on it's information in the buckets table. Then click the
Record button in the record window. All the audio received from the
audio input jack will now be recorded into the bucket. The recording
will continue until you click on the Record button again, click on the
Dismiss or the bucket is filled. The Gain slider and the Monitor but‐
ton operate the same as when recording to a file.
SAVING A BUCKET TO A FILE
To save a bucket to a file, first select the bucket by clicking on its
information in the buckets table. Then click on the Save button in the
buckets window. A dialog box will pop up prompting you for the name of
the file in which to save the bucket data, and the file format. The
data format used will be that of the bucket. Note that each file for‐
mat may only support selected data formats. If no path is given in the
filename, the file will be created in the current directory. Clicking
on Ok or pressing the RETURN key will cause the file to be created and
the data from the bucket to be written to the file.
DELETING A BUCKET
To delete a bucket, first select the bucket by clicking on it's infor‐
mation in the buckets table. Then click on the Delete button in the
buckets window. If the audemo has the appropriate access permissions
for the bucket, the bucket will be deleted and it's information will be
removed from the bucket table.
EXITING AUDEMO
Clicking on the Quit button will cause audemo to exit, stopping any
playing or recording operations and destroying any buckets that were
created.
COMMAND LINE OPTIONS-audio servername
This option specifies the Network Audio System server to which
audemo should connect.
directory
The directory name that audemo will use to build the list of
selectable file names. When directory is not specified on the
command line, the current working directory is used.
EXAMPLES
In the following example, in a TCP/IP network, mcxterm is the name of
the desktop machine running the audio server. The default port is 8000
and sound files are located in ~/snd:
audemo-audio tcp/mcxterm:8000 ~/snd
In the following example, the shortened form of the audio server name
is used and sound files from the current working directory will be
used:
audemo-audio mcxterm:0
ENVIRONMENT
In addition to the standard toolkit environment variables, the follow‐
ing environment variables are used by audemo:
AUDIOSERVER
This variable specifies the default audio server to contact if
-audio is not specified on the command line. If this variable
is not set and the -audio is not specified on the command line,
audemo will attempt to connect to the audio server running on
the X Window System display.
BUGS
Warning: audemo is the xterm of the Network Audio System. It was writ‐
ten to test features as the Network Audio System was being developed.
It was also the author's first Xt program. Consequently, it's pretty
ugly and should be completely re-written from scratch.
SEE ALSOnas(1), X(1)COPYRIGHT
Copyright 1993, 1994 Network Computing Devices, Inc.
AUTHOR
Greg Renda, Network Computing Devices, Inc.
1.9.3 AUDEMO(1)
