NAME
jack.scope - JACK Oscilloscope
SYNOPSIS
jack.scope [options]
OPTIONS
-b Set the frame size of the data displayed by the scope
(default=512).
-d Set the delay interval in milli-seconds between scope updates
(default=100.0).
-e Set the embedding delay time in samples (default=6). The
delayed sample is on the x-axis.
-f Request that a still image file of each frame be stored to the
indicated directory.
-i Set the embedding interpolation increment (default=1.0).
Smaller values provide more continuous trace paths.
-m Set the scope operating mode (default=signal). The operating
modes are: signal and embed.
-n Set the number of channels, and therefore the number of JACK
input ports (default=1). Multiple channels are superimposed,
each channel is drawn in a distinct color. There is a compile
time channel limit.
-p Set the port number to listen for OSC packets on
(default=57140).
-s Set the drawing style (default=dot). The drawing styles are:
dot, fill and line.
-w Set the scope size in pixels (default=512). The scope window is
square.
DESCRIPTION
jack.scope is an oscilloscope for JACK under X11. jack.scope draws
either a time domain signal trace or a self correlation trace.
Multiple input channels are superimposed, each channel is drawn in a
different color. jack.scope accepts OSC packets for interactive
control of drawing parameters.
The operating mode of jack.scope is set using -m. In signal mode
jack.scope draws a time domain signal trace, in embed mode jack.scope
draws a self correlation trace.
The size of the jack.scope window is set using -w, the scope window is
square. The window is of fixed size and has centered gravity. The
time interval that is displayed is determined by the frame size, set
using -b. The image refresh rate is determined by the delay interval,
set using -d. Note that the interval is truncated to the nearest frame
boundary and that the time taken to compose the image and blit to the
screen is indeterminate.
The number of JACK input ports that jack.scope creates and monitors is
set using -n. Multiple channels are drawn in superimposition, each
channel is drawn in a distinct color.
In signal mode the trace is drawn in a style determined by -s. In dot
mode only the sample pixel in each column is drawn. In fill mode all
pixels between the sample pixel and the zero pixel of each column are
drawn. In line mode all pixels between the adjacent sample pixels of
each column are drawn.
In embed mode the trace is a self correlation signal with a sample
delay set using -e. The delayed sample is on the x-axis. The
interpolation increment is set using -i, increment values less than one
result in increasingly continuous trace paths.
jack.scope can store the animation as a sequence of uncompressed ppm(5)
image files. To request this use the -f option with the directory
files should be written to as the argument.
The OSC messages understood by jack.scope are given in the table below.
Each command requires one argument of the indicated type. The last
column gives the option that sets the same parameter.
/jsc_md drawing-mode <string> -m
/jsc_st style <string> -s
/jsc_fs frame-size <integer> -b
/jsc_ri refresh-interval <float> -d
/jsc_ef embedding <integer> -e
/jsc_ei increment <float> -i
jack.scope implements no connection logic, use jack.plumbing(1)
instead.
REFERENCES
Monro, G. and Pressing, J. ‘‘Sound Visualization Using Embedding: The
Art and Science of Auditory Autocorrelation’’ CMJ, 22/2, 1998.
SEE ALSO
jackd(1), X(7x), OSC(7) <http://cnmat.berkeley.edu/OSC/>
AUTHORS
Rohan Drape.