Draw the amplitude envelope of a time wave
This function lets the user modifying the amplitude envelope of a time wave by drawing it with the graphics device
drawenv(wave, f, channel = 1, n = 20, plot = FALSE, listen = FALSE, output = "matrix")
wave |
an R object. |
f |
sampling frequency of |
channel |
channel of the R object, by default left channel (1). |
n |
the maximum number of points to draw the new envelope. Valid values start at 1. |
plot |
if |
listen |
if |
output |
character string, the class of the object to return, either
|
The function first plots an oscillogram view of wave.
The user has then to choose points on the positive side of the y-axis (amplitude).
The junction of these points will draw a new amplitude envelope.
The order of points along the x-axis (time) is not important
but points cannot be cancelled. When this process is finished
the new time wave is returned in the console or as an oscillogram
in a second graphics device if plot is TRUE.
The function uses locator.
If plot is FALSE, a new wave is returned. The class
of the returned object is set with the argument output.
Jerome Sueur sueur@mnhn.fr
## Not run: a<-synth(d=1,f=22050,cf=1000) # drawenv(a,f=22050,plot=TRUE) # choose points on the oscillogram view to draw a new enveloppe # stop (ESC on Windows; right mouse button on Linux) # check the result on the second graphics device opened thanks to plot=TRUE ## End(Not run)
Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.