seewave (version 1.5.5)

revw: Time reverse of a time wave

Description

Reverse the wave along the time axis.

Usage

revw(wave, f, env = TRUE, ifreq = TRUE, plot = FALSE, Sample = FALSE, ...)

Arguments

wave

a vector, a matrix (first column), an object of class ts, Sample (left channel), or Wave (left channel).

f

sampling frequency of wave (in Hz). Does not need to be specified if wave is an object of class ts, Sample, or Wave<

env

logical, if TRUE the amplitude envelope is reversed.

ifreq

logical, if TRUE the instantaneous frequency is reversed.

plot

logical, if TRUE returns an oscillographic plot of the reversed wave (by default FALSE).

Sample

logical, if TRUE and plot is FALSE returns an object of class Sample

...

other oscillo graphical parameters.

Value

• If plot is FALSE, a new wave is returned as a one-column matrix or as a Sample object if Sample is TRUE.

Details

If plot is TRUE returns an oscillogram of the reversed wave. The amplitude and the instantaneous frequency can be independently reversed thanks to the arguments env and ifreq. See the examples.

References

Beeman, K. 1998. Digital signal analysis, editing and synthesis in Hopp, S. L., Owren, M. J. and Evans, C. S. (Eds) 1998. Animal acoustic communication, pp. 59-103. Springer, Berlin, Heidelberg.

See Also

oscillo, addsilw, deletew, fadew, pastew, mutew

Examples

data(tico)
# simple reverse
revw(tico,f=22050,plot=TRUE)
# envelope reverse only
revw(tico,f=22050,ifreq=FALSE, plot=TRUE)
# instantaneous frequency reverse only
revw(tico,f=22050,env=FALSE, plot=TRUE)