tuneR (version 0.4-2)

lifter: Liftering of cepstra

Description

Apply liftering to a matrix of cepstra.

Usage

lifter(x, lift = 0.6, inv = FALSE, htk=FALSE)

Arguments

x

Matrix of cepstra, one sample/time frame per column.

lift

Liftering exponent/length.

inv

Invert the liftering (undo a previous liftering).

htk

Switch liftering type.

Value

• Matrix of the liftered cepstra.

concept

liftering

Details

If htk=FALSE, then perform $x i^lift$, $i = 1, ldots, nrow(x)$ liftering. If htk=TRUE, then perform HTK-style sin-curve liftering with length lift.

References

Daniel P. W. Ellis: http://www.ee.columbia.edu/~dpwe/resources/matlab/rastamat/

Examples

testsound <- normalize(sine(400) + sine(1000) + square(250), "16")
  m <- melfcc(testsound, frames_in_rows=FALSE)
  unlm <- lifter(m, inv=TRUE)