Rwave (version 2.4-8)

icm: Ridge Estimation by ICM Method

Description

Estimate a (single) ridge from a time-frequency representation, using the ICM minimization method.

Usage

icm(modulus, guess, tfspec=numeric(dim(modulus)[2]), subrate=1,
mu=1, lambda=2 * mu, iteration=100)

Arguments

modulus

Time-Frequency representation (real valued).

guess

Initial guess for the algorithm.

tfspec

Estimate for the contribution of the noise to modulus.

subrate

Subsampling rate for ridge estimation.

mu

Coefficient of the ridge's second derivative in cost function.

lambda

Coefficient of the ridge's derivative in cost function.

iteration

Maximal number of moves.

Value

Returns the estimated ridge and the cost function.

ridge

1D array (of same length as the signal) containing the ridge.

cost

1D array containing the cost function.

Details

To accelerate convergence, it is useful to preprocess modulus before running annealing method. Such a preprocessing (smoothing and subsampling of modulus) is implemented in icm. The parameter subrate specifies the subsampling rate.

References

See discussions in the text of ``Practical Time-Frequency Analysis''.

See Also

corona, coronoid, and snake, snakoid.