SpectrumTier

Holds the frequency peaks picked out of a long-term average spectrum.

Arguments

.xptr

Not for direct use. External pointer to the underlying C++ object; set internally by ltas$to_spectrum_tier_peaks().

Value

A SpectrumTier object with methods for reading its frequency/power points.

Details

A SpectrumTier is the result of peak-picking an Ltas: each point is one local maximum, recorded as a frequency and its power in dB. Use it to pull out harmonic or formant-like peaks from a spectral average without scanning the raw values by hand. It's read-only: build one with ltas$to_spectrum_tier_peaks(), then inspect or export it.

Usage

peaks <- ltas$to_spectrum_tier_peaks()

Query methods

• get_lowest_frequency(), get_highest_frequency() - the frequency range the peaks were picked from, in Hz

• get_number_of_points() - number of peaks found

• get_frequency_from_index(index) - frequency of one peak

• get_value_at_index(index) - power of one peak, in dB

Export

• as_data_frame() - all peaks as a data frame, with frequency and power_db columns

• as_matrix() - the same data as a plain matrix

• save(path) - write to a Praat text file

See also

Ltas

Examples

sound <- Sound$create_tone(frequency = 150, duration = 0.5)
ltas <- sound$to_ltas(bandwidth = 100)
peaks <- ltas$to_spectrum_tier_peaks()
peaks$get_number_of_points()
#> [1] 1
peaks$as_data_frame()
#>   frequency power_db
#> 1  145.5093 70.92279