Cochleagram

A Praat Cochleagram: the output of a bank of auditory filters modeling the basilar membrane, over time.

Arguments

.xptr: Not for direct use. External pointer to the underlying C++ Cochleagram object; set internally when a method returns a new Cochleagram.

Value

A Cochleagram object.

Details

Frequency runs along the Bark scale (0-25.6 Bark) rather than Hertz, matching the perceptual frequency resolution of the ear. Create one from a Sound with sound$to_cochleagram() or sound$to_cochleagram_edb(); slice it at a time point to get an Excitation pattern, from which loudness can be read off.

Usage


cochleagram <- sound$to_cochleagram()

Query methods

get_start_time(), get_end_time(), get_duration() - time domain in seconds
get_number_of_frames(), get_time_step() - time sampling
get_time_from_column(i_col) - time at a 1-based frame index
get_lowest_frequency(), get_highest_frequency() - frequency range in Bark
get_number_of_frequency_bands(), get_frequency_step() - frequency sampling
get_frequency_from_row() - frequency at a 1-based band index
get_value_at_time_and_frequency(time, freq_bark) - excitation level at a point
get_loudness_at_time(time) - loudness (sone) at a time

Transformation and export

to_excitation(time) - excitation pattern (Excitation object) at a time
get_difference(other, tmin, tmax) - distance between two cochleagrams
as_matrix() - values as a numeric matrix (frequency bands x frames)

Examples

sound <- Sound$create_tone(frequency = 150, duration = 0.3, sampling_rate =
 44100)
cochleagram <- sound$to_cochleagram()
cochleagram$get_duration()
#> [1] 0.3
cochleagram$get_loudness_at_time(0.15)
#> [1] 46.78787