/**
 * Rows 0..n_out-1 of the DCT-II matrix over n_in points
 * (scipy.fft.dct(type=2) semantics: 'ortho' or unnormalized).
 * @returns {Array<Float64Array>} [n_out][n_in]
 */
export function dctBasis(n_in: any, n_out: any, norm?: string): Array<Float64Array>;
/**
 * MFCC cepstral core: DCT-II along the mel axis of a LOG-power mel
 * spectrogram, keep the first n_mfcc rows, optional cepstral liftering
 * (1 + (L/2)·sin(π(k+1)/L)).
 * @param {Array} logMel - [n_mels][n_frames] log-power mel spectrogram
 * @returns {Array<Float64Array>} [n_mfcc][n_frames]
 */
export function mfccFromLogMel(logMel: any[], { n_mfcc, dct_type, norm, lifter }?: {
    n_mfcc?: number;
    dct_type?: number;
    norm?: string;
    lifter?: number;
}): Array<Float64Array>;