# SPDX-License-Identifier: BSD-3-Clause

menu "Math functions"

config CORDIC_FIXED

bool "Trigonometric functions"

default n

help

Select this to enable sin(), cos(), asin(), acos(),

and cexp() functions as 16 bit and 32 bit versions.

config POWER_FIXED

bool "Power function"

default n

help

This option builds the 32 bit power_int32(). A power represents repeated

multiplication of the same number. power_int32() calculates the power

raised to the base value. The power function works for even, odd and

fractional base and exponent argument.Operating range of power_int32()

with base having values from -32 to + 32 . Exponent values range from

-3 to +3. Power out MIN/MAX range is -/+32768.

config BINARY_LOGARITHM_FIXED

bool "Binary Logarithm function"

default n

help

This option builds Binary Logarithm function (log2n) is the logarithm to

the base 2. The binary logarithm of x is the power to which the number 2

must be raised to obtain the value x. Base 2 logarithm function is implemented

with a short lookup table. (log2n) operates for a range of 32 bit width size

i.e. 1 to 4294967295.

config SQRT_FIXED

bool "Square Root functions"

default n

help

Select this to enable sqrt_int() functions as 16 bit version

to calculate square root.square function having positive number

y as input and return the positive number x multiplied by itself (squared)

config NATURAL_LOGARITHM_FIXED

bool "Natural Logarithm function"

default n

select BINARY_LOGARITHM_FIXED

help

This option builds Natural Logarithm function (loge(N)) which is the logarithm to

the base e.

config COMMON_LOGARITHM_FIXED

bool "Common Logarithm function"

default n

select BINARY_LOGARITHM_FIXED

help

This option builds common Logarithm function (log10(N)) which is the logarithm to

the base 10.

config NUMBERS_NORM

bool "Norm function"

default n

help

Norm function counts the left shifts needed to

normalize integer value.

config NUMBERS_VECTOR_FIND

bool "Find operations for numbers vecter"

default n

help

This option provides functions func_equal_int16(),

find_min_int16(), and find_max_abs32().

config MATH_DECIBELS

bool "Convert decibels to linear"

default n

help

Select this to enable db2lin_fixed() and exp_fixed()

functions.

config MATH_FFT

bool "FFT library"

default n

help

Enable Fast Fourier Transform library, this should not be selected

directly, please select it from other audio components where need it.

menu "Supported FFT word lengths"

visible if MATH_FFT

config MATH_16BIT_FFT

bool "S16_LE data support"

default y

help

This option enables support

for 16 bit PCM data. The twiddle

factors data consumes

4096 bytes.

config MATH_32BIT_FFT

bool "S32_LE data support"

default n

help

This option enables support

for 32 bit PCM data. The twiddle

factors data consumes

8192 bytes.

endmenu

config MATH_FIR

bool "FIR filter library"

default n

help

This option builds FIR (Finite Impulse Response) filter library. It

is selected by components for their digital signal processing. A FIR

filter calculates a convolution of input PCM sample and a configurable

impulse response.

config MATH_IIR_DF2T

bool "IIR DF2T filter library"

default n

help

Select this to build IIR (Infinite Impulse Response) filter

or type 2-transposed library.

config MATH_IIR_DF1

bool "IIR DF1 filter library"

default n

help

Select this to build IIR (Infinite Impulse Response) filter

or type Direct-1 library.

config MATH_WINDOW

bool "Window functions library"

default n

select CORDIC_FIXED

select NATURAL_LOGARITHM_FIXED

help

Select this to build a library for window functions. The window functions

are used to mitigate artefacts (from nature of FFT) to spectra when

computing FFT for a finite long chunk of audio. The sample values within

the window length need to be multiplied by the weight of coefficient value.

The currently provided window functions are Blackman, Hamming, Povey, and

rectangular.

config MATH_MATRIX

bool "Matrix functions library"

default n

help

Select this to build a matrix arithmetic library. Currently it supports

matrix initialization, clear, set values, get values, and a multiply

function for 16 bit fractional format. Multiplication functions exist

for normal matrix multiply and elementwise multiplication.

config MATH_AUDITORY

bool "Auditory functions library"

default n

select NATURAL_LOGARITHM_FIXED

help

Select this to build a psychoacoustics and auditory system related

functions library. Currently the library provides functions for Mel

frequency scale. Functions are provided to convert between Mel and

Hz, initialize a Mel filterbank and apply Mel filterbank to convert

a linear power spectrum into an auditory power spectrum.

menu "Supported Mel filterbank word lengths"

visible if MATH_AUDITORY

config MATH_16BIT_MEL_FILTERBANK

bool "icomplex16 data support"

default n

help

This option enables function psy_apply_mel_filterbank_16().

It takes as input an array of icomplex16

struct data from FFT. Output is 16 bit

logarithmic Mel spectrum.

config MATH_32BIT_MEL_FILTERBANK

bool "icomplex32 data support"

default n

help

This option enables function psy_apply_mel_filterbank_32().

It takes as input an array of icomplex32

struct data from FFT. Output is 16 bit

logarithmic Mel spectrum.

endmenu

config MATH_DCT

bool "DCT transform library"

default n

select MATH_MATRIX

select CORDIC_FIXED

help

Select this to build library for discrete cosine transform

(DCT). The library currently supports initialization of a

matrix for ortho normalized DCT type II. The actual DCT

transform for data is done as matrix multiply with the

returned DCT matrix.

endmenu