getRateChangeFactors

Get overall interpolation and decimation factors

Syntax

[L,M] = getRateChangeFactors(rateConverter)

Description

[L,M] = getRateChangeFactors(rateConverter) returns the overall interpolation factor, L, and the overall decimation factor, M, corresponding to the rateConverter. The rate converter object can be a dsp.FarrowRateConverter System object™ or a dsp.SampleRateConverter System object. The rate change factors computed take into account the OutputRateTolerance property.

In the case of dsp.SampleRateConverter, the overall decimation factor affects the allowable frame size of the input to the object. The row length of the input vector or matrix to the dsp.SampleRateConverter object must be an integer multiple of M.

This function supports C and C++ code generation.

Examples

Return Resampling Factors of dsp.FarrowRateConverter

Create a default dsp.FarrowRateConverter object that converts a signal from 44.1 kHz to 48 kHz.

frc = dsp.FarrowRateConverter

frc = 
  dsp.FarrowRateConverter with properties:

   Main
        InputSampleRate: 44100
       OutputSampleRate: 48000
    OutputRateTolerance: 0
          Specification: 'Polynomial order'
        PolynomialOrder: 3

  Show all properties

Return the overall interpolation (L) and decimation (M) factors of the filter object.

[L,M] = getRateChangeFactors(frc)

L = 160

M = 147

Default Resampling Factors

Create src, a multistage sample rate converter with default properties. src combines three filter stages to convert from 192 kHz to 44.1 kHz. Determine its overall interpolation and decimation factors.

src = dsp.SampleRateConverter;
[L,M] = getRateChangeFactors(src)

L = 147

M = 640

Input Arguments

rateConverter — Sample rate conversion filter

dsp.FarrowRateConverter | dsp.SampleRateConverter

Polynomial sample rate conversion filter, specified as a dsp.FarrowRateConverter or a dsp.SampleRateConverter System object.

Output Arguments

L — Overall interpolation factor

scalar

Overall interpolation factor, returned as a scalar.

Data Types: double

M — Overall decimation factor

scalar

Overall decimation factor, returned as a scalar. In the case of dsp.SampleRateConverter, the overall decimation factor affects the allowable frame size of the input to the object. The row length of the input vector or matrix to the dsp.SampleRateConverter object must be an integer multiple of M.

Data Types: double