# Transforms

Fourier transforms, cosine and wavelet transforms, wavelet scattering

DSP System Toolbox™ offers several System objects and blocks to transform streaming time-domain signals into frequency domain, and vice versa. Techniques such as fast Fourier transform (FFT), short-time Fourier transform, high-resolution FFT, wavelet transforms, and the corresponding inverse operations enable you to analyze the signal in either of the domains and have applications in several fields. For an example, see Analyze a Subband of Input Frequencies Using Zoom FFT. For a MathWorks® teaching curriculum module on this topic, see Fourier Analysis (MathWorks Teaching Resources).

DSP System Toolbox also offers the Wavelet Scattering block, which creates a framework for wavelet time scattering in the Simulink® environment. Use this block to derive low-variance features from real-valued data, and then use those features in machine learning and deep learning applications. For more information, see Wavelet Scattering (Wavelet Toolbox). The Wavelet Scattering block requires Wavelet Toolbox™.

## Objekte

 `dsp.FFT` Discrete Fourier transform `dsp.IFFT` Inverse discrete Fourier transform (IDFT) `dsp.ISTFT` Inverse short-time FFT `dsp.STFT` Short-time FFT ```dsp.ZoomFFT ``` High-resolution FFT of a portion of a spectrum

## Blöcke

alle erweitern

 Complex Cepstrum Compute complex cepstrum of input FFT Fast Fourier transform (FFT) of input IFFT Inverse fast Fourier transform (IFFT) of input Inverse Short-Time FFT Recover time-domain signals by performing inverse short-time fast Fourier transform (FFT) Magnitude FFT Compute nonparametric estimate of spectrum using periodogram method Real Cepstrum Compute real cepstrum of input Short-Time FFT Nonparametric estimate of spectrum using short-time fast Fourier transform (STFT) method Zoom FFT High-resolution FFT of a portion of a spectrum
 DCT Discrete cosine transform (DCT) of input DWT Compute discrete wavelet transform (DWT) of input or decompose signals into subbands with smaller bandwidths and slower sample rates IDCT Inverse discrete cosine transform (IDCT) of input IDWT Inverse discrete wavelet transform (IDWT) of input or reconstruct signals from subbands with smaller bandwidths and slower sample rates Wavelet Scattering Model wavelet scattering network in Simulink (Seit R2022b)