Performs the per-element multiplication of two Fourier spectrums

c = cv.mulSpectrums(a, b)
c = cv.mulSpectrums(a, b, 'OptionName',optionValue, ...)

Input

• a first input array.
• b second input array of the same size and type as a.

Output

• c output array of the same size and type as a.

Options

• Rows flag which indicates that each row of a and b is an independent 1D Fourier spectrum. default false
• ConjB optional flag that conjugates the second input array before the multiplication (true) or not (false). default false

The function cv.mulSpectrums performs the per-element multiplication of the two CCS-packed or complex matrices that are results of a real or complex Fourier transform.

The function, together with cv.dft and cv.idft, may be used to calculate convolution (pass ConjB=false) or correlation (pass ConjB=true) of two arrays rapidly. When the arrays are complex, they are simply multiplied (per element) with an optional conjugation of the second-array elements. When the arrays are real, they are assumed to be CCS-packed (see cv.dft for details).