Fourier transform functions

Detailed Description

Collaboration diagram for Fourier transform functions:

Functions
void BASE_IMPEXP	mrpt::math::fft_real (CVectorFloat &in_realData, CVectorFloat &out_FFT_Re, CVectorFloat &out_FFT_Im, CVectorFloat &out_FFT_Mag)
	Computes the FFT of a 2^N-size vector of real numbers, and returns the Re+Im+Magnitude parts. More...
void BASE_IMPEXP	mrpt::math::dft2_real (const CMatrixFloat &in_data, CMatrixFloat &out_real, CMatrixFloat &out_imag)
	Compute the 2D Discrete Fourier Transform (DFT) of a real matrix, returning the real and imaginary parts separately. More...
void BASE_IMPEXP	mrpt::math::idft2_real (const CMatrixFloat &in_real, const CMatrixFloat &in_imag, CMatrixFloat &out_data)
	Compute the 2D inverse Discrete Fourier Transform (DFT) More...
void BASE_IMPEXP	mrpt::math::dft2_complex (const CMatrixFloat &in_real, const CMatrixFloat &in_imag, CMatrixFloat &out_real, CMatrixFloat &out_imag)
	Compute the 2D Discrete Fourier Transform (DFT) of a complex matrix, returning the real and imaginary parts separately. More...
void BASE_IMPEXP	mrpt::math::idft2_complex (const CMatrixFloat &in_real, const CMatrixFloat &in_imag, CMatrixFloat &out_real, CMatrixFloat &out_imag)
	Compute the 2D inverse Discrete Fourier Transform (DFT). More...
void BASE_IMPEXP	mrpt::math::cross_correlation_FFT (const CMatrixFloat &A, const CMatrixFloat &B, CMatrixFloat &out_corr)
	Correlation of two matrixes using 2D FFT. More...

Function Documentation

cross_correlation_FFT()

void mrpt::mrpt::math::cross_correlation_FFT	(	const CMatrixFloat &	A,
		const CMatrixFloat &	B,
		CMatrixFloat &	out_corr
	)

Correlation of two matrixes using 2D FFT.

Definition at line 1991 of file math.cpp.

References ASSERT_, mrpt::math::dft2_complex(), mrpt::math::idft2_complex(), MRPT_END, MRPT_START, mrpt::math::round2up(), mrpt::math::square(), and THROW_EXCEPTION.

dft2_complex()

void mrpt::math::dft2_complex	(	const CMatrixFloat &	in_real,
		const CMatrixFloat &	in_imag,
		CMatrixFloat &	out_real,
		CMatrixFloat &	out_imag
	)

Compute the 2D Discrete Fourier Transform (DFT) of a complex matrix, returning the real and imaginary parts separately.

Parameters

in_real	The N_1xN_2 matrix with the real part.
in_imag	The N_1xN_2 matrix with the imaginary part.
out_real	The N_1xN_2 output matrix which will store the real values (user has not to initialize the size of this matrix).
out_imag	The N_1xN_2 output matrix which will store the imaginary values (user has not to initialize the size of this matrix). If the dimensions of the matrix are powers of two, the fast fourier transform (FFT) is used instead of the general algorithm.

See also

fft_real, idft2_complex,dft2_real

Definition at line 1451 of file math.cpp.

References ASSERT_, mrpt::math::cdft2d(), MRPT_END, MRPT_START, myGeneralDFT(), and mrpt::math::round2up().

Referenced by mrpt::math::cross_correlation_FFT(), and mrpt::utils::CImage::cross_correlation_FFT().

dft2_real()

void mrpt::math::dft2_real	(	const CMatrixFloat &	in_data,
		CMatrixFloat &	out_real,
		CMatrixFloat &	out_imag
	)

Compute the 2D Discrete Fourier Transform (DFT) of a real matrix, returning the real and imaginary parts separately.

Parameters

in_data	The N_1xN_2 matrix.
out_real	The N_1xN_2 output matrix which will store the real values (user has not to initialize the size of this matrix).
out_imag	The N_1xN_2 output matrix which will store the imaginary values (user has not to initialize the size of this matrix).

See also

fft_real, ifft2_read, fft2_complex If the dimensions of the matrix are powers of two, the fast fourier transform (FFT) is used instead of the general algorithm.

Definition at line 1186 of file math.cpp.

References MRPT_END, MRPT_START, and mrpt::math::rdft2d().

fft_real()

void mrpt::math::fft_real	(	CVectorFloat &	in_realData,
		CVectorFloat &	out_FFT_Re,
		CVectorFloat &	out_FFT_Im,
		CVectorFloat &	out_FFT_Mag
	)

Computes the FFT of a 2^N-size vector of real numbers, and returns the Re+Im+Magnitude parts.

See also

fft2_real

Definition at line 1004 of file math.cpp.

References mrpt::system::os::memcpy(), MRPT_END, MRPT_START, mrpt::math::realft(), and mrpt::math::square().

idft2_complex()

void mrpt::math::idft2_complex	(	const CMatrixFloat &	in_real,
		const CMatrixFloat &	in_imag,
		CMatrixFloat &	out_real,
		CMatrixFloat &	out_imag
	)

Compute the 2D inverse Discrete Fourier Transform (DFT).

Parameters

in_real	The N_1xN_2 input matrix with real values, where both dimensions MUST BE powers of 2.
in_imag	The N_1xN_2 input matrix with imaginary values, where both dimensions MUST BE powers of 2.
out_real	The N_1xN_2 output matrix for real part (user has not to initialize the size of this matrix).
out_imag	The N_1xN_2 output matrix for imaginary part (user has not to initialize the size of this matrix).

See also

fft_real, dft2_real,dft2_complex If the dimensions of the matrix are powers of two, the fast fourier transform (FFT) is used instead of the general algorithm.

Definition at line 1560 of file math.cpp.

References ASSERT_, mrpt::math::cdft2d(), MRPT_END, MRPT_START, myGeneralDFT(), and mrpt::math::round2up().

Referenced by mrpt::math::cross_correlation_FFT(), and mrpt::utils::CImage::cross_correlation_FFT().

idft2_real()

void mrpt::math::idft2_real	(	const CMatrixFloat &	in_real,
		const CMatrixFloat &	in_imag,
		CMatrixFloat &	out_data
	)

Compute the 2D inverse Discrete Fourier Transform (DFT)

Parameters

in_real	The N_1xN_2 input matrix with real values.
in_imag	The N_1xN_2 input matrix with imaginary values.
out_data	The N_1xN_2 output matrix (user has not to initialize the size of this matrix). Note that the real and imaginary parts of the FFT will NOT be checked to assure that they represent the transformation of purely real data. If the dimensions of the matrix are powers of two, the fast fourier transform (FFT) is used instead of the general algorithm.

See also

fft_real, fft2_real

Definition at line 1286 of file math.cpp.

References ASSERT_, MRPT_END, MRPT_START, mrpt::math::rdft2d(), mrpt::math::round2up(), and THROW_EXCEPTION.