* To calculate magnitude and angle in degrees :ocv:func:`cvCartToPolar` is used internally thus angles are measured from 0 to 360 with accuracy about 0.3 degrees.
* An example using the LinearPolar operation can be found at opencv_source_code/samples/c/polar_transforms.c
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@@ -319,11 +333,11 @@ Remaps an image to log-polar space.
:param src: Source image
:param dst: Destination image
:param dst: Destination image. It will have same size and type as src.
:param center: The transformation center; where the output precision is maximal
:param M: Magnitude scale parameter. See below
:param M: Magnitude scale parameter. It determines the radius of the bounding circle to transform too. See below
:param flags: A combination of interpolation methods and the following optional flags:
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@@ -338,7 +352,7 @@ The function ``cvLogPolar`` transforms the source image using the following tran
.. math::
dst( \phi , \rho ) = src(x,y)
dst( \rho , \phi ) = src(x, y)
*
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@@ -346,20 +360,36 @@ The function ``cvLogPolar`` transforms the source image using the following tran
.. math::
dst(x,y) = src( \phi , \rho )
dst(x,y) = src( \rho , \phi )
where
.. math::
\rho = M \cdot \log{\sqrt{x^2 + y^2}} , \phi =atan(y/x)
\begin{array}{l}
I = (dx,dy) = (x - center.x,y - center.y) \\
\rho = M \cdot log_e(\texttt{magnitude} (I)) ,\\
\phi = Ky \cdot \texttt{angle} (I)_{0..360 deg}
\end{array}
and
The function emulates the human "foveal" vision and can be used for fast scale and rotation-invariant template matching, for object tracking and so forth. The function can not operate in-place.
.. math::
\begin{array}{l}
M = src.cols / log_e(maxRadius) \\
Ky = src.rows / 360
\end{array}
The function emulates the human "foveal" vision and can be used for fast scale and rotation-invariant template matching, for object tracking and so forth.
.. note::
* The function can not operate in-place.
* To calculate magnitude and angle in degrees :ocv:func:`cvCartToPolar` is used internally thus angles are measured from 0 to 360 with accuracy about 0.3 degrees.
* An example using the geometric logpolar operation in 4 applications can be found at opencv_source_code/samples/cpp/logpolar_bsm.cpp