ev::EventHistogram_< T, Options, E > Class Template Reference

This class extends ev::EventImage_<T> for event 2D histograms. More...

#include <event-histogram.hpp>

Inheritance diagram for ev::EventHistogram_< T, Options, E >:

Public Member Functions
template<typename... Args>
	EventHistogram_ (Args &&...args)
cv::Mat &	render ()
	Render event histogram matrix.
void	setOutlierRejection (const double k)
	Saturate the pixels whose count is abnormally high when rendering.
Public Member Functions inherited from ev::EventImage_< T, RepresentationOptions::NONE, int >
	EventImage_ (Args &&...args)
cv::Mat &	render ()
Public Member Functions inherited from ev::AbstractRepresentation_< T, Options, int >
std::size_t	count () const
	Number of events integrated in the representation.
TimeType	firstTimestamp () const
	Timestamp of the oldest event integrated in the representation.
TimeType	lastTimestamp () const
	Timestamp of the newest event integrated in the representation.
void	clear ()
	Remove all events from the representation.
bool	insert (const Event_< int > &e)
	Insert one event in the representation.
void	setTimeOffset (const Event_< int > &e)
	Set time offset.
void	setValue (const bool polarity, const Type &value)
	Set values for ON and OFF pixels.
void	setValues (const Type &positive, const Type &negative, const Type &reset)
	Set values for ON, OFF, and non-activated pixels.
void	setColor (const bool polarity, const cv::viz::Color &color)
	Set colors for ON and OFF pixels. For more information, please refer here.
void	setColors (const cv::viz::Color &positive, const cv::viz::Color &negative, const cv::viz::Color &reset)
	Set colors for ON, OFF, and non-activated pixels. For more information, please refer here.
void	setColormap (const cv::ColormapTypes cm)
	Set colormap for the representation.
Public Member Functions inherited from ev::Stats_< AbstractRepresentation_< T, Options, int > >
ResultType	duration () const
	Time difference between the last and the first event.
ResultType	rate () const
	Compute event rate as the ratio between the number of events and the time difference between the last and the first event.
ResultType	density (const cv::Size size) const
	Compute event density as the ratio between the number of events and the number of pixels.
std::size_t	activePixels () const
	Count the pixels with at least one event.
ResultType	fillRatio (const cv::Size size) const
	Compute fill ratio as the fraction of pixels with at least one event.
ResultType	polarityRatio (const PolarityType p) const
	Compute polarity ratio as the fraction of events with the given polarity.
Event_< ResultType >	mean () const
	Compute the mean of the events.
cv::Point_< ResultType >	meanPoint () const
	Compute the mean x,y point of the events.
cv::Matx< ResultType, 2, 2 >	covariance () const
	Compute the covariance of the x,y coordinates of the events around meanPoint().
cv::Rect	boundingBox () const
	Compute the smallest rectangle of pixels containing the events.
ResultType	meanTime () const
	Compute the mean time of the events.
ResultType	midTime () const
	Calculate the midpoint time between the oldest and the newest event.
std::size_t	peak () const
	Find the largest number of events on a single pixel.
ResultType	entropy () const
	Compute the Shannon entropy of the spatial distribution of the events.

Public Attributes
Mat::Counter	counter {cv::Mat_<int>(EventImage_<T, Options, E>::size())}

Additional Inherited Members
Public Types inherited from ev::AbstractRepresentation_< T, Options, int >
using	Type
Public Types inherited from ev::Stats_< AbstractRepresentation_< T, Options, int > >
using	ResultType

Detailed Description

template<typename T, const RepresentationOptions Options = RepresentationOptions::NONE, typename E = int>
class ev::EventHistogram_< T, Options, E >

This class extends ev::EventImage_<T> for event 2D histograms.

Analogously to OpenCV library, the following aliases are defined for convenience:

using EventHistogram1b = EventHistogram_<uchar>;
using EventHistogram3b = EventHistogram_<cv::Vec3b>;
using EventHistogram1s = EventHistogram_<short>;
using EventHistogram3s = EventHistogram_<cv::Vec3s>;
using EventHistogram1w = EventHistogram_<ushort>;
using EventHistogram3w = EventHistogram_<cv::Vec3w>;
using EventHistogram1i = EventHistogram_<int>;
using EventHistogram3i = EventHistogram_<cv::Vec3i>;
using EventHistogram1f = EventHistogram_<float>;
using EventHistogram3f = EventHistogram_<cv::Vec3f>;
using EventHistogram1d = EventHistogram_<double>;
using EventHistogram3d = EventHistogram_<cv::Vec3d>;
using EventHistogram1 = EventHistogram1b;
using EventHistogram3 = EventHistogram3b;
using EventHistogram = EventHistogram1;

Member Function Documentation

render()

template<typename T, const RepresentationOptions Options = RepresentationOptions::NONE, typename E = int>

cv::Mat & ev::EventHistogram_< T, Options, E >::render

(

)

Render event histogram matrix.

Event histogram matrix is generated from counter matrix.

setOutlierRejection()

template<typename T, const RepresentationOptions Options = RepresentationOptions::NONE, typename E = int>

void ev::EventHistogram_< T, Options, E >::setOutlierRejection ( const double k )

inline

Saturate the pixels whose count is abnormally high when rendering.

Parameters

k	Median absolute deviations above the median at which a pixel is considered an outlier.

Note

A pixel with count \( C_{i,j} \) saturates when \( |C_{i,j}| > \mathrm{median}(C) + 1.4826 \, k \, \mathrm{MAD}(C) \).

Member Data Documentation

counter

template<typename T, const RepresentationOptions Options = RepresentationOptions::NONE, typename E = int>

Mat::Counter ev::EventHistogram_< T, Options, E >::counter {cv::Mat_<int>(EventImage_<T, Options, E>::size())}

Event counter

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The documentation for this class was generated from the following file:

• modules/representations/include/openev/representations/event-histogram.hpp