imageStats.cpp File Reference

Image analysis and statistic function declaration. This file is part of the DDT Image Handling Library and provides functions to analyse and calculate statistic values for CPL images. More...

#include "ddt/imageStats.hpp"
#include <cmath>
#include <iostream>
#include "ddt/imageError.hpp"

Functions
double	MaxPixelCplImage (const cpl_image *const image)
double	MaxPixelCplImageWindow (const cpl_image *const image, const int llx, const int lly, const int urx, const int ury)
double	MinPixelCplImage (const cpl_image *const image)
double	MinPixelCplImageWindow (const cpl_image *const image, const int llx, const int lly, const int urx, const int ury)
double	MedianPixelCplImage (const cpl_image *const image)
double	MeanPixelCplImage (const cpl_image *const image)
double	MeanPixelCplImageWindow (const cpl_image *const image, const int llx, const int lly, const int urx, const int ury)
double	RmsValueCplImage (const cpl_image *const image)
double	RmsValueCplImageWindow (const cpl_image *const image, const int llx, const int lly, const int urx, const int ury)
cpl_stats *	StatsCplImage (const cpl_image *const image)
cpl_stats *	StatsCplImageWindow (const cpl_image *const image, const int llx, const int lly, const int urx, const int ury)
double	RmsValueCplStats (const cpl_stats *const stats_cpl)
CplStatistics *	StatisticsCplImage (const cpl_image *const image)
CplStatistics *	StatisticsCplImageWindow (const cpl_image *const image, const int llx, const int lly, const int urx, const int ury)
CplStatistics *	StatisticsCplStats (const cpl_stats *const stats_cpl)
bool	FwhmValuesCplImage (const cpl_image *const image, const int x_pos, const int y_pos, double *const fwhm_x, double *const fwhm_y)
cpl_apertures *	AperturesCplImage (const cpl_image *const image, const double sigma)
bool	AperturesCplImageDump (const char *const file_name, const cpl_apertures *const apertures)
bool	MinMaxPixelsCplImage (const cpl_image *const image, double *const min, double *const max)
bool	MedianMinMaxPixelsCplImage (const cpl_image *const image, double *const min, double *const max, const double kernel_size)
void	CheckForNanValues (cpl_image *const image)
double	PixelValueCplImage (const cpl_image *const image, const int x_pos, const int y_pos, int *const is_rejected)
void	GetHistogram (const cpl_image *const image, const int64_t min_value, const int64_t max_value, std::vector< int > &distribution)
void	GetHistogramBins (const cpl_image *const image, const int64_t min_value, const int64_t max_value, std::vector< int > &distribution)
void	GetCutValuesPercentage (const cpl_image *const image, const double percentage, double *const min_value, double *const max_value)
bool	GetIQEValues (const cpl_image *const subImage, double *const x_axis_angle, double *const background, double *const peak_above_background, double *const fwhm_x, double *const fwhm_y, double *const object_coord_x, double *const object_coord_y)
bool	MinMaxInvalidCheck (const cpl_image *const image, double *const min, double *const max)
double	SigmaCplImage (const cpl_image *const image, double *const sigma)
double	SigmaCplImageWindow (const cpl_image *const image, const int llx, const int lly, const int urx, const int ury, double *const sigma)

Detailed Description

Image analysis and statistic function declaration. This file is part of the DDT Image Handling Library and provides functions to analyse and calculate statistic values for CPL images.

Copyright

(c) Copyright ESO 2020 All Rights Reserved ESO (eso.org) is an Intergovernmental Organization, and therefore special legal conditions apply.

Author

Christoph Bortlisz, CGI

Since

2020/07/29

Function Documentation

AperturesCplImage()

cpl_apertures * AperturesCplImage	(	const cpl_image *const	image,
		const double	sigma )

Detect apertures in a CPL image.

Parameters

image	CPL image object
sigma	detection level

Returns

cpl_apertures list of apertures detected in the CPL image

AperturesCplImageDump()

bool AperturesCplImageDump	(	const char *const	file_name,
		const cpl_apertures *const	apertures )

Dump list of apertures from a CPL image into a file.

Parameters

file_name	Filename of the output file
apertures	list of apertures

Returns

bool indicating success of dumping

CheckForNanValues()

void CheckForNanValues

(

cpl_image *const

image

)

Check the pixel values of a CPL image for NaN values. These are then rejected in the image.

Parameters

image

CPL image object

FwhmValuesCplImage()

bool FwhmValuesCplImage	(	const cpl_image *const	image,
		const int	x_pos,
		const int	y_pos,
		double *const	fwhm_x,
		double *const	fwhm_y )

Compute FWHM (full width half maximum) values in x and y direction.

Parameters

image	CPL image object
x_pos	the x position
y_pos	the y position
fwhm_x	the computed FWHM value in x (-1 on error)
fwhm_y	the computed FWHM value in y (-1 on error)

Returns

bool indicating success of computing

GetCutValuesPercentage()

void GetCutValuesPercentage	(	const cpl_image *const	image,
		const double	percentage,
		double *const	min_value,
		double *const	max_value )

Get the min/max values from a CPL image, given a percentage of pixel that fall inside this range

Parameters

image	CPL image object
percentage	the percentage of pixel values to fall inside the min/max range
min_value	the resulting minimum pixel value
max_value	the resulting maximum pixel value

GetHistogram()

void GetHistogram	(	const cpl_image *const	image,
		const int64_t	min_value,
		const int64_t	max_value,
		std::vector< int > &	distribution )

Get the histogram (pixel value distribution) for a CPL image

Parameters

image	CPL image object
min_value	the minimum pixel value to consider for the histogram
max_value	the maximum pixel value to consider for the histogram
distribution	vector containing the pixel value distribution

GetHistogramBins()

void GetHistogramBins	(	const cpl_image *const	image,
		const int64_t	min_value,
		const int64_t	max_value,
		std::vector< int > &	distribution )

Get the histogram (pixel value distribution) for a CPL image. The distribution vector is reshaped into bins. The bin size and count are calculated automatically.

Parameters

image	CPL image object
min_value	the minimum pixel value to consider for the histogram
max_value	the maximum pixel value to consider for the histogram
distribution	vector containing the pixel value distribution

GetIQEValues()

bool GetIQEValues	(	const cpl_image *const	sub_image,
		double *const	x_axis_angle,
		double *const	background,
		double *const	peak_above_background,
		double *const	fwhm_x,
		double *const	fwhm_y,
		double *const	object_coord_x,
		double *const	object_coord_y )

Get the image quality estimation values from a CPL image. The CPL image is casted to a float values image internally before the values are calculated.

Parameters

subImage	CPL image object
x_axis_angle	the resulting angle of the major axis with the horizontal in degrees
background	the resulting background computed
peak_above_background	the peak value of the
fwhm_x	the resulting FWHM along the major axis
fwhm_y	the resulting FWHM along the minor axis
object_coord_x	x coordinate of the center of the detected object
object_coord_y	y coordinate of the center of the detected object

Returns

true if computation was successful, false otherwise

MaxPixelCplImage()

double MaxPixelCplImage

(

const cpl_image *const

image

)

This file is part of the DDT Image Handling Library and provides functions to analyse and calculate statistic values for CPL images. Calculate maximum pixel value of a CPL image.

Parameters

image

CPL image object

Returns

double the maximum pixel value in the CPL image

MaxPixelCplImageWindow()

double MaxPixelCplImageWindow	(	const cpl_image *const	image,
		const int	llx,
		const int	lly,
		const int	urx,
		const int	ury )

Calculate maximum pixel value of a CPL image sub-window.

Parameters

image	CPL image sub-window object
llx	lower left x position (1: leftmost)
lly	lower left y position (1: lowest)
urx	upper right x position
ury	upper right y position

Returns

double the maximum pixel value in the CPL image sub-window

MeanPixelCplImage()

double MeanPixelCplImage

(

const cpl_image *const

image

)

Calculate mean pixel value of a CPL image.

Parameters

image

CPL image object

Returns

double the mean pixel value in the CPL image

MeanPixelCplImageWindow()

double MeanPixelCplImageWindow	(	const cpl_image *const	image,
		const int	llx,
		const int	lly,
		const int	urx,
		const int	ury )

Calculate mean pixel value of a CPL image sub-window.

Parameters

image	CPL image sub-window object
llx	lower left x position (1: leftmost)
lly	lower left y position (1: lowest)
urx	upper right x position
ury	upper right y position

Returns

double the mean pixel value in the CPL image sub-window

MedianMinMaxPixelsCplImage()

bool MedianMinMaxPixelsCplImage	(	const cpl_image *const	image,
		double *const	min,
		double *const	max,
		const double	kernel_size )

Get min / max values from a median filtered CPL image.

Parameters

image	CPL image object
min	the minimum pixel value, or -1.0 on error
max	the maximum pixel value, or -1.0 on error
kernel_size	size of filtering kernel; e.g. a value of 5 results in a 5x5 kernel matrix; defaults to 5

Returns

bool indicating success of getting min / max values

MedianPixelCplImage()

double MedianPixelCplImage

(

const cpl_image *const

image

)

Calculate median pixel value of a CPL image.

Parameters

image

CPL image object

Returns

double the median pixel value in the CPL image

MinMaxInvalidCheck()

bool MinMaxInvalidCheck	(	const cpl_image *const	image,
		double *const	min,
		double *const	max )

Get the min/max values from a CPL image. This function checks if the found values are invalid (NaN). In this case, the min/max computation is repeated, but with all NaN values in the image being rejected.

Parameters

image	CPL image object
min	the resulting minimum pixel value, or -1.0 on error
max	the resulting maximum pixel value, or -1.0 on error

Returns

true if computation was successful, false otherwise

MinMaxPixelsCplImage()

bool MinMaxPixelsCplImage	(	const cpl_image *const	image,
		double *const	min,
		double *const	max )

Get min / max values from a CPL image.

Parameters

image	CPL image object
min	the minimum pixel value, or -1.0 on error
max	the maximum pixel value, or -1.0 on error

Returns

bool indicating success of getting min / max values

MinPixelCplImage()

double MinPixelCplImage

(

const cpl_image *const

image

)

Calculate minimum pixel value of an CPL image.

Parameters

image

CPL image object

Returns

double the minimum pixel value in the CPL image

MinPixelCplImageWindow()

double MinPixelCplImageWindow	(	const cpl_image *const	image,
		const int	llx,
		const int	lly,
		const int	urx,
		const int	ury )

Calculate minimum pixel value of a CPL image sub-window.

Parameters

image	CPL image sub-window object
llx	lower left x position (1: leftmost)
lly	lower left y position (1: lowest)
urx	upper right x position
ury	upper right y position

Returns

double the minimum pixel value in the CPL image sub-window

PixelValueCplImage()

double PixelValueCplImage	(	const cpl_image *const	image,
		const int	x_pos,
		const int	y_pos,
		int *const	is_rejected )

Get the pixel value at a certain image position

Parameters

image	CPL image object
x_pos	the pixel x position
y_pos	the pixel y position
is_rejected	set to 1 if the pixel is bad, 0 if good, or -1 on error

Returns

double pixel value (cast to double) or undefined

RmsValueCplImage()

double RmsValueCplImage

(

const cpl_image *const

image

)

Calculate RMS (root mean square) value of a CPL image.

Parameters

image

CPL image object

Returns

double the RMS value of the CPL image, or 0.0 in case of errors

RmsValueCplImageWindow()

double RmsValueCplImageWindow	(	const cpl_image *const	image,
		const int	llx,
		const int	lly,
		const int	urx,
		const int	ury )

Calculate RMS (root mean square) value of a CPL image sub-window.

Parameters

image	CPL image sub-window object
llx	lower left x position (1: leftmost)
lly	lower left y position (1: lowest)
urx	upper right x position
ury	upper right y position

Returns

double the RMS value of the CPL image sub-window, or 0.0 in case of errors

RmsValueCplStats()

double RmsValueCplStats

(

const cpl_stats *const

stats_cpl

)

Calculate RMS (root mean square) value from statistic values contained in a cpl_stats object.

Parameters

stats_cpl

cpl_stats object

Returns

double the RMS value, or 0.0 in case of errors

SigmaCplImage()

double SigmaCplImage	(	const cpl_image *const	image,
		double *const	sigma )

Calculate the median and the median absolute deviation (sigma) of a CPL image.

Parameters

image	CPL image object
sigma	the resulting median absolute deviation of the CPL image

Returns

double the median of the CPL image

SigmaCplImageWindow()

double SigmaCplImageWindow	(	const cpl_image *const	image,
		const int	llx,
		const int	lly,
		const int	urx,
		const int	ury,
		double *const	sigma )

Calculate the median and the median absolute deviation (sigma) of a CPL image sub-window.

Parameters

image	CPL image sub-window object
llx	lower left x position (1: leftmost)
lly	lower left y position (1: lowest)
urx	upper right x position
ury	upper right y position
sigma	the resulting median absolute deviation of the CPL image

Returns

double the median of the CPL image

StatisticsCplImage()

CplStatistics * StatisticsCplImage

(

const cpl_image *const

image

)

Get statistics from CPL image

Parameters

image

CPL image object

Returns

CplStatistics structure containing statistic values or NULL in case of errors Following values are contained: number of pixels, min pixel value, max pixel value, mean pixel value, rms value

StatisticsCplImageWindow()

CplStatistics * StatisticsCplImageWindow	(	const cpl_image *const	image,
		const int	llx,
		const int	lly,
		const int	urx,
		const int	ury )

Get statistics from CPL image sub-window

Parameters

image	CPL image object
llx	lower left x position (1: leftmost)
lly	lower left y position (1: lowest)
urx	upper right x position
ury	upper right y position

Returns

CplStatistics structure containing statistic values or NULL in case of errors Following values are contained: number of pixels, min pixel value, max pixel value, mean pixel value, rms value

StatisticsCplStats()

CplStatistics * StatisticsCplStats

(

const cpl_stats *const

stats_cpl

)

Get statistics from statistic values contained in a cpl_stats object.

Parameters

stats_cpl

cpl_stats object

Returns

CplStatistics structure containing statistic values or NULL in case of errors Following values are contained: number of pixels, min pixel value, max pixel value, mean pixel value, rms value, median value

StatsCplImage()

cpl_stats * StatsCplImage

(

const cpl_image *const

image

)

Get statistics from CPL image

Parameters

image

CPL image object

Returns

cpl_stats structure containing CPL statistic values or NULL in case of errors

StatsCplImageWindow()

cpl_stats * StatsCplImageWindow	(	const cpl_image *const	image,
		const int	llx,
		const int	lly,
		const int	urx,
		const int	ury )

Get statistics from CPL image sub-window

Parameters

image	CPL image sub-window object
llx	lower left x position (1: leftmost)
lly	lower left y position (1: lowest)
urx	upper right x position
ury	upper right y position

Returns

cpl_stats structure containing CPL statistic values or NULL in case of errors