Algorithms to detect bad-pixels on a sequence of images like e.g. domeflats. More...

Collaboration diagram for Bad Pixel Mask via fitting:

Functions
hdrl_parameter *	hdrl_bpm_fit_parameter_create_pval (int degree, double pval)
	create bpm_fit parameter with p-value bpm treshold

hdrl_parameter *	hdrl_bpm_fit_parameter_create_rel_chi (int degree, double rel_chi_low, double rel_chi_high)
	create bpm_fit parameter with relative chi bpm treshold

hdrl_parameter *	hdrl_bpm_fit_parameter_create_rel_coef (int degree, double rel_coef_low, double rel_coef_high)
	create bpm_fit parameter with relative coefficient bpm treshold

cpl_boolean	hdrl_bpm_fit_parameter_check (const hdrl_parameter *self)
	Check that the parameter is a bpm_fit parameter.

cpl_error_code	hdrl_bpm_fit_parameter_verify (const hdrl_parameter *p)
	verify that the parameter is a valid bpm_fit_parameter

int	hdrl_bpm_fit_parameter_get_degree (const hdrl_parameter *p)
	get degree of polynomial fit of parameter

double	hdrl_bpm_fit_parameter_get_pval (const hdrl_parameter *p)
	get p-value bpm treshold

double	hdrl_bpm_fit_parameter_get_rel_chi_low (const hdrl_parameter *p)
	get relative chi distribution lower threshold

double	hdrl_bpm_fit_parameter_get_rel_chi_high (const hdrl_parameter *p)
	get relative chi distribution upper threshold

double	hdrl_bpm_fit_parameter_get_rel_coef_low (const hdrl_parameter *p)
	get relative fit coefficient distribution lower threshold

double	hdrl_bpm_fit_parameter_get_rel_coef_high (const hdrl_parameter *p)
	get relative fit coefficient distribution upper threshold

cpl_parameterlist *	hdrl_bpm_fit_parameter_create_parlist (const char base_context, const char prefix, const hdrl_parameter *defaults)
	Create a parameter list for the BPM_FIT computation.

hdrl_parameter *	hdrl_bpm_fit_parameter_parse_parlist (const cpl_parameterlist parlist, const char prefix)
	Parse a parameterlist to create input parameters for the BPM_FIT.

cpl_error_code	hdrl_bpm_fit_compute (const hdrl_parameter par, const hdrl_imagelist data, const cpl_vector sample_pos, cpl_image *out_mask)
	compute bad pixel map based on fitting a stack of images

Detailed Description

Algorithms to detect bad-pixels on a sequence of images like e.g. domeflats.

The routine in this module derives bad pixels on a sequence of images (e.g. domeflats with differend exposure time). The algorithm fits a polynomial to each pixel-sequence and determinates bad pixels based on this fit and various thresholding methods.

The calculation is performed by calling the top-level function hdrl_bpm_fit_compute() and the parameters passed to this function can be created by calling hdrl_bpm_fit_parameter_create_rel_chi(), or hdrl_bpm_fit_parameter_create_rel_coef(), or hdrl_bpm_fit_parameter_create_pval(), depending on the method one would like to use.

Function Documentation

◆ hdrl_bpm_fit_compute()

cpl_error_code hdrl_bpm_fit_compute	(	const hdrl_parameter *	par,
		const hdrl_imagelist *	data,
		const cpl_vector *	sample_pos,
		cpl_image **	out_mask
	)

compute bad pixel map based on fitting a stack of images

Parameters

par	input bpm_fit_parameter
data	hdrl_imagelist to fit
sample_pos	cpl_vector of sampling position of the images in data, e.g. exposure time
out_mask	output bad pixel mask as integer image

Returns: CPL_ERROR_NONE if everything is ok, an error code otherwise

The function fits a polynomial of degree degree to the imagelist at the sampling positions defined in sample_pos.

Three methods are available to convert the information from the fit into a bad pixel map:

Relative cutoff on the chi distribution of all fits. Pixels with chi values strictly outside the interval $mean(\chi) - stdev(\chi) \times rel\_chi\_low$ and $mean(\chi) + stdev(\chi) \times rel\_chi\_high$ are considered bad. The corresponding hdrl parameter is created by hdrl_bpm_fit_parameter_create_rel_chi()

Relative cutoff on the distribution of the fit coefficients. Pixels with fit coefficients strictly outside the interval $mean(coef) - stdev(coef) \times rel\_coef\_low$ and $mean(coef) + stdev(coef) \times rel\_coef\_high$ are considered bad. The coefficient numbers that caused the pixel to be marked as bad are encoded as powers of two of their degree (starting from 0). The corresponding hdrl parameter is created by hdrl_bpm_fit_parameter_create_rel_coef()

Pixels with low p-value. When the errors of the pixels are correct the p-value can be interpreted as the probability with which the pixel response fits the chosen model. The corresponding hdrl parameter is created by hdrl_bpm_fit_parameter_create_pval()

◆ hdrl_bpm_fit_parameter_check()

cpl_boolean hdrl_bpm_fit_parameter_check ( const hdrl_parameter * self )

Check that the parameter is a bpm_fit parameter.

Parameters

self	The parameter to check

Returns: True or False

◆ hdrl_bpm_fit_parameter_create_parlist()

cpl_parameterlist * hdrl_bpm_fit_parameter_create_parlist	(	const char *	base_context,
		const char *	prefix,
		const hdrl_parameter *	defaults
	)

Create a parameter list for the BPM_FIT computation.

Parameters

base_context	base context of parameter (e.g. recipe name)
prefix	prefix of parameter, may be empty string
defaults	default values

Creates a parameterlist with the BPM_FIT parameters:

base_context.prefix.degree
base_context.prefix.pval
base_context.prefix.rel-chi-low
base_context.prefix.rel-chi-high
base_context.prefix.rel-coef-low
base_context.prefix.rel-coef-high The CLI aliases omit the base_context.

◆ hdrl_bpm_fit_parameter_create_pval()

hdrl_parameter * hdrl_bpm_fit_parameter_create_pval	(	int	degree,
		double	pval
	)

create bpm_fit parameter with p-value bpm treshold

Parameters

degree	degree of fit
pval	p-value of bpm threshold

Returns: hdrl_parameter or NULL on error

See also: hdrl_bpm_fit_compute()

◆ hdrl_bpm_fit_parameter_create_rel_chi()

hdrl_parameter * hdrl_bpm_fit_parameter_create_rel_chi	(	int	degree,
		double	rel_chi_low,
		double	rel_chi_high
	)

create bpm_fit parameter with relative chi bpm treshold

Parameters

degree	degree of fit
rel_chi_low	relative chi distribution bpm lower threshold
rel_chi_high	relative chi distribution bpm upper threshold

Returns: hdrl_parameter or NULL on error

See also: hdrl_bpm_fit_compute()

◆ hdrl_bpm_fit_parameter_create_rel_coef()

hdrl_parameter * hdrl_bpm_fit_parameter_create_rel_coef	(	int	degree,
		double	rel_coef_low,
		double	rel_coef_high
	)

create bpm_fit parameter with relative coefficient bpm treshold

Parameters

degree	degree of fit
rel_coef_low	relative fit coefficient distribution bpm lower threshold
rel_coef_high	relative fit coefficient distribution bpm upper threshold

Returns: hdrl_parameter or NULL on error

See also: hdrl_bpm_fit_compute()

◆ hdrl_bpm_fit_parameter_get_degree()

int hdrl_bpm_fit_parameter_get_degree ( const hdrl_parameter * p )

get degree of polynomial fit of parameter

Parameters

p parameter

Returns: degree of polynomial fit

◆ hdrl_bpm_fit_parameter_get_pval()

double hdrl_bpm_fit_parameter_get_pval ( const hdrl_parameter * p )

get p-value bpm treshold

Parameters

p parameter

Returns: p-value

◆ hdrl_bpm_fit_parameter_get_rel_chi_high()

double hdrl_bpm_fit_parameter_get_rel_chi_high ( const hdrl_parameter * p )

get relative chi distribution upper threshold

Parameters

p parameter

Returns: relative chi distribution upper threshold

◆ hdrl_bpm_fit_parameter_get_rel_chi_low()

double hdrl_bpm_fit_parameter_get_rel_chi_low ( const hdrl_parameter * p )

get relative chi distribution lower threshold

Parameters

p parameter

Returns: relative chi distribution lower threshold

◆ hdrl_bpm_fit_parameter_get_rel_coef_high()

double hdrl_bpm_fit_parameter_get_rel_coef_high ( const hdrl_parameter * p )

get relative fit coefficient distribution upper threshold

Parameters

p parameter

Returns: relative fit coefficient distribution upper threshold

◆ hdrl_bpm_fit_parameter_get_rel_coef_low()

double hdrl_bpm_fit_parameter_get_rel_coef_low ( const hdrl_parameter * p )

get relative fit coefficient distribution lower threshold

Parameters

p parameter

Returns: relative fit coefficient distribution lower threshold

◆ hdrl_bpm_fit_parameter_parse_parlist()

hdrl_parameter * hdrl_bpm_fit_parameter_parse_parlist	(	const cpl_parameterlist *	parlist,
		const char *	prefix
	)

Parse a parameterlist to create input parameters for the BPM_FIT.

Parameters

parlist	parameter list to parse
prefix	prefix of parameter name

Returns: Input parameter for the BPM_FIT computation

Reads a parameterlist in order to create BPM image parameters. Expects a parameterlist containing:

prefix.degree
prefix.pval
prefix.rel-chi-low
prefix.rel-chi-high
prefix.rel-coef-low
prefix.rel-coef-high

◆ hdrl_bpm_fit_parameter_verify()

cpl_error_code hdrl_bpm_fit_parameter_verify ( const hdrl_parameter * p )

verify that the parameter is a valid bpm_fit_parameter

Parameters

p parameter

Returns: error code

Functions

Detailed Description

Function Documentation

◆ hdrl_bpm_fit_compute()

◆ hdrl_bpm_fit_parameter_check()

◆ hdrl_bpm_fit_parameter_create_parlist()

◆ hdrl_bpm_fit_parameter_create_pval()

◆ hdrl_bpm_fit_parameter_create_rel_chi()

◆ hdrl_bpm_fit_parameter_create_rel_coef()

◆ hdrl_bpm_fit_parameter_get_degree()

◆ hdrl_bpm_fit_parameter_get_pval()

◆ hdrl_bpm_fit_parameter_get_rel_chi_high()

◆ hdrl_bpm_fit_parameter_get_rel_chi_low()

◆ hdrl_bpm_fit_parameter_get_rel_coef_high()

◆ hdrl_bpm_fit_parameter_get_rel_coef_low()

◆ hdrl_bpm_fit_parameter_parse_parlist()

◆ hdrl_bpm_fit_parameter_verify()