Normalisation parameters
cutana.normalisation_parameters
¶
Normalisation parameters for Cutana astronomical image processing.
This module defines all default values, ranges, and validation constants for image normalization/stretching methods. These parameters can be easily updated by users to customize the normalization behavior.
The parameters are organized by normalization method and include: - Default values for each parameter - Valid ranges (min/max values) - Step sizes for UI controls - Method-specific defaults for unified parameters
NormalisationDefaults
¶
Default values for normalization parameters.
NormalisationRanges
¶
Valid ranges for normalization parameters.
NormalisationSteps
¶
Step sizes for UI controls.
get_method_specific_a_default(method)
¶
Get the default 'a' parameter value for a specific normalization method.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
method
|
str
|
Normalization method ('asinh', 'log', 'linear', 'zscale') |
required |
Returns:
| Type | Description |
|---|---|
float
|
Default 'a' parameter value for the method |
get_method_specific_a_range(method)
¶
Get the valid range for 'a' parameter for a specific normalization method.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
method
|
str
|
Normalization method ('asinh', 'log', 'linear', 'zscale') |
required |
Returns:
| Type | Description |
|---|---|
Tuple[float, float]
|
Tuple of (min_value, max_value) for the method |
get_method_specific_a_step(method)
¶
Get the step size for 'a' parameter for a specific normalization method.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
method
|
str
|
Normalization method ('asinh', 'log', 'linear', 'zscale') |
required |
Returns:
| Type | Description |
|---|---|
float
|
Step size for the method |
get_default_normalisation_config()
¶
Get default normalization configuration as DotMap.
Returns:
| Type | Description |
|---|---|
DotMap
|
DotMap with default normalization parameters |
get_method_tooltip(method)
¶
Get tooltip text for 'a' parameter based on normalization method.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
method
|
str
|
Normalization method |
required |
Returns:
| Type | Description |
|---|---|
str
|
Tooltip text string |
build_fitsbolt_params_from_external_cfg(external_cfg, num_channels)
¶
Build fitsbolt parameters dictionary from an external fitsbolt configuration.
This function handles the external_fitsbolt_cfg DotMap from AnomalyMatch, converting it to the format expected by fitsbolt.normalise_images().
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
external_cfg
|
DotMap
|
External fitsbolt config DotMap (from AnomalyMatch's fb_create_cfg()) |
required |
num_channels
|
int
|
Number of channels in the images to be normalized |
required |
Returns:
| Type | Description |
|---|---|
Dict[str, Any]
|
Dictionary of fitsbolt parameters ready for normalise_images() |
preserves_physical_scale(config)
¶
Whether normalisation leaves the pixel values on their physical scale.
Only fitsbolt's CONVERSION_ONLY can preserve the scale, and even then only
when the dtype conversion is a no-op: _conversiononly_normalisation returns
the array untouched when the input dtype already matches output_dtype and
is floating, but min-max rescales into the integer range otherwise. Every other
method stretches the pixels by construction.
external_fitsbolt_cfg takes precedence over normalisation_method in
apply_normalisation, so the effective method is read with the same
precedence here — otherwise the header would describe a normalisation that
never ran.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
config
|
DotMap
|
Processing configuration. |
required |
Returns:
| Type | Description |
|---|---|
bool
|
True if the pixel values keep their physical scale through normalisation. |
Raises:
| Type | Description |
|---|---|
AttributeError
|
If a required configuration key is missing (DotMap attribute access on a non-dynamic config). |
convert_cfg_to_fitsbolt_cfg(config, num_channels=1)
¶
Convert Cutana configuration to fitsbolt parameters dictionary.
This function consolidates all the parameter extraction logic from the config and builds the fitsbolt_params dictionary based on the normalisation method. The images array should be added separately to avoid unnecessary data copying.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
config
|
DotMap
|
Configuration DotMap containing all normalisation parameters |
required |
num_channels
|
int
|
Number of channels in the image array (for asinh parameters) |
1
|
Returns:
| Type | Description |
|---|---|
Dict[str, Any]
|
Dictionary containing fitsbolt parameters ready for normalise_images() |
Dict[str, Any]
|
(Note: 'images' key should be added separately by the caller) |