Operator Reference
hamming_distance_norm (Operator)
hamming_distance_norm
— Hamming distance between two regions using normalization.
Signature
hamming_distance_norm(Regions1, Regions2 : : Norm : Distance, Similarity)
Description
The operator hamming_distance_norm
returns the hamming distance
between two regions,
i.e., the number of pixels of the regions which are different
(Distance
).
Before calculating the difference the region in
Regions1
is normalized onto
the regions in Regions2
.
The result is the number of pixels contained in one region
but not in the other:
The parameter Similarity
describes the similarity between the
two regions based on the hamming distance Distance
:
The following types of normalization are available:
- 'center' :
The region is moved so that both regions have the save center of gravity.
If both regions are empty Similarity
is set to 0.
The regions with the same index from both input parameters are
always compared.
Attention
In both input parameters the same number of regions must be passed.
Execution Information
- Multithreading type: reentrant (runs in parallel with non-exclusive operators).
- Multithreading scope: global (may be called from any thread).
- Automatically parallelized on tuple level.
Parameters
Regions1
(input_object) region(-array) →
object
Regions to be examined.
Regions2
(input_object) region(-array) →
object
Comparative regions.
Norm
(input_control) string(-array) →
(string)
Type of normalization.
Default: 'center'
List of values: 'center'
Distance
(output_control) integer(-array) →
(integer)
Hamming distance of two regions.
Assertion:
Distance >= 0
Similarity
(output_control) real(-array) →
(real)
Similarity of two regions.
Assertion:
0 <= Similarity && Similarity <= 1
Complexity
If F is the area of a region the mean runtime complexity is O(sqrt(F)).
Result
hamming_distance_norm returns the value 2 (
H_MSG_TRUE)
if the number of objects in
both parameters is the same and is not 0.
The behavior in case of empty input (no input objects available) is
set via the operator set_system('no_object_result',<Result>)
.
The behavior in case of empty region (the region is the empty set) is set via
set_system('empty_region_result',<Result>)
.
If necessary an exception is raised.
Possible Predecessors
threshold
,
regiongrowing
,
connection
Alternatives
intersection
,
complement
,
area_center
See also
Module
Foundation