smallest_rectangle1🔗
Short description🔗
smallest_rectangle1 — Surrounding rectangle parallel to the coordinate axes.
Signature🔗
smallest_rectangle1( region Regions, out rectangle.origin.y Row1, out rectangle.origin.x Column1, out rectangle.corner.y Row2, out rectangle.corner.x Column2 )
Description🔗
The operator smallest_rectangle1 calculates the surrounding
rectangle of all input regions (parallel to the coordinate axes).
The surrounding rectangle is described by the coordinates of the
corner pixels
(Row1,Column1,Row2,Column2).
The calculation of the rectangle is based on the center coordinates
of the region pixels.
The smallest axis aligned surrounding rectangle of a region. Note that the calculation is based on the center coordinates of the region pixels.
If more than one region is passed in Regions, the results
are stored in tuples, the index of a value in the tuple
corresponding to the index of a region in the input. In case of
empty region all parameters have the value 0 if no other behavior
was set (see set_system).
Attention🔗
In case of empty region the result of
Row1,Column1, Row2 and Column2
(all are 0) can lead to confusion.
Execution information🔗
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🔗
Regions (input_object) region(-array) → object
Regions to be examined.
Row1 (output_control) rectangle.origin.y(-array) → (integer)
Line index of upper left corner point.
Column1 (output_control) rectangle.origin.x(-array) → (integer)
Column index of upper left corner point.
Row2 (output_control) rectangle.corner.y(-array) → (integer)
Line index of lower right corner point.
Column2 (output_control) rectangle.corner.x(-array) → (integer)
Column index of lower right corner point.
Complexity🔗
If \(F\) is the area of the region the mean runtime complexity is \(O(sqrt(F))\).
Result🔗
The operator smallest_rectangle1 returns the value 2 (H_MSG_TRUE) if
the input is not empty. The behavior in case of empty input (no
input regions 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.
Combinations with other operators🔗
Combinations
Possible predecessors
threshold, regiongrowing, connection, runlength_features
Possible successors
disp_rectangle1, gen_rectangle1
Alternatives
height_width_ratio, smallest_rectangle2, area_center
See also
Module🔗
Foundation