gen_measure_rectangle2🔗
Short description🔗
gen_measure_rectangle2 — Prepare the extraction of straight edges perpendicular to a rectangle.
Signature🔗
gen_measure_rectangle2( rectangle2.center.y Row, rectangle2.center.x Column, rectangle2.angle.rad Phi, rectangle2.hwidth Length1, rectangle2.hheight Length2, extent.x Width, extent.y Height, string Interpolation, out measure MeasureHandle )
Description🔗
gen_measure_rectangle2 prepares the extraction of
straight edges which lie perpendicular to the major
axis of a rectangle. The center of the rectangle is passed in the
parameters Row and Column, the direction of the
major axis of the rectangle in Phi, and the length of the
two axes, i.e., half the diameter of the rectangle, in
Length1 and Length2.
For an explanation of the concept of 1D measuring see the introduction of chapter 1D Measuring.
The edge extraction algorithm is described in the documentation of
the operator measure_pos. As discussed there, different
types of interpolation can be used for the calculation of the
one-dimensional gray value profile. For Interpolation =
'nearest_neighbor', the gray values in the measurement are
obtained from the gray values of the closest pixel, i.e., by
constant interpolation. For Interpolation =
'bilinear', bilinear interpolation is used, while for
Interpolation = 'bicubic', bicubic interpolation
is used.
To perform the actual measurement at optimal speed, all computations that can
be used for multiple measurements are already performed in the operator
gen_measure_rectangle2. For this, an optimized data structure, a
so-called measure object, is constructed and returned in
MeasureHandle. The size of the images in which measurements will be
performed must be specified in the parameters Width and
Height.
The system parameter 'int_zooming' (see set_system)
affects the accuracy and speed of the calculations used to construct
the measure object. If 'int_zooming' is set to
'true', the internal calculations are performed using fixed
point arithmetic, leading to much shorter execution times. However,
the geometric accuracy is slightly lower in this mode. If
'int_zooming' is set to 'false', the internal
calculations are performed using floating point arithmetic, leading
to the maximum geometric accuracy, but also to significantly
increased execution times.
Attention🔗
Note that when using bilinear or bicubic interpolation, not only the measurement rectangle but additionally the margin around the rectangle must fit into the image. The width of the margin (in all four directions) must be at least one pixel for bilinear interpolation and two pixels for bicubic interpolation. For projection lines that do not fulfill this condition, no gray value is computed. Thus, no edge can be extracted at these positions.
Please also note that the center coordinates of the rectangle are rounded internally, so that the center lies on the pixel grid. This is done to ensure consistency.
Execution information🔗
Execution information
-
Multithreading type: reentrant (runs in parallel with non-exclusive operators).
-
Multithreading scope: global (may be called from any thread).
-
Processed without parallelization.
This operator returns a handle. Note that the state of an instance of this handle type may be changed by specific operators even though the handle is used as an input parameter by those operators.
Parameters🔗
Row (input_control) rectangle2.center.y → (real / integer)
Row coordinate of the center of the rectangle.
Default: 300.0
Suggested values: 10.0, 20.0, 50.0, 100.0, 200.0, 300.0, 400.0, 500.0
Value range: 0.0 ≤ Row ≤ 511.0 (lin)
Minimum increment: 1.0
Recommended increment: 10.0
Column (input_control) rectangle2.center.x → (real / integer)
Column coordinate of the center of the rectangle.
Default: 200.0
Suggested values: 10.0, 20.0, 50.0, 100.0, 200.0, 300.0, 400.0, 500.0
Value range: 0.0 ≤ Column ≤ 511.0 (lin)
Minimum increment: 1.0
Recommended increment: 10.0
Phi (input_control) rectangle2.angle.rad → (real / integer)
Angle of longitudinal axis of the rectangle to horizontal (radians).
Default: 0.0
Suggested values: -1.178097, -0.785398, -0.392699, 0.0, 0.392699, 0.785398, 1.178097
Value range: Phi (lin)
Minimum increment: 0.001
Recommended increment: 0.1
Length1 (input_control) rectangle2.hwidth → (real / integer)
Half width of the rectangle.
Default: 100.0
Suggested values: 3.0, 5.0, 10.0, 15.0, 20.0, 50.0, 100.0, 200.0, 300.0, 500.0
Value range: 1.0 ≤ Length1 (lin)
Minimum increment: 1.0
Recommended increment: 10.0
Length2 (input_control) rectangle2.hheight → (real / integer)
Half height of the rectangle.
Default: 20.0
Suggested values: 1.0, 2.0, 3.0, 5.0, 10.0, 15.0, 20.0, 50.0, 100.0, 200.0
Value range: 0.0 ≤ Length2 (lin)
Minimum increment: 1.0
Recommended increment: 10.0
Width (input_control) extent.x → (integer)
Width of the image to be processed subsequently.
Default: 512
Suggested values: 128, 160, 192, 256, 320, 384, 512, 640, 768
Value range: 0 ≤ Width (lin)
Minimum increment: 1
Recommended increment: 16
Height (input_control) extent.y → (integer)
Height of the image to be processed subsequently.
Default: 512
Suggested values: 120, 128, 144, 240, 256, 288, 480, 512, 576
Value range: 0 ≤ Height (lin)
Minimum increment: 1
Recommended increment: 16
Interpolation (input_control) string → (string)
Type of interpolation to be used.
Default: 'nearest_neighbor'
List of values: 'bicubic', 'bilinear', 'nearest_neighbor'
MeasureHandle (output_control) measure → (handle)
Measure object handle.
Result🔗
If the parameter values are correct the operator
gen_measure_rectangle2 returns the value 2 (H_MSG_TRUE).
Otherwise an exception is raised.
Combinations with other operators🔗
Combinations
Possible predecessors
Possible successors
measure_pos, measure_pairs, fuzzy_measure_pos, fuzzy_measure_pairs, fuzzy_measure_pairing, measure_thresh
Alternatives
See also
Module🔗
1D Metrology