gen_measure_rectangle2 ( : : Row, Column, Phi, Length1, Length2, Width, Height, Interpolation : MeasureHandle )

Prepare the extraction of straight edges perpendicular to a rectangle.

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.

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.

With gen_measure_rectangle2, all computations which can be used for multiple measurements are removed from the actual measurement. To effect this, an optimized data structure, a so-called measure object, is constructed and returned in MeasureHandle. In order to perform the measurement at the optimum speed, the size of the images for which subsequent measurements will be made must already be specified in gen_measure_rectangle2 with the parameters Width and Height. This technique increases the speed of the actual measurement significantly.

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.


Parameters

Row (input_control)
rectangle2.center.y -> real / integer
Row coordinate of the center of the rectangle.
Default value: 50.0
Suggested values: 10.0, 20.0, 50.0, 100.0, 200.0, 300.0, 400.0, 500.0
Typical range of values: 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 value: 100.0
Suggested values: 10.0, 20.0, 50.0, 100.0, 200.0, 300.0, 400.0, 500.0
Typical range of values: 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 value: 0.0
Suggested values: -1.178097, -0.785398, -0.392699, 0.0, 0.392699, 0.785398, 1.178097
Typical range of values: -1.178097 <= Phi <= 1.178097 (lin)
Minimum increment: 0.001
Recommended increment: 0.1
Restriction: (- pi < Phi) && (Phi <= pi)

Length1 (input_control)
rectangle2.hwidth -> real / integer
Half width of the rectangle.
Default value: 200.0
Suggested values: 3.0, 5.0, 10.0, 15.0, 20.0, 50.0, 100.0, 200.0, 300.0, 500.0
Typical range of values: 0.0 <= Length1 <= 511.0 (lin)
Minimum increment: 1.0
Recommended increment: 10.0

Length2 (input_control)
rectangle2.hheight -> real / integer
Half height of the rectangle.
Default value: 100.0
Suggested values: 1.0, 2.0, 3.0, 5.0, 10.0, 15.0, 20.0, 50.0, 100.0, 200.0
Typical range of values: 0.0 <= Length2 <= 511.0 (lin)
Minimum increment: 1.0
Recommended increment: 10.0
Restriction: Length2 <= Length1

Width (input_control)
extent.x -> integer
Width of the image to be processed subsequently.
Default value: 512
Suggested values: 128, 160, 192, 256, 320, 384, 512, 640, 768
Typical range of values: 0 <= Width <= 1024 (lin)
Minimum increment: 1
Recommended increment: 16

Height (input_control)
extent.y -> integer
Height of the image to be processed subsequently.
Default value: 512
Suggested values: 120, 128, 144, 240, 256, 288, 480, 512, 576
Typical range of values: 0 <= Height <= 1024 (lin)
Minimum increment: 1
Recommended increment: 16

Interpolation (input_control)
string -> string
Type of interpolation to be used.
Default value: 'nearest_neighbor'
List of values: 'nearest_neighbor', 'bilinear', 'bicubic'

MeasureHandle (output_control)
measure_id -> integer
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 handling is raised.


Parallelization Information

gen_measure_rectangle2 is reentrant and processed without parallelization.


Possible Predecessors

draw_rectangle2


Possible Successors

measure_pos, measure_pairs, fuzzy_measure_pos, fuzzy_measure_pairs, fuzzy_measure_pairing, measure_thresh


Alternatives

edges_sub_pix


See also

gen_measure_arc


Module

Sub-pixel operators



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