1D Measuring

List of Operators ↓

This chapter contains operators for 1D measuring.

Concept of 1D measuring

With 1D measuring, edges, i.e., transitions from light to dark or from dark to light, can be located along a predefined line or arc. This allows you to measure the dimension of parts fast and easily with high accuracy. Note that if you want to measure the dimensions of geometric primitives like circles, ellipses, rectangles, or lines, and approximate values for the positions, orientations, and geometric shapes are known, 2D Metrology may be a suitable alternative.

(1) (2)
Measure edges and the distances between them along a line (1) or along an arc (2). These images are from the example programs fuzzy_measure_pin.hdev and measure_ring.hdev.

In the following, the steps that are required to use 1D measuring are described briefly.

Generate measure object:

First, a measure object must be generated that describes the region of interest for the measurement. If the measurement should be performed along a line, the measure object is defined by a rectangle. If it should be performed along an arc, the measure object is defined as an annual arc. The measure objects are generated by the operators

Note that you can use shape-based matching (see chapter Matching / Shape-Based) to automatically align the measure objects.

Perform the measurement:

Then, the actual measurement is performed. For this, typically one of the following operators is used:

Alternatively, if there are extra edges that do not belong to the measurement, fuzzy measuring can be applied. Here, so-called fuzzy rules, which describe the features of good edges, must be defined. Possible features are, e.g., the position, the distance, the gray values, or the amplitude of edges. These functions are created with create_funct_1d_pairscreate_funct_1d_pairsCreateFunct1dPairsCreateFunct1dPairsCreateFunct1dPairs and passed to the tool with set_fuzzy_measureset_fuzzy_measureSetFuzzyMeasureSetFuzzyMeasureSetFuzzyMeasure or set_fuzzy_measure_norm_pairset_fuzzy_measure_norm_pairSetFuzzyMeasureNormPairSetFuzzyMeasureNormPairSetFuzzyMeasureNormPair. Then, based on these rules, one of the following operators will extract the most appropriate edges:

Alternatively to the automatical extraction of edges or points within the measure object, you can also extract a one-dimensional gray value profile perpendicular to the rectangle or annular arc and evaluate this gray value information according to your needs. The gray value profile within the measure object can be extracted with the operator

Destroy measure object handle:

When you no longer need the measure object, you destroy it by passing the handle to

Further operators

In addition to the operators mentioned above, you can use reset_fuzzy_measurereset_fuzzy_measureResetFuzzyMeasureResetFuzzyMeasureResetFuzzyMeasure to discard a fuzzy function of a fuzzy set that was set via set_fuzzy_measureset_fuzzy_measureSetFuzzyMeasureSetFuzzyMeasureSetFuzzyMeasure or set_fuzzy_measure_norm_pairset_fuzzy_measure_norm_pairSetFuzzyMeasureNormPairSetFuzzyMeasureNormPairSetFuzzyMeasureNormPair before, translate_measuretranslate_measureTranslateMeasureTranslateMeasureTranslateMeasure to translate the reference point of the measure object to a specified position, write_measurewrite_measureWriteMeasureWriteMeasureWriteMeasure and read_measureread_measureReadMeasureReadMeasureReadMeasure to write the measure object to file and read it from file again, and serialize_measureserialize_measureSerializeMeasureSerializeMeasureSerializeMeasure and deserialize_measuredeserialize_measureDeserializeMeasureDeserializeMeasureDeserializeMeasure to serialize and deserialize the measure object.


In the following, the most important terms that are used in the context of 1D Measuring are described.

measure object

A data structure that contains a specific region of interest that is prepared for the extraction of straight edges which lie perpendicular to the major axis of a rectangle or an annular arc.

annular arc

A circular arc with an associated width.

Further Information

See also the the “Solution Guide Basics” and “Solution Guide on 1D Measuring” for further details about 1D Measuring.

List of Operators

Delete a measure object.
Deserialize a serialized measure object.
Extract straight edge pairs perpendicular to a rectangle or an annular arc.
Extract straight edge pairs perpendicular to a rectangle or an annular arc.
Extract straight edges perpendicular to a rectangle or an annular arc.
Prepare the extraction of straight edges perpendicular to an annular arc.
Prepare the extraction of straight edges perpendicular to a rectangle.
Extract straight edge pairs perpendicular to a rectangle or annular arc.
Extract straight edges perpendicular to a rectangle or annular arc.
Extract a gray value profile perpendicular to a rectangle or annular arc.
Extracting points with a particular gray value along a rectangle or an annular arc.
Read a measure object from a file.
Reset a fuzzy function.
Serialize a measure object.
Specify a fuzzy function.
Specify a normalized fuzzy function for edge pairs.
Translate a measure object.
Write a measure object to a file.