List of Operators ↓
This chapter describes operators for using structured light.
The basic concept behind structured light is the display of known patterns onto a display or projector. The way those patterns appear in the scene after hitting surfaces helps to further analyze the surfaces.
To use structured light, a model must first be created using
. The model type is specified in
. Currently, only the model type
is supported. Deflectometry is the procedure of analyzing the reflections
of known patterns from specular or semi-specular surfaces. In
such a setup, for every pattern image projected on the screen, a camera
image of the reflection is acquired. Deformations of the pattern in the
camera image imply a defect on the specular surface.
In the following, the steps that are required to perform defect detection on specular surfaces are described briefly.
In the first step, a structured light model is created with
or read with
The different structured light model parameters can then be set with
or queried with
. The pattern parameters
'pattern_type' specify along
with the stripe parameters
'single_stripe_width' the specifications of the pattern images to
be generated and projected onto the specular surface. Finally, the
'persistence' parameter can be enabled to debug intermediate
The pattern images are to be generated with
after setting all relevant parameters.
Please ensure that the output images are as needed in the particular setup.
At this stage, the pattern images are shown on the display and reflected by the specular surface. The respective reflected image is acquired by the camera for each pattern image.
can be decoded with
. Upon calling this operator, the
correspondence images are created and stored in the model
Now the decoded
'correspondence_image', as well as other results
can be queried with
'defect_image' can be generated and queried with
. For more details of the different
objects that can be queried, please refer to the operator's documentation.
The structured light model offers various other operators that help access and update the various parameters of the model.
enables writing the
structured light model to a file. Please note that previously generated
pattern images are not written in this file. A structured light model file
can be read using
Furthermore, it is possible to serialize and deserialize the structured
light model using
See also the
“Solution Guide Basics” for further details.