by selection of a specific region containing or referencing a pattern; Locating or processing of specific regions to guide the detection or recognition

Full Title

Arrangements for image or video recognition or understanding > Image preprocessing > by selection of a specific region containing or referencing a pattern; Locating or processing of specific regions to guide the detection or recognition

Classification Context

Section:

PHYSICS

Class:

COMPUTING OR CALCULATING; COUNTING

Subclass:

IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING

Scope Notes

Glossary: AR augmented reality ARTag fiducial marker system based on ARToolKit ARToolKit open-source software library for augmented reality FFT fast Fourier transform fiducial marker fiducial markers a fiducial marker is an image element which is explicitly designed for serving as a visual landmark point. A fiducial marker can be as simple as a set of lines forming crosshairs or a rectangle, but it can also be a more elaborate pattern such as an augmented reality tag, which additionally conveys information encoded as a two-dimensional [2D] barcode. Fiducial markers generally provide information about the position and, often, the orientation or the three-dimensional [3D] arrangement of objects in images. Additionally, they can comprise unique identifiers to support the recognition process. Fiducial markers are designed for being easily distinguishable from other image elements; therefore, they commonly have sharp image contrasts (e.g. by limiting their colours to black and white), and they are often designed to generate sharp peaks in the frequency space, allowing them to be easily recognisable by a two-dimensional [2D] Fourier transform. Commonly known fiducial markers are those defined by the augmented reality toolkit (ARToolKit). | Application references: Devices for tracking or guiding surgical instruments Fiducial marks and measuring scales in optical systems Marks applied to semiconductor devices