Features
In machine vision, features are referred to as the "objects of interest in the image," and vision inspections are designed around the types of features found in the image.
Types of features in the Inspect Part step include:
Edges
Areas of transition between light and dark pixels; in the horizontal or vertical directions, or circular or arced. Edges can be things like the ends of parts, pins on a circuit board, threads on a screw, the bottoms of bottles or the coil of a spring. These types of features are generally the fastest and easiest to detect.
Circles, Lines and Points
Standard geometric references, which can be utilized to compute measurements.
Patterns
A pattern can be anything from a simple group of repeating shapes to complex configurations like logos or labels. The most reliable type of feature, patterns allow for the greatest range of positional rotation, movement and scale variations, but generally require the most amount of time to inspect.
Blobs
A group of dark or light-colored connected pixels, such as a splotch of white paint on a black background or a black screw on a white conveyor belt. Also one of the faster features to find and allows for variations of the blob feature’s shape and size, but has limited angular orientation value.
Text
Alphanumeric text strings.
Codes
1D barcodes and 2D matrix codes and symbols containing alphanumeric data strings.
Bead
A bead is a continuous, but not necessarily closed-off, pair of edges that define the boundary between two regions of different pixel values, with a width value defining them. For example, a path of welded metal, a path of adhesive or a path of sealant are referred to as "bead" paths.
