7 - Computer Vision Flashcards
(11 cards)
What is Computer Vision?
An interdisciplinary scientific field that deals with how computers gain an understanding of the environment from digital images or videos
Where could a Vision System be used?
Used as a Sensor
What is a Digital Image?
A simple grid of numbers where each cell contains info about a single pixel
What is Grayscale
Converting an image to be able to define each pixel as a single scalar value
Allows for:
1. Simple Filters
2. Faster Processing
What is Thresholding (Binary)?
A threshold value is set and each pixel is evaluated
What is Edge Detection?
Identifies a line point in a digital image at which the image brightness changes sharply
Relies on defined thresholds
What is Blob Discover?
Algorithm where subsets of connected components are uniquely labeled based on a given heuristic
- End goal is to ID individual objects within an image
Characteristics of Shape/Facial Recognition
Delauney Triangulation
- Uses triangles or tetrahedra to enclose query points
- Query points can be added or subtracted to tailor level of confidence
What is Optical Flow?
The pattern of apparent motion of objects, surfaces, and edges in a visual scene caused by relative motion between an observer and a scene.
Used for object detection and tracking, robot nav, micro controls
To avoid obstacles, move towards lower optical flow
What is Resolution?
Indicates the level of detail present in an image.
- Dimension
- Total number of pixels (Megapixels)
- Pixels per inch
Effects of Resolution on Computer Vision
Downsampling: Preserves identifying features
Upsampling: Removes sharp gradients making edge detection difficult
