7 - Computer Vision

Question 1

What is Computer Vision?

Answer 1

An interdisciplinary scientific field that deals with how computers gain an understanding of the environment from digital images or videos

Question 2

Where could a Vision System be used?

Answer 2

Used as a Sensor

Question 3

What is a Digital Image?

Answer 3

A simple grid of numbers where each cell contains info about a single pixel

Question 4

What is Grayscale

Answer 4

Converting an image to be able to define each pixel as a single scalar value

Allows for:
1. Simple Filters
2. Faster Processing

Question 5

What is Thresholding (Binary)?

Answer 5

A threshold value is set and each pixel is evaluated

Question 6

What is Edge Detection?

Answer 6

Identifies a line point in a digital image at which the image brightness changes sharply

Relies on defined thresholds

Question 7

What is Blob Discover?

Answer 7

Algorithm where subsets of connected components are uniquely labeled based on a given heuristic
- End goal is to ID individual objects within an image

Question 8

Characteristics of Shape/Facial Recognition

Answer 8

Delauney Triangulation
- Uses triangles or tetrahedra to enclose query points
- Query points can be added or subtracted to tailor level of confidence

Question 9

What is Optical Flow?

Answer 9

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

Question 10

What is Resolution?

Answer 10

Indicates the level of detail present in an image.
- Dimension
- Total number of pixels (Megapixels)
- Pixels per inch

Question 11

Effects of Resolution on Computer Vision

Answer 11

Downsampling: Preserves identifying features
Upsampling: Removes sharp gradients making edge detection difficult