Digital Image Characteristics Flashcards
What is a digital image?
A numerical representation of data possessing both spatial (layout) and intensity (color) information.
What are the two main components of a digital image?
Spatial layout and intensity (color).
How is a digital image represented?
As a multidimensional signal with a two-dimensional array of numbers forming rows (x) and columns (y) in a matrix.
Define a matrix in the context of digital imaging.
A two-dimensional array of numbers representing rows (x) and columns (y) that define small square regions called pixels.
How does matrix size affect image quality?
Larger matrix size improves spatial resolution by decreasing pixel size for the same FOV.
Q: How are matrix indices used?
The indices x and y designate the rows and columns, with I(x,y) representing the response at a specific pixel location.
What is a pixel?
The smallest element in a digital image, representing brightness or intensity.
How does pixel size affect resolution?
Smaller pixel size increases pixel density and resolution.
What factors determine pixel color?
Signal intensity, system’s grayscale, and exposure factors.
How does pixel density relate to image quality?
Higher pixel density improves spatial resolution and image detail.
What is a voxel?
The basic unit of a three-dimensional image, representing a volume of tissue.
How is voxel information displayed in a digital image?
- It is converted into numerical values assigned as brightness levels in pixels.
- Higher values indicate brighter shades, while lower values indicate darker shades.
What is bit-depth?
The number of bits per pixel, indicating the number of grayscale shades available
How is the number of gray shades calculated?
Using the formula 2^n, where n is the bit-depth.
Why is bit-depth important?
Greater bit-depth provides more gray shades, improving contrast resolution and anatomical detail.
What is the relationship between bit-depth and processing time?
Higher bit-depth increases processing time but enhances image quality.
