Digital Images

Question 1

What is a pixel?

Answer 1

individual grid or picture element

Question 2

What is the screen resolution?

Answer 2

number of pixels going in a specific direction (left-right, top-bottom)

Question 3

What is aspect ratio?

Answer 3

ratio of the width of the screen compared to height

Question 4

What is color depth?

Answer 4

how many colors can be displayed on a screen

Question 5

What is the bitmap (raster) representation in storing images? What are the advantages?

Answer 5

• image represented by all individual pixels and color of those individual pixels
• can represent a broader variety of images over object approach

Question 6

What is the object(vector) representation in storing images? What are advantages?

Answer 6

• image composed by a number of different geometric shapes, thinking of an image composed by lines, ovals, rectangles, etc.
• takes less space, better quality and manipulation of image

Question 7

What is the difference between lossy and lossless?

Answer 7

With lossless, every bit of data returns after being compressed but lossy loses some of the data after compressing

Question 8

Is bitmap representation lossy or lossless?

Answer 8

Depending on format,
For example, JPEG can be lossy while PNG and GIF are lossless