Image Formats

Question 1

the three most common image file formats

Answer 1

png, jpg and gif

Question 2

image format that is a good balance of quality and compression

Answer 2

jpg

Question 3

compression method used by jpg files

Answer 3

jpeg

Question 4

jpeg acronym

Answer 4

joint photographic experts group

Question 5

approximate number of colors supported by jpg format

Answer 5

16 million - as many as many displays can handle

Question 6

the big difference between jpg and the other two formats

Answer 6

the compression - compressed jps are known as ‘lossy images’

Question 7

what it means for an image to be ‘lossy’

Answer 7

that some of its detail has been lost for the sake of significantly reducing the file size

Question 8

when the gradient in a ‘lossy’ jpg has lines running through it that appear to be multiple pixels high

Answer 8

color banding

Question 9

png acronym

Answer 9

portable network graphics

Question 10

most common color settings for png

Answer 10

16, 256 and 16 million

Question 11

best format if you need to retain detail or need alpha transparency

Answer 11

png

Question 12

difference between single transparency and alpha transparency

Answer 12

single - a color is chosen as the transparent color and each pixel is either transparent or opaque

alpha - each pixel has an alpha channel in addition to red, green and blue

Question 13

gif acronym

Answer 13

graphics interchange format

Question 14

the only format of the 3 that supports animation

Answer 14

gif

Question 15

number of colors a gif can display

Answer 15

gif supports any RGB color, but each gif is limited to a 256 color palette

Question 16

true or false - does gif support transparency?

Answer 16

yes, one of a gif’s 256 colors can be transparent