Paper 1 - Characters and Storing images

What is alphanumeric

contain both letters, numbers and symbols

define character set

collections of characters that a computer recognises from their binary representation

how many different characters can be represented in ASCII

128

Each ASCII character is given a … binary code

7-bit

what is a benefit of unicode

it covers all major languages

how many characters can extended ascii store

256

The first 128 code in Unicode are … ASCII

the same as

what is the formula for working out the size of a text file (in bits)

number of bits per character x number of characters

what is the colour depth

the number of bits used for each pixel

what is metadata

extra data stored in a file which gives information about the files properties

what may metadata include for an image

file format

height

width

colour depth

resolution

what is the image resolution

the number of pixels in the image