Data Representation Flashcards
(18 cards)
What is Resolution?
How many pixels are in a certain space
What is Colour Depth?
The number of bits used for each pixel
What is Metadata?
The information about the image file that is stored within it
What is Sampling?
The amplitude of the wave is measured at regular intervals which creates a digital representation of the wave
What is Compression?
Makes the files sizes smaller
What is Lossy Compression?
Permanently removes some of the data from a file to make the file size smaller
What is Lossless Compression?
Data is temporarily removed from the file and then put back together when it is opened
What are Images made up of?
Pixels
What numbers does Denary use?
0-9
What numbers does Binary use?
0 and 1
What values does Hexadecimal use?
0 - F
How many Bits are in a Byte?
8 Bits
What is a Binary Shift?
Moving the Binary Number to the Left or Right
Left Shift - Multiplies the number by 2
Right Shift - Divides the number by 2
What is a Character Set?
The characters that are recognised or represented by a computer system
What is ASCII?
Each character is represented by a 7 bit number with a 0 in front to make it up to a byte
What is Extended ASCII?
Each character is represented by an 8 bit binary number
How many different possibilities are there in Extended ASCII?
256 Possibilities
What is Unicode?
Each letter is represented by a 16 bit or 32 bit binary number
This gives at least twice as many character options as ASCII and allows the character set to represent characters and symbols from all languages