Information Representation Flashcards
(34 cards)
What is a left shift operation in binary representation?
A left shift operation moves all the bits in a binary number to the left by a specified number of positions.
Empty spaces on the right are filled with 0s.
It effectively multiplies the binary number by 2^π where π is the number of positions shifted.
What is a right shift operation in binary representation?
A right shift operation moves all the bits in a binary number to the right by a specified number of positions.
Empty spaces on the left are filled with 0s.
It effectively divides the binary number by 2^π where π is the number of positions shifted.
What is the 1βs complement of a binary number?
The 1βs complement of a binary number is obtained by flipping all its bits (changing 1 to
0 and 0 to 1). It is used to represent negative numbers in binary.
What is the 2βs complement of a binary number?
The 2βs complement of a binary number is obtained by adding 1 to its 1βs complement.
It is widely used to represent negative numbers in computer systems because it simplifies arithmetic operations.
- Invert bits
- Add 1 to the byte
Binary Coded Decimal
Number system that uses 4 bits to represent each denary digit
What is meant by the terms packed and unpacked?
Packed: When each digit is represented by a nibble.
Unpacked: When each digit is represented by a byte.
What are some uses of BCD?
Digital Clocks and Timers:
Commonly used in devices like digital clocks, where decimal numbers are directly displayed.
Calculators:
BCD simplifies the processing and display of decimal numbers in calculators.
When denary digits are to be displayed on digital screen.
When fixed point denary numbers are to be displayed, for example: 300.25
Character Set
If text is to be stored in a computer system, each character needs to be assigned a binary value for it to be understood by a computer. A character set is a defined collection of characters that a computer can recognize, store, and process. It includes letters, digits, symbols, and control characters, with each assigned a unique numerical code.
ASCII Code
The ASCII (American Standard Code for Information Interchange) code is a 7-bit character set used to represent English letters, digits, and control characters. It supports 128 characters, including uppercase and lowercase letters, numbers, and symbols.
Extended ASCII
Extended ASCII is an 8-bit extension of the ASCII code, allowing for 256 characters. It includes the standard ASCII characters plus additional symbols, graphical characters, and foreign language letters for broader usage.
Unicode
Unicode is a universal character set designed to support every character in every language. Whether its emojis, letters, numbers etc, itβs an all-in-one solution. It uses different encoding formats, like UTF-8 and UTF-16, and can represent over a million characters, ensuring global compatibility.
What are the two types of images?
Bitmap and Vector
Define Bitmap images.
- They are stored as a series of tiny dots called pixels.
- Each pixel is assigned a value and a color.
- When zooming in (enlarging a bitmap image - pixelated), it appears as a poor quality image because pixels are stretched out.
Screen resolution
It shows how many pixels your screen can display horizontally and vertically.
Image resolution
It is a measurement of pixel per inch in an image. It is the total number of pixels in an image.
Color depth
It is the number of bits stored in each pixel.
2^π = Number of colors stored in an image. Here n is the color depth.
Image file size
Total Number of Pixels x Colour Depth of Pixels
File Header
It confirms file as a bitmap (BMP). It tells you about a fileβs size, the location of image data, the image resolution, color depth and type of file compression technique if any used. Itβs examples include BMP, JPEG, AVI, PCX etc.
What is a Vector Graphic?
It is the use of mathematical formulaes to draw lines and curves to form an image. It is made from geometric objects, and uses SVG (scalable vector graphics) format. The more the image is zoomed in, more clearer it gets.
What is a drawing list?
It is a set of commands used to define a vector image.
What are drawing properties?
It is the basic geometric data such as a circle, the position of its centre, the thickness, color, style of shapes etc.
What is a drawing object?
It is a mathematically/geometrically defined construct such as a rectangle, line, circle etc.
Compare bitmap and vector images.
- Vector image scales without file size increase unlike bitmap images.
- Vector image scales without distortion unlike bitmap images.
Sound
It is an analogue value which needs to be digitized in order to store and represent sound in a computer.
