Chapter 4 Test

binary numbering system

how is memory stored in the computer?

base 2 positional

what kind of numbering system is binary base

signed magnitude notation

number representation in which the sign represents the ordering of the number (negative and positive) and the value represents the magnitude

1

what is the number to show negative in sign/magnitude notation

0

what is the number to show positive in sign/magnitude notation

16 (65,536)

how many bits does Unicode use

ASCII

Unicode is a superset of what

32 (4 billion)

Unicode has a variant of what bit

ASCII

American Standard Code for Information Interchange

8 (256)

what bit is ASCII

010 and 011

uppercase and lowercase in ASCII

65-90 and 97-122

uppercase alphabet and lowercase alphabet in ASCII

Analog Representation

Objects can take on any continuous value

a tone in sound

an example of analog representation

amplitude

what measures the loudness (height) of a waveform

period

what measures the time it takes for the waveform to complete a cycle

frequency (hertz)

what measures the total number of cycles per unit time of a waveform

pitch

what does frequency measure

f = 1/T

what is hertz defined as

20,000

hertz a human ear can detect

sampling rate

how many times per second we sample the amplitude of the sound wave

a more accurate reproduction

a greater sampling rate results in what

bit depth

the number of bits used to encode each sample

16 (65,000) or 24 (16,000,000)

most audio encoding schemes use how many bits

pixels

points of color

a more accurate encoding of an image

more pixels results in what

bitmap

rectangular grid of pixels

number of bits

each pixels color is specified by what

color depth

bits per pixel

raster graphics

A dot matrix data structure that represents a generally rectangular grid of pixels, stored in image files with varying formats

JPEG

Raster, lossy compression

PDF

Vector, Lossless

GIF

This extension is Lossless compression

computer driven and lossless compression

Vectors are what and what

PNG

Raster, Lossless improvement to GIF

Vector

SVG and EPS

compression ratio

how much compression schemes reduce the storage requirements of the data

Significant saving of space

if the commonly used characters are less bits, what happens

uncompressed data/compressed data

how do you calculate compression ratio

Lossless Compression

No information is lost in the compression and its possible to exactly reproduce that original data.

Lossy Compression

Data is compressed in a way that does not fully guarantee all of the information in the original data can be fully and completely recreated

MP3

Lossy Compression

What does Lossy compression allow for

Allows for higher compression ratios as they give up small inaccuracies undetectable by the human eye.

pitch

highness or lowness of a sound

digitized

digital signals are created from sampling an analog signal

numerical amplitudes

A wave is represented in a computer as a sequence of what

sequential circuit

contain feedback loops in which the output of a gate is fed back as input to an earlier gate

Memory units

Sequential circuits are used to build what

transistor

An electronic device that can be in an OFF state, which does not allow electricity to flow, or in an ON state, in which electricity can pass unimpeded; a transistor is a solid-state device that has not mechanical or moving parts

ON

a closed switch is what for the transistor

OFF

an open switch is what for the transistor

semiconductors

what are transistors made of

Multiplexer

multiple inputs become one output (signal)

Demultiplexer

One input (signal) is split into multiple outputs

trapezoid

what shape is used for multiplexer and demultiplexer

transistor

elementary building block for all modern computer systems

magnetic core

what came before the transistor

vector graphics

computer graphics images that are defined in terms of 2D points, which are connected by lines and curves to form polygons and other shapes