Technology-Chapter 8

Question 1

Pixels

Answer 1

from picture elements, are small points of colored light arranged in a grid to form a computer display

Question 2

RGB-always in that order

Answer 2

Each pixel is formed from three colors lights: red, green, blue

Question 3

white and black result from,,,

Answer 3

white- high intensity

black-turning off all of them

Question 4

Intensities

Answer 4

All colors are made by using different amounts of intensities by all three lights.

Question 5

Pixels , the light shines directly at our eyes which means

Answer 5

nothing is absorbed nor reflected

Question 6

Thin Film TransiStor (TFT)

Answer 6

A form of liquid crystal display (LCD), known also as active matrix, these are the standard “flat” or “thin” displays used for laptops, phones, and so on.

Question 7

Representing the color os a single pixels requires..

Answer 7

3 bytes

Question 8

Brightness refers to

Answer 8

how close to the white the pixels are

Question 9

Contrast

Answer 9

is the side of the difference between the darkest and lightest portions of the image

Question 10

100%

Answer 10

white point

Question 11

0%

Answer 11

black point

Question 12

gamma point

Answer 12

midpoint

Question 13

The force , or intensity of the push, determines the volume, and the frequency ( the number of waves per second) of the pushes is the ..

Answer 13

pitch

Question 14

analog

Answer 14

the key from a digitization point of view is that the object vibrates continuously, producing a continuously changing wave.

convert data to bits

Question 15

Thomas edison

Answer 15

analog rep.

scratch on a wax cylinder

Question 16

Sample

Answer 16

to take measurements at regular intervals

Question 17

sampling rate

Answer 17

the number of samples in a second

Question 18

Nyquist rule

Answer 18

a sampling rate must be at least twice as fast as the fastest frequency

Question 19

humans can hear

Answer 19

20,000 hz

Question 20

transduscer

Answer 20

converts a sound wave into an electrical wave

Question 21

analog-to-digtal converter (ADC)

digitizing process

Answer 21

an electrical signal is fed into this, which takes the continuos wave and smokes it at regular intervals, outputting for each sample binary numbers

Question 22

Digital-to-analog converter (DAC)

reversed to play sound

Answer 22

The numbers are read from memory into the decompressor which produces binary numbers, they are inputed into this and creates an electrical wave by interpolation between the digital values- that is, filling in or smoothly moving from one value to another.

Question 23

Bits must represent

Answer 23

positive and negative values

the more bits, the more accurate the measurements

Question 24

audio number of bits

Answer 24

16

Question 25

advantages of digital sound

Answer 25

fix and compress it, reproduce exactly

Question 26

compression ratio

Answer 26

number of bits is reduced to about one-tenth of what it was

Question 27

Compression

Answer 27

means to change the representation in order to use fewer bits to store or transmit information

Question 28

Run-length encoding

Answer 28

uses binary numbers to specify how long the first sequence of 0's is , then how long the following sequence of 1's is, then how long the following sequence of 0's is , and so on.

Question 29

Run-length encoding is a lossless compression scheme which means

Answer 29

meaning that the original representation of 0'sand 1's can be perfectly reconstructed from the compressed version. ex: MP3

Question 30

lossy compression

Answer 30

that the original representation cannot be exactly reconstructed from the compressed form.

Question 31

JPEG

Answer 31

invented by the Joint Photographic Experts Group of the ISO. is a lossy compression technique that exploits the same kinds of "human perception" characteristics that MP3 does, only for light and color.

Question 32

luminance

Answer 32

small changes in brightness

Question 33

chrominance

Answer 33

small differences in color

Question 34

MPEG

Answer 34

Motion Picture Experts Group of the ISO, JPEG-type compression is applied to each frame, but then "interframe coherency" is used.

Question 35

Optical Character Recognition

Answer 35

let you search for a word in the picture, pixel must be converted to text by this process

Question 36

features

Answer 36

When a computer scans a group of pixels looking for edges where the color changes, form these into this, parts of a character to be recognized

Question 37

Classifier

Answer 37

uses the features and matches them to an alphabet to determine which one is close

Question 38

Latency

Answer 38

the time it takes for information to be created or delivered-greatly influences our experience with technology

Question 39

absolute limit

Answer 39

the speed of light, lenders the fastness of seeing an image

Question 40

Bandwidth

Answer 40

a measure of how much information is transmitted per unit of time

Question 41

Bias-Free Universal Medium Principle

Answer 41

bits can represent all discrete information; bits have no inherent meaning

Question 42

Interpretation

Answer 42

the meaning of bits comes from us or by the computer through our programs