Data Formats

Question 1

Since data within computers are limited to binary numbers, the data (pictures, words, sounds) we input must be converted to what?

Answer 1

Other data forms that are computer-usable so that it can turn the data into 1s and 0s eventually

Question 2

When data input is converted, what happens to it?

Answer 2

Its compressed in some way

Question 3

Lossy vs lossless compression

Answer 3

Lossy means some of the original data is lost, lossless means useless metadata is removed and original data is preserved

Question 4

What is the compression ratio?

Answer 4

The amount file size is reduced

Question 5

What is metadata?

Answer 5

Data that describes or interprets the meaning of data

Question 6

What is digital data?

Answer 6

Easy data like keyboard data that isn’t variable and changing, finite

Question 7

What is analog data?

Answer 7

Data that is continuously changing with time, like data from a camera or microphone.

Question 8

When analog data is input, the data representations the computer converts it to changes it from analog to what?

Answer 8

Digital data

Question 8

What are data representations?

Answer 8

Representations for different types of data that reflect and simplify the ways in which the data is to be processed and will encompass the widest possible user community.

Question 9

Why do we need data representations?

Answer 9

So that various data can be converted into forms recognized by a wide variety of hardware and software so that they can be used by users working within different computer environments.

Question 10

What are some types of data?

Answer 10

Alphanumeric, image (bitmap), image (object), sound, video

Question 11

What is alphanumeric data?

Answer 11

Data entered as characters, symbols, number digits, and punctuations

Question 12

What are the common alphanumeric codes/ data representations?

Answer 12

Unicode, ASCII, and EBCDIC

Question 13

What are the two types of images used within the computer?

Answer 13

Bitmap images and object images

Question 14

Bitmap images and its bitmap representation formats?

Answer 14

Photographs and paintings where every individual point (pixel) needs to be maintained. GIF, PNG, and JPEG

Question 15

Object images and its object representation formats?

Answer 15

Graphical shapes such as lines and curves. Sufficient to store geometrical information and the position of each object. PostScript, TrueType

Question 16

Bitmap image representations are formatted with what?

Answer 16

They’re split into rows and columns with each point called a pixel.

Question 17

Pixel data layout for a bitmap image is called what

Answer 17

A raster

Question 18

The presentation of pixels as input or output, one pixel at a time is called

Answer 18

A raster scan

Question 19

The code for each pixel is translated into actual color values using a color translation table called

Answer 19

A palette, which is stored as part of the image metadata

Question 20

The accuracy of the image representation depends on what?

Answer 20

The size and number of the pixels, aka the resolution

Question 21

Reducing pixel size improves what?

Answer 21

The resolution

Question 22

GIF format:

Answer 22

Complex and can be limiting due to the compatibility of only 256 colors, lossy. Line drawings and simple images

Question 23

PNG format:

Answer 23

Best-known alternative to GIFs, can store up to 48 bits of color per pixel, transparency. Stores only a single image in a file unlike GIFs, lossless. Line drawings and simple images

Question 24

JPEG format:

Answer 24

Lossy compression, reduces image resolution making it good for highly detailed images

Question 25

If a bitmap is shrunk and then enlarged, what happens to its detail?

Answer 25

Permanently lost

Question 26

Pros of object images:

Answer 26

Require far less storage space, manipulated without losing identity

Question 27

Postscript page description language:

Answer 27

A format used to store, transmit, display, and print object images. The page description is a list of procedures and statements that describe each of the objects on a page. This language is stored in ASCII or unicode text form, and the interpreter produces the image.

Question 28

XML, HTML, MathML, PDF and Postscript are examples of what?

Answer 28

Page description languages

Question 29

What is the most important feature in postscript?

Answer 29

The inclusion of scalable font support for the display of text

Question 30

Font outline objects are specified in what way?

Answer 30

In the same way as other objects

Question 31

Can object images be printed directly?

Answer 31

No, they must be converted to bitmap, as most output devices are

Question 32

What are some of the considerations for the storage, transmission, and display of video?

Answer 32

The massive amount of data created

Question 33

How to solve the huge amounts of data in videos?

Answer 33

Compress (biggest thing), reduce image size, limit colors, reduce fps

Question 34

Video format is determined by what?

Answer 34

An encoder/decoder algorithm called a codec.

Question 35

What are a few of these codec standards/formats?

Answer 35

MPEG-2, MPEG-4, H.264, they store and transmit real time video with the video data compressed which is critical for streaming video

Question 36

The codec is embedded in a container/format called what?

Answer 36

MP4

Question 37

Sound has to be converted to digital form for use in a computer using what?

Answer 37

A circuit called an A-to-D converter

Question 38

What is the digital form of sound?

Answer 38

Analog waveform

Question 39

Is it necessary to maintain and store metadata for sound?

Answer 39

Yes

Question 40

MIDI format:

Answer 40

Musical instrument digital interface, contains instructions to recreate or synthesize sounds between connected musical instruments, like keyboards.

Question 41

Other sound formats?

Answer 41

MOD format, VOC format, WAV format, MP3, and AAC