How Is Sound And Images Presented In Computers

Question 1

How an image is represented by pixels in binary format?

Answer 1

Images on a computer system are made up of thousands of small coloured dots, known as
pixels (short for picture elements). Bitmap images are stored as an array of pixels. A black
and white bitmap image will store a 1 for a black pixel and 0 for a white pixel.

Question 2

Hwo to find the quality of aound?

Answer 2

Sampling analogue sound

Question 3

What is the sample rate

Answer 3

The number of audio captured evry second

Question 4

What is the bit depth

Answer 4

The number of bits available for each clip

Question 5

What is the bit rate

Answer 5

The number of bits used per second of audio

Question 6

In a colour bitmap image the 1’s and 0’s are replaced by what?

Answer 6

A longer number that represents how much red ,green and blue is required in the colour of each pixel

Question 7

What are vector images?

Answer 7

These images do not store the data by pixels,
but are a set of instructions for drawing a geometric shape. The advantages of a vector
image are that they can be scaled without loss of quality (pixilation etc.) and use less storage
space.

Question 8

Why metadata needs to be included in an image file (including height, width,
colour depth)

Answer 8

The term metadata refers to ‘data about data’. Key properties that are needed to display an
image correctly are stored as metadata. Data such as an image’s height, width and colour
depth are typical examples of data stored in the metadata about an image. Without
metadata, a computer system may render an image incorrectly on screen, such as displaying
all pixels in one row.

Other data may also be stored in the metadata of an image file, such as the date the image
was made, the geographical location of a photograph.