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Question 1

Explain the difference between analog and digital waveforms

Answer 1

Analog: Continuous and varying.
Digital: Binary

Question 2

Sampling

Answer 2

The process of taking an accurate snapshot of an analog waveform at a particular time

Question 3

Digitization

Answer 3

The process of converting a sample into a binary numeric value

Question 4

What is a sampling rate and how is it typically measured?

Answer 4

The frequency in which snapshots or “samples” are taken. Measured in hertz (Hz).

Question 5

The Nyquist-Shannon sampling theorem tells us that an analog signal can be accurately represented if it is digitally encoded using a sampling rate that is…

Answer 5

Twice greater than the highest frequency being sampled.

Question 6

A traditional audio CD is sampled at how many kHz?

Answer 6

44.1kHz

Question 7

Blu-ray recordings are typically sampled at how many kHz?

Answer 7

48kHz, 96kHz, or 192kHz

Question 8

Bit Depth

Answer 8

The number of bits you have to describe a value.

Question 9

Bit Rate

Answer 9

Measurement of the flow of information over time in a digital signal stream. Measured in bits per second (bps).

Question 10

How do you calculate Bit Rate?

Answer 10

Sample rate x bit depth

Question 11

Compression

Answer 11

Process that allows us to reduce the size of a data stream or file

Question 12

ZIP, FLAC, MPEG-2, PNG, and JPEG2000 are examples of…

Answer 12

Lossless compression

Question 13

MP3, JPEG, HEVC, and H.264 (aka AVC) are examples of

Answer 13

Lossy compression

Question 14

Encoding

Answer 14

The process of analyzing data to reduce its size

Question 15

Decoding

Answer 15

The process of returning compressed data to its original format.

Question 16

A digital media file contains two elements:

Answer 16

Container: Structure of the file where data and metadata are stored
Codec: Provides method of encoding and decoding data

Question 17

Bit

Answer 17

Binary digit. This is the smallest unit of digital information and may have the value 1 or 0.

Question 18

In a digital signal, the on state is represented by ___, and the off state is represented by ___.

Answer 18

1 and 0

Question 19

A signal that has many varying states is called a(n) ______ signal.

Answer 19

Analog

Question 20

Lossy compression is particularly suitable for the transmission of:

A. Spreadsheets
B. Financial data
C. Text files
D. Audio, video, and images

Answer 20

D

Question 21

What is a codec?

Answer 21

A device or processing system that encodes and decodes data.

Question 22

Noise overcomes the signal after many generations of re-amplification of a(n) ______ signal.

Answer 22

Analog