ITM 207 MIDTERM
Study online at https://quizlet.com/_842ypc
1. Data and computers: are multimedia devices, dealing with a vast array of info categories
store, present, and help us modify
- Numbers
Texts
Video/audio
All stored as binary digits (Bits)
2. Data compression: Reduction in the amount of space needed to store a piece of data or the bandwidth to
transmit it
3. Compression ratio: Size of compressed data divided by size of original data
4. lossless: data can be retrieved without any loss of the original information
5. Lossy Compression: some information is lost permanently in the process
6. analog data: A continuous representation of data, analogues to actual info it represents
7. digital data: A discrete representation, breaking the information up into separate elements
8. Binary representation of data: a type of data that is represented or displayed in the binary numeral
system; the only category of data that can be directly understood and executed by a computer; numerically represented
by a combination of zeros and ones
9. Signed-magnitude number representation: The sign represents the ordering, and the digits
represent the magnitude of the number
Let 0 through 49 represent 0 - 49
Let 50 through 99 represent -50 through -1
10. Tens complement representation: formula to compute the representation of a negative number
Negative(I)= 10k - I, where K is the number of digits
Ex. -3 is negative(3), so using two digits, its representation is
Negative(3)- 100-3=97 97
11. ASCII (American Standard Code for Information Interchange): used 7 bits to repre-
sent each character, allowing 128 unique characters
12. Unicode character set: 16 bits per character, supporting 65,536 unique characters
13. Text Compression: The act of reducing the size of a �le.
1/5
, ITM 207 MIDTERM
Study online at https://quizlet.com/_842ypc
14. types of text compressions: Keyword encoding
Run length encoding
Hu man encoding
15. Keyword Encoding: Replacing a frequently used word with a single character
as=%
16. Run Length Encoding: replacing a long series of a repeated character with a count of the repetition
use ag, repeated value, number of repetitions
17. Hu�man encoding: Using a variable-length binary string to represent a character so that frequently used
characters have short codes
18. Representing Audio Information: Some data lost, reasonable sound reproduced (peak is usually
lost)
- Read by low intensity laser
-Receptor converts re ections into binary digits
-Bit strings represent audio signal
19. pits: re ected poorly
20. lands: re ected well
21. Representing images and graphics: Color is expressed as RGB (red, green, blue) value- three
numbers indicating relative contribution of each primary colours
RGB value of (255, 255, 0) maximizes contribution of red and green, and minimizes blue, which results in bright yellow
Colour depth: amount of data used to represent colour
22. Hi color: 16 bit colour depth: 5 bits used for each number in an RGB value with the extra bit sometimes used
to represent transparency
23. TrueColor: A 24-bit color depth: eight bits used for each number in an RGB value
24. pixels: dots of colour that make up a image
25. resolution: number of pixels in image
2/5
Study online at https://quizlet.com/_842ypc
1. Data and computers: are multimedia devices, dealing with a vast array of info categories
store, present, and help us modify
- Numbers
Texts
Video/audio
All stored as binary digits (Bits)
2. Data compression: Reduction in the amount of space needed to store a piece of data or the bandwidth to
transmit it
3. Compression ratio: Size of compressed data divided by size of original data
4. lossless: data can be retrieved without any loss of the original information
5. Lossy Compression: some information is lost permanently in the process
6. analog data: A continuous representation of data, analogues to actual info it represents
7. digital data: A discrete representation, breaking the information up into separate elements
8. Binary representation of data: a type of data that is represented or displayed in the binary numeral
system; the only category of data that can be directly understood and executed by a computer; numerically represented
by a combination of zeros and ones
9. Signed-magnitude number representation: The sign represents the ordering, and the digits
represent the magnitude of the number
Let 0 through 49 represent 0 - 49
Let 50 through 99 represent -50 through -1
10. Tens complement representation: formula to compute the representation of a negative number
Negative(I)= 10k - I, where K is the number of digits
Ex. -3 is negative(3), so using two digits, its representation is
Negative(3)- 100-3=97 97
11. ASCII (American Standard Code for Information Interchange): used 7 bits to repre-
sent each character, allowing 128 unique characters
12. Unicode character set: 16 bits per character, supporting 65,536 unique characters
13. Text Compression: The act of reducing the size of a �le.
1/5
, ITM 207 MIDTERM
Study online at https://quizlet.com/_842ypc
14. types of text compressions: Keyword encoding
Run length encoding
Hu man encoding
15. Keyword Encoding: Replacing a frequently used word with a single character
as=%
16. Run Length Encoding: replacing a long series of a repeated character with a count of the repetition
use ag, repeated value, number of repetitions
17. Hu�man encoding: Using a variable-length binary string to represent a character so that frequently used
characters have short codes
18. Representing Audio Information: Some data lost, reasonable sound reproduced (peak is usually
lost)
- Read by low intensity laser
-Receptor converts re ections into binary digits
-Bit strings represent audio signal
19. pits: re ected poorly
20. lands: re ected well
21. Representing images and graphics: Color is expressed as RGB (red, green, blue) value- three
numbers indicating relative contribution of each primary colours
RGB value of (255, 255, 0) maximizes contribution of red and green, and minimizes blue, which results in bright yellow
Colour depth: amount of data used to represent colour
22. Hi color: 16 bit colour depth: 5 bits used for each number in an RGB value with the extra bit sometimes used
to represent transparency
23. TrueColor: A 24-bit color depth: eight bits used for each number in an RGB value
24. pixels: dots of colour that make up a image
25. resolution: number of pixels in image
2/5
