ap csp unit 2

A raw digital sound file samples a sound wave at some interval and measures the height of the wave at each point. Thus, raw sound is recorded as a list of numbers. In very broad terms the MP3 audio compression algorithm identifies frequencies and volume levels - low and high - that are outside the range of human hearing and removes the data representing these frequencies from the original. This technique results in a smaller audio file that sounds exactly the same to the human ear. This technique is an example of what type of compression? a) Lossy compression b) Lossless compression c) Fast Fourier Transform compression d) Tailored compression

a

The colors of the pixels in a digital image are often represented by red, green, and blue values between 0 and 255 (an RGB triplet). A photographer is manipulating a digital image to lighten it because all of the RGB values in the image are less than 100, making it very dark. He does this by adding 20 to the R, G, and B values of each pixel, then overwriting the original image. What type of transformation is the photographer using on the digital image? a) Lossless transformation b) Lossy transformation c) Multiband transformation d) Chrome Sampling transformation e) Compressionless transformation

a

The image shows an encoding for a black and white pixel image. The first two bytes of the data (circled in red) are used to encode the width and height of the image. What is the best term for this type of "data about the data"? a) metadata b) megadata c) superdata d) brontodata e) hexadata

a

What would be the correct binary numbers to make the third color from the left on the bottom row? a) 101 b) 001 c) 111 d) 110

a

Which of the following are equivalent? I. 11110 (base 2) II. 1E (base 16) III. 24 (base 10) a) I and II b) I and III c) II and III d) I, II, and III

a

Which of the following examples best matches the unit of storage: Exabyte a) The entire amount of data transferred over the entire internet b) A very large database such as Facebook photos c) large .iso file (disk image) or harddrive d) .jpeg (image) e) .txt (text)

a

Which of the following is irreversible? a) lossy compression b) lossless compression c) abstraction d) RLI

a

Which of the following statements is FALSE? a) The computer stores colors in hexadecimal b) Every color has 3 components. A red, green and a blue component. c) A bright color would be represented by a large number. d) A computer uses 3 bytes to store a single colored pixel.

a

A problem solving approach (algorithm) to find a satisfactory solution where finding an optimal or exact solution is impractical or impossible a) Lossless Compression b) Heuristic c) Lossy Compression d) Encryption

b

Consider the following three binary numbers: 01010 010000 1110 Which of the following lists the numbers in order from least to greatest? a) 010000 1110 01010 b) 01010 1110 010000 c) 01010 010000 1110 d) 1110 01010 010000

b

The fundamental unit of a digital image, typically a tiny square or dot that contains a single point of color of a larger image a) Image b) Pixel c) Metadata d) Pie Chart

b

There are 240 different values that can be represented by one Green component of a pixel? a) True b) False

b

Which of the file types is an audio file type? a) jpg b) mp3 c) png d) csv

b

Which of the following examples best matches the unit of storage: Petabyte a) The entire amount of data transferred over the entire internet b) A very large database such as Facebook photos c) large .iso file (disk image) or harddrive d) .jpeg (image) e) .txt (text)

b

Which unit is the largest? a) Megabyte b) Terabyte c) Gigabyte d) Kilobyte

b

Which unit is the smallest? a) Megabyte b) Kilobyte c) Gigabyte d) Terabyte

b

A raw digital sound file samples a sound wave at some interval and measures the height of the wave at each point. Thus, raw sound is recorded as a list of numbers. In very broad terms the MP3 audio compression algorithm identifies frequencies and volume levels - low and high - that are outside the range of human hearing and removes the data representing these frequencies from the original. This technique results in a smaller audio file that sounds exactly the same to the human ear. This technique is an example of what type of compression? a) Fast Fourier Transform compression b) Tailored compression c) Lossy compression d) Lossless compression e) Smart compression

c

A video-streaming Web site uses 32-bit integers to count the number of times each video has been played. In anticipation of some videos being played more times than can be represented with 32 bits, the Web site is planning to change to 64-bit integers for the counter. Which of the following best describes the result of using 64-bit integers instead of 32-bit integers? a) 2 times as many values can be represented. b) 32 times as many values can be represented. c) 2^32 times as many values can be represented. d) 32^2 times as many values can be represented.

c

An original file is 100 MB, it is compressed to 80 MB (including dictionary). What is its compression rate? a) 90% b) 80% c) 20% d) 100%

c

Approximately 1,000 ________ are equal to 1 terabyte (1 TB). a) jengabytes b) gigglebytes c) gigabytes d) megabytes e) petabytes

c

The color widget uses 3 bytes of metadata. The first two bytes indicate the width and height of the image. The next byte indicates the number of bits that will be used to represent color. How many bits is used to represent color given the metadata (in binary) 00001000 00001000 0001001 a) 3 bits b) 6 bits c) 9 bits d) 12 bits

c

Under which of the following conditions is it most beneficial to use a heuristic approach to solve a problem? a) When the problem can be solved in a reasonable time and an approximate solution is acceptable b) When the problem can be solved in a reasonable time and an exact solution is needed c) When the problem cannot be solved in a reasonable time and an approximate solution is acceptable d) When the problem cannot be solved in a reasonable time and an exact solution is needed

c

Lil' Nibble, a local Soundcloud rapper, has recorded a new mixtape called "Half-a-byte," produced by "Mibikibi and the Teraflops." The mixtape has several audio files that have been compressed into a .ZIP file so they can be transferred easily and a separate .ZIP file containing album artwork and liner notes. If the mixtape .ZIP file takes up 800 MB and the artwork .ZIP file is 300 MB, what size flash drive do you need in order to transfer the files? a) 512 MB b) 1.0 GB c) 4 KB d) 2.0 GB

d

Which of the following hexadecimal representations would represent dark green? a) #191399 b) #00FF10 c) #001313 d) #001300

d

Which of the following is a reason to use lossy compression? a) You want the compressed file to be larger than the original. b) You want the highest quality audio file possible, with no modifications. c) You want the highest quality image file possible, with no modifications. d) You want to save space and are not concerned if the file is the highest quality possible.

d

Which of the following is a true statement about data compression? a) Data compression is only useful for files being transmitted over the Internet. b) Regardless of the compression technique used, once a data file is compressed, it cannot be restored to its original state. c) Sending a compressed version of a file ensures that the contents of the file cannot be intercepted by an unauthorized user. d) There are trade-offs involved in choosing a compression technique for storing and transmitting data.

d

Which of the following examples best matches the unit of storage: Kilobyte a) The entire amount of data transferred over the entire internet b) A very large database such as Facebook photos c) large .iso file (disk image) or harddrive d) .jpeg (image) e) .txt (text)

e

An artist makes an RGB raster image in which each pixel color is encoded with 12-bits--- 4 bits each for red, green and blue. Which of the following correctly shows the hexadecimal value for Red as a 12-bit representation. a) F00 b) 00F c) FF00 d) FF0000 e) F0F0F0

a

Approximately how much bigger (how many more bytes) is a megabyte than a kilobyte? a) 1,000 times bigger b) 1,000,000 times bigger c) 1,000,000,000 times bigger d) 1,000,000,000,000 times bigger e) 1,000,000,000,000,000 times bigger

a

Approximately how much bigger (how many more bytes) is a megabyte than a kilobyte? a) 1,000 times bigger b) 100,000 times bigger c) 1,000,000 times bigger d) 1,000,000,000 times bigger

a

How would you lighten the color #bcc8e1? a) +50 to each color component b) +50 to the red component c) -50 to each color component d) -50 to the red component

a

A compression scheme for long strings of bits called run-length encoding is described as follows: Rather than record each 0 and 1 individually, instead record runs of bits by storing the number of consecutive 1s and 0s that appear. Since it's binary, any run of 0s must be followed by a run of 1s (even if the run is only 1-bit long) and vice versa. Thus, you can store a list of small numbers that represents the alternating runs of 0s and 1s. Here is an example: To uncompress the data back into its original binary state, you simply reverse the process. This technique is an example of what type of compression? a) Fast Fourier Transform compression b) Lossy compression c) Lossless compression d) Tailored compression e) Hexagonal compression

c

How many bits are needed to represent 8 colors? a) 8 bits b) 24 bits c) 1 hex digit d) 3 bits

d

Select the answer that lists the units of bytes in ascending order (from smallest to largest): a) gigabyte, megabyte, terabyte b) megabyte, terabyte, kilobyte c) gigabyte, terabyte, megabyte d) kilobyte, gigabyte, terabyte

d