Unit 1- Digital Information

Intellectual property

a work or invention that is the result of creativity, such as a manuscript or a design, to which one has rights and for which one may apply for a patent, copyright, trademark, etc.

Image

A type of data used for graphics or pictures.

Binary

A way of representing information using only two options.

A programmer is creating an app that will convert a binary number to its decimal equivalent. The app will prompt the user to input a binary value, click the convert button, and then display thedecimal equivalent. The programmer is testing the app to ensure it is converting correctly. If the user inputs 10011, what is the correct output in decimal format?

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Warehouse XYZ currently uses 4-bit binary sequences to identify 15 different inventory items it stores. The warehouse is planning to expand by purchasing a local warehouse which will enable them to store an additional 17 inventory items. What's the minimum additional bits the binary sequence will need to uniquely identify each item stored in both warehouses after the expansion?

1 additional bit

The measurement of the length of an object needs to be stored digitally. Assume that 8-bit ASCII encoding is being used. What is the minimum number of bits necessary to represent both the length (an integer number from 0-20) and its unit of measure (represented by two ASCII characters such as "FT" or "IN")?

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Lossy Compression

(or irreversible compression) a data compression method that uses inexact approximations, discarding some data to represent the content. Most commonly seen in image formats like .jpg.

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?

232 times as many values can be represented.

What is the largest number that can be stored using 8 bits of memory?

255

A student needs to represent 26 different letters using binary. What is the minimum number of binary digits she will need to represent this many letters?

5

Hexademical

A base-16 number system that uses sixteen distinct symbols 0-9 and A-F to represent numbers from 0 to 15.

ASCII

American Standard Code for Information Interchange; the universally recognized raw text format that any computer can understand.

Which of the following would result in a better digital approximation of an analog black and white image?

Decreasing the size of each sample square, thus increasing the number of samples taken.

Overflow Error

Error from attempting to represent a number that is too large.

Round- off Error

Error from attempting to represent a number that is too precise. The value is rounded.

How is a Creative Commons license different from a regular copyright?

It allows your work to be shared, reused, and remixed to help spark more creativity.

Bit

a contraction of "Binary Digit"; the single unit of information in a computer, typically represented as a 0 or 1.

Which statement about analog and digital images is true?

Sampling an analog image more frequently produces a digital image with a better representation.

Pixel

Short for "picture element" it is the fundamental unit of a digital image, typically a tiny square or dot which contains a single point of color of a larger image.

Two schools are merging and to adapt to the increased size of the student body, the school is changing its system for keeping track of all student IDs from a system that uses 4-bit binary numbers to one that uses 8-bit binary numbers (AKA 1 byte). Which of the following best describes what effect this change will have?

The 8-bit system will be able to represent sixteen times as many values as the 4-bit system.

Assume your friend just sent you 32 bits of pixel data (just the 0s and 1s for black and white pixels) that were encoded after sampling an image. Choose the two statements that are true.

The correct width and height must be input into the pixelation widget to produce the image. and The fact that only 32 bits were used to represent the image indicates relatively large sample squares were used. The digital image may vary from the analog image significantly.

What is the most important quality of lossless compression?

The data is transformed to usually make it smaller. It can always be re-constructed back to the original.

Encoding protocols determine what type of data can be represented by these values. Which of the following could this byte represent: 0101 1001? Select TWO answers.

The decimal number 89 & A capital letter from the ASCII character set

Which of the following can be represented by exactly two binary digits? Select TWO answers

The first letter of someone?s last name & A person's height

Lossless Compression

a data compression algorithm that allows the original data to be perfectly reconstructed from the compressed data.

Abstraction

a simplified representation of something more complex. Abstractions allow you to hide details to help you manage complexity, focus on relevant concepts, and reason about problems at a higher level.

Recall when you built your information sending device. Why did we decide to send a message as a sequence of two options rather than modifying our devices to represent more options? For example: Modifications with two options bend straw forward once bend straw backwards once bend straw forwards twice bend straw backwards twice vs. Four options bend straw forward bend straw backwards bend straw to the left bend straw to the right

We modified it because it was easier to remember, along with the fact that it took less steps. The options work when you have less messages to send, but when you have 8 it is harder to remember all the different options instead of just remembering a couple modified ones.

Creative Commons

a collection of public copyright licenses that enable the free distribution of an otherwise copyrighted work, used when an author wants to give people the right to share, use, and build upon a work that they have created.

Metadata

data about data. For example, a digital image may include metadata that describe the size of the image, number of colors, or resolution.

Digital Data

data that changes discreetly through a finite set of possible values.

Analog Data

data with values that change continuously, or smoothly, over time.

RGB

the RGB color model uses varying intensities of (R)ed, (G)reen, and (B)lue light are added together in to reproduce a broad array of colors.

Sampling

the process of taking samples from the analog image at regular intervals.

Byte

the standard fundamental unit (or "chunk size") underlying most computing systems today.

Information

what is conveyed or represented by a particular arrangement or sequence of things.