Quiz Unit 2, Lessons 3, 4, 5 Additional Practice and Notes on what’s on quiz ANSWERS AT END OF DOCUMENT

What’s on quiz: - Black and white images - Color images - Lossy and lossless compression - File types - Heuristic - metadata

Questions are below, answer key at end. NOTE: separate document for Hexadecimal, Binary, decimal conversion practice

NOTE: FOR ALL QUESTIONS ABOUT IMAGE SIZE, ASSUME THAT METADATA IS: - One byte for width - One byte for height - One byte for bits-per-pixel (only for color)

1. How many bytes are required to encode an image that is 40 pixels wide and 40 pixels tall, if you encode each pixel with 3 bytes (24 bits) of RGB data?

2. How many byes would it take to represent a black and white image that is 40 pixels by 40 pixels

3. A digital artist comes up to you and says, “Help! I need a 24-bit color that’s ‘less blue’ than #2233FF.” What would you tell her?

Assume 3 bits per color (or a total of 9 bits) for these questions on RGB:

4. Which color will be a brighter blue? a. 001001111 b. 100111100

5. Which color will be a darker green? a. 001111000 b. 001010001 Match the file type with the definition

Hexidecimal, binary, decimal conversion practice – see separate pdf document. NOTE: PDF contains “0x” as a prefix for every hexadecimal number. That’s just a prefix and should not be included in your conversion. ANSWERS

6. How many bytes are required to encode an image that is 40 pixels wide and 40 pixels tall, if you encode each pixel with 3 bytes (24 bits) of RGB data? a. 40 * 40 = 1600 b. 1600 pixels *3 bytes = 4800 c. Add in 3 bytes of data for metadata d. Total: 4803

7. How many byes would it take to represent a black and white image that is 40 pixels by 40 pixels

a. 40*40 – 1600 b. Add in 3 bytes of data for metadata c. Total: 1603

8. A digital artist comes up to you and says, “Help! I need a 24-bit color that’s ‘less blue’ than #2233FF.” What would you tell her?

a. #2233FE or #2233EE

Assume 3 bits per color (or a total of 9 bits) for these questions on RGB:

9. Which color will be a brighter blue? c. 001001111 **** d. 100111100

10. Which color will be a darker green? c. 001111000 d. 001010001 ****

Answers to match the file type with the definition Hexidecimal, binary, decimal conversion practice – see separate pdf document. NOTE: PDF contains “0x” as a prefix for every hexadecimal number. That’s just a prefix and should not be included in your conversion.