COMP6021 Class 06.3

We looked at lossy compression, interpolation, and indexed colour.

COMP6021 Class 06.2

We looked at the RGB, Lab, and CMYK colour systems. I also mentioned Pantone

See also Capsure

This video may be of use

COMP6021 Class 06.1 Digital Colour

We began our look at colour and how it is represented.

Thine video may be of use

COMP6021 Class 05.4

We used Photoshop to experiment with different resolutions and pixel depths. I asked students to download a large image and to do some messing about of their own

COMP6021 Class 05.3

We looked at digitisation.

We considered quantisation of temperature and then temperature over time. We looked at how B&W images are digitized.

This video may also be of use

COMP6021 Class 05.2

I gave students two exam questions from past papers on LZW. Student worked on them alone, and then we worked out the answers on the board.

COMP6021 Class 05.1 LZW

We looked at the Lempel-Ziv-Welch algorithm for encoding text

COMP6021 Class 04.4 - tutorial

Students had very few questions so once we were done we left early

COMP6021 Class 04.3

We did two examples of Huffman coding with 8 symbols.

COMP6021 Class 04.2

I planned to do exercises on generating UTF-8 and on Huffman coding. However the UTF-8 proved tricker than we expected, so we will do the Huffman in the next class.

We converted the following to UTF-8, but it took us a while to figure out how do deal with padding zeros.


1F498 
11110000:10011111:10010010:10011000 
f09f9298




1F46B 
11110000:10011111:10010001:10101011 
f09f91ab





1F600
11110000:10011111:10011000:10000000 
 f09f9880

COMP6021 Class 04.1

[No recording of today's class. Sound too bad]

We played Hangman to illustrate the point that letters in English do not occur with the same frequencies.  We looked at how compression can be used to represent information using fewer bits.

We looked at Huffman's algorithm for devising optimal variable length codes.

To be honest, the video I made below says it better than I did in class anyway. (I hope my best work isn't behind me!)

Video on Variable Length Codes

I gave students an exercise to complete in time for the next class.

COMP6021 Class 03.4 & 03.4

We attempted to do an experiment to see how many bytes are required to store a Japanese character in UTF-8 but could paste Japanese into any of the text editors. 

Students did an exam question on decoding UTF-8 and then encoded a message. 

COMP6021 Class 03.2 - 日本語 and 💔

We continued our looked at Unicode. We looked at how writing works in Japanese, and briefly mentioned Emoji.

COMP6021 Class 03.1 - I ♥日本

We looked at UTF-8.

I gave students a UTF-8 message to decode. 49 E2 99 A5 E6 97 A5 E6 9C AC
I think they got the hang of it.

01001001 11100010:10011001:10100101 11100110:10010111:10100101  11100110:10011100:10101100

I  11100010:10011001:10100101 11100110:10010111:10100101 11100110:10011100:10101100
remove markers for leading and continuation bytes 

I  0010011001100101 0110010111100101  0110011100101100

I 2665 65E5 672C

I ♥日本

COMP6021 Class 02.4 - Zombies, Semaphore & ASCII

We looked at some solutions for the traffic light zombie code and considered some advantages and disadvantages.

We looked at Braille, Semaphore, ASCII, DOS Code Pages, and extended-ASCII

Next up: Unicode

COMP6021 Class 02.3 - Negative Numbers

We played Binary Bingo, but the winner wasn't aware that he had won.

We looked at One's Complement and Two's Complement representations of integers. I explained why they were better that sign & magnitude representations. We looked at using offset binary for awkward situations.  I briefly mentioned IEEE Floating Point, but we won't be going into that. 

We began our look at representing text. I outlined the problems facing Outpost 19 after an attack by the zombie hoard, and asked students to devise an efficient communication system for the traffic lights. 

COMP6021 Binary & Hex Tutorial

This video is a great refresher if you've forgotten how binary and hex work.

COMP6021 Class 02.2 - The Sock on the Door

This was, in fact, our first class.

I introduced the module and talked a little bit about the assessment.

We look at how bits can be used to represent different numbers of things or state, depending on how many bits there are.

We looked at how bits can be used to represent positive integers, and represent integers that may be negative (sign & magnitude)

Slides:

Next up: two's compliment

Improvements to JPEG Compression

http://arstechnica.com/information-technology/2014/07/we-dont-need-new-image-formats-mozilla-works-to-build-a-better-jpeg/

COMP6021 Final Exam

The final exam was today at 1000.

Students will have their results when they are all published together. I don't plan to publish the results of the CA component in the meantime.

I hope you all enjoyed the module. It was a bit of a stretch for some of you. But trying new things is always a good idea. It's been a pleasure doing business with you.

Good luck with your future plans.