School presentation about image/video compression ?

[e-Pawel]

Hy,

I don't know whether you can help me but maybe you do ;)

As a part of my "a levels" I have to make a presentation. It's up to me what topic I choose, so I consider to make a presentation about image and video compression. The presentation has to take about 20 minutes and it shouldn't be too sophisticated but as simple as possible and its aim is to show in a simple way how image and video compression work.

So here's my first question:
Is this topic ok or will it be way to hard for me to present it?

And here are the others:
I only know that (when using jpeg) the pictures are divided up into 8x8 pix blocks and then they are performed a discretel cosine transform...

So how actually does the compression work? What do I have to search for on the Internet to find suitable information? And please consider that I don't understand a lot (surely way more than a average pc user, but still to less... ;) )

Regards, Pawel

[Guest]

Why are you choosing a topic to present that you know so little about? Choose a topic where you have good knowledge. Then you can project competence and confidence.

[dialysis1]

Google how video compression works. Lots of answers.

[e-Pawel]

Why are you choosing a topic to present that you know so little about?

Well sure, but the presentation is intended to describe the topic in a way as simple as possible. So I don't need to describe all the mathematics operation in all details. And I'm just a student of a very normal school, I'm not expected so much.

Thus I believe my knowledge (and I would learn more) should be more or less adequate - I know more than a average pc user or my informatics teacher.

[Dark Shikari]

If you don't understand basic Fourier mathematics and the associated discrete cosine transform, or don't think you can make everyone in the room understand it in less than 5 minutes, you probably shouldn't be presenting it.

[Guest]

Thus I believe my knowledge (and I would learn more) should be more or less adequate. That's the definition of mediocrity. To excel, you need to exceed expectations.

[JohnnyMalaria]

And here are the others:
I only know that (when using jpeg) the pictures are divided up into 8x8 pix blocks and then they are performed a discretel cosine transform...

So how actually does the compression work?

This is the key to the whole presentation. If you just say "JPEG uses 8 x 8 blocks that are transformed to the discrete cosine transform" then the obvious reply is "So?" or "Why?"

I'll give you one word as a clue for you to start with - Huffman.

For a successful 20-minute presentation, you must keep the information at a high level. Don't get into heavy maths. Try to explain things in real-world terms. Use props - e.g., a cell phone with video capability etc. JPEG compression is complicated but the principles are simple - the skill you need is to reduce it to the few important parts. You don't need to know every detail. You need to know sufficiently more than the audience, particularly to be able to answer any questions with credibility.

I think your topic is interesting - it is relevant to many aspects of every day life. That's an important part of grabbing the audience's attention.

Good luck with it.

[Guest]

This document may help you with concepts:

http://neuron2.net/library/25W_11418_7.pdf

[dstarfire]

Actually, doing a presentation/research project about a topic is one of the best ways to learn more about it. You'll have an easier time explaining it in everyday terms since you'll be only slightly more knowledgable than your audience.

[Guest]

Yeah, but this is his A level exam. That's not the time to be learnng; that's the time to be strutting your stuff.

[e-Pawel]

Thanks a lot to all of you for all the replies.

Yeah, but this is his A level exam. That's not the time to be learnng; that's the time to be strutting your stuff.

I actually have time to prepare the presentation. I suppose that A level exams are completely different in the US or the UK than in Germany, where I attend my school. Beside of the 4 regular exams I also have to prepare a presentation (which look nothing like a regular exam) and it's all up to me what I'm going to present. From now on I have 9 months time to make it.

I think that solely the fact that I choose the subject "informatics " would suffice to excel: other schoolmates picked topics like "music styles and musicians in the epoche of ..." (what isn't very difficult and sophisticated); a friend of mine picked the topic "p2p systems" (but he described it in a way every average pc user can understand; without getting too much into detail and using specialist terms).

So I don't need to get too much into detail and I'm not expected so much most of you probably think (it surely would suffice to present 5-10% of what you know about that topic to get a A-schoolmark ;) )