Page 1 of 1

Maths Help please

Posted: 12 May 2015, 06:31
by Llyfrau
The equation in the attached picture comes from a paper on book scanning mentioned here.

I don't have too much of a problem working with the maths BUT I cannot understand some of the symbols that are being used.
In particular there are two vertical parallel lines that are used throughout this equation. I have never seen anything like them in an equation.
I showed the equation to a retired engineering lecturer in my family and he had never seen anything like them before either.

So what do they mean?

I am building a conventional simple book scanner with a camera and a light rather like the cardboard box version that you are all probably familiar with, but I want to go further and
develop a more portable quick scanner which is why I am looking at this stuff. My conventional scanner works. I have tried it, but i am waiting for delivery of some anti-glare acrylic for the plattern.

If you don't know the answer it would also be useful if you were able to point me in the direction of somewhere else where I could ask.

Re: Maths Help please

Posted: 12 May 2015, 06:52
by duerig
The vertical double-bars means the length of the vector. See: ... idean_norm

I would be very interested to see how far you can get with these techniques. Please post any code and results here.


Re: Maths Help please

Posted: 12 May 2015, 07:07
by Llyfrau
Thanks very much for the explanation. It is a great help especially the wiki link.

I do intend to share stuff that I develop. I may well show off my finalised simple book scanner,for example, because I have a novel substitute for the cardboard box
( I am using it at this very moment to post this message.)

There is a lot to get my head around but first i need to get a full copy of that paper. The version i have is a partial one from Google books.
I needed to see first if the maths was understandable, which it is I think now.