Wednesday, September 10, 2008

"Life's But A Walking Shadow..."

I wonder if Shakespeare would find this as absolutely fascinating as I do: tracking people by studying how they move. The new science of Gait Analysis:
By analysing the movements of human shadows in aerial and satellite footage, JPL engineer Adrian Stoica says it should be possible to identify people from the way they walk - a technique called gait analysis, whose power lies in the fact that a person's walking style is very hard to disguise.

Video taken from above shows only people's heads and shoulders, which makes measuring the characteristic length and rhythm of a person's stride impossible. That's not true of shadows, though, Stoica told a security conference in Edinburgh, UK, last month. Shadows, he says, provide enough gait data to deduce a positive ID. To prove it, he has written software that recognises human movement in aerial and satellite video footage. It isolates moving shadows and uses data on the time of day and the camera angle to correct shadows if they are elongated or foreshortened. Regular gait analysis is then applied to identify people. In tests on footage shot from the sixth floor of a building, Stoica says his software was indeed able to extract useful gait data.
Our fingerprints are unique; no matter how similar they may be, they will still be different. Since our hands are the tools our mind uses to create things, this entails that what each person does will be created in a unique way... it's shape will have our individual "fingerprints" all over it.

I remember reading somewhere that a person's toes have similarly unique markings on them as our fingertips do, but it's rather impractical to catalogue them or use them to identify people, because we never go around barefoot. The romantic in me finds it fascinating that our unique feet propel us forward in unique ways, creating unique rhythms, leaving unique marks attesting to our irreplaceable uniqueness, and our consequent value as individuals.

But then, people are always saying that I march to a different drummer...

[thanks to MHA at Flares Into Darkness]

3 comments:

truepeers said...

My fear is a Ministry of Not-too-silly Walks

Charles Henry said...

There is an actual science to walking, it's called "Proprioception".

It's a skill that's taught to people who lost the use of their legs, usually through an accident, and through advances in medical science have regained the potential for ambulatory movement once more. These patients have to learn the patience to learn to walk all over again.

What's interesting is that it is half-taught, half-learned, with the help of a "professional", who helps the student step by step, if you'll pardon the expression...

A question I enjoy asking parents, is for them to try and measure, from their experience, whether it's more accurate to say their child was taught to walk, or whether that child learned how to walk. Do they really do it all by themselves?

Or, as with accident victims being given renewed access to renewed limbs, is it some indeterminable combination of guiding hand and independant study.

From my own dim memories of watching my brother and sister learn to walk, I remember feeling struck by what seemed like their instinctive knowledge that they should be walking, but not having the knowledge as to how that works...

This is a long way 'round to your joke: since there's "something to know", that might indeed mean that there's "Something to Bureaucratize", "Something to Credentialize", and "Something to Govern"...! :)

Dag said...

"Proprioception" was also a trendy technique in Rhetoric some decades ago in 'getting people in touch with their feelings' as they compose.

The things I forget as I amble lonely as a cloud down the nights and down the days.