from light to enlightenment

Kees van Overveld

From Light to From Light to EnlightenmentEnlightenment

Edition Honours Class ‘Big Images’ TU/e 2014Edition Honours Class ‘Big Images’ TU/e 2014

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Kees van Overveld

From Light to Enlightenment From Light to Enlightenment Introduction: what is looking?

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Exercise1.

• Describe in at most one sentence (<20 words) the essence of what you will see next.

‘I see …’

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Kees van Overveld

Introduction: what is ‘looking’?

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Anwers:1. I see the light of the beamer being reflected from the screen

2. I see a distribution of light shades in the middle, brownish near the borders

3. I see mainly smooth color distributions, granular in the middle and patches near the borders

4. I see few light, rounded, symmetric 2D shapes in the middle and a rounded triangle in the lower left

5. I see a roughly spherical shape in the middle and few flat, laying 3D shapes underneath

6. I see a cup of cappuccino and a newspaper

7. I see the cup being almost full and the newspaper not (yet) opened

8. I see the careless beginning of a promising holiday in Italy

From Light to Enlightenment From Light to Enlightenment

Kees van Overveld

Introduction: what is ‘looking’??

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Answers:1. I see the light of the beamer being reflected from the screen

2. I see a distribution of shades of grey

3. I see mainly smooth distributions of grey, granular in places

4. I see few dark lines, few swirls, blotches and scratches

5. I see a – presumably – flat surface with some black shapes in it

6. I see some traces of elementary particles in a bubble chamber

7. I see a reaction between sub-atomic particles with various charges and masses, with lacking momentum

8. I see the first ever empirical evidence of a neutrino


Kees van Overveld

Introduction: what is an ‘image’?

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Exercise 2.

• For the images of exercise 1, explain where they reside.

• Hint: there are at least 10 different correct answers.


Kees van Overveld


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Answers:• In the museum and in the bubble chamber at the instance of the nuclear

reaction, respectively

• In former downtown lunchroom Peacock (‘Heuvelgalerie’), where I took the photograph, and the Wikipedia archive, respectively

• At the hard disk of my computer

• In the beamer

• In the space between the beamer and the screen, or between the screen and your eyes

• In your eye

• In your retina

• In your brain

• In your mind

• In the sound waves in this room while we are talking about them


Kees van Overveld


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We are certain that an image may reside in our head (‘I dream therefore I see’: immediate access to our internal virtual subjective omnimax theatre)

All other answers apply only under certain circumstances

So: the only thing that holds with certainty for each image, is that it has a mental, and therefore subjective representation.



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Two problems:1. We don’t know how something looks

in reality

Mutually parallel or perpendicular lines or

curves?


Kees van Overveld


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Two problems: 2. We don’t know what is to be seen in someone else’s private theatre


Kees van Overveld


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How could we ever intersubjectively know something about images???


Kees van Overveld


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Answer:

Thanks to the miracle of equivalence and the tendency of clustering, innate in our brains.



These are more similar …

.. .than these

‘being similar’ ’color’



Answer:



These are more similar …

… than these

‘being similar’ ’shape’



Answer:



These are more similar

…

… than these

‘being similar’ size’



Answer:



Preliminar conclusion:

A visible property

(‘color’, ‘shape’, ‘size’, …)

is the same thing as

‘a way of clustering’

or

an equivalence relation




Q: what is an equivalence relation?

A: a statement about relating two elements in a set, e.g. : ‘equally heavy’, ‘having the same father’, ‘is connected to’, …

… where this relation is

Reflective M(a,a)

Symmetric M(a,b) M(b,a)

Transitive M(a,b) & M(b,c) M(a,c)




Example (‘same amount’):

~ ~ ~ …

~ …~~

The class of all sets containing three elements, simply called ‘THREE’

The class of all sets containing four elements, simply called ‘FOUR’




So:

Equivalence relations bring forward classes of elements, where all elements in a class are mutually equivalent, so called Equivalence classes.

Equivalence classes are disjoint and covering.

An equivalence class is a convenient way to define something abstract, such as THREE or FOUR, being equivalence classes of ‘equally many’.




Apply to images:

•‘Looks similar to’ is (almost) an equivalence relation.

•‘Looks similar w.r.t. color’ has equivalence classes RED, GREEN, … etc

•‘Looks similar w.r.t. shape’ has equivalence classes ROUND, SQUARE, … etc

•‘Looks similar w.r.t. size’ has equivalence classes LARGE, SMALL, … etc




Apply to images:

•‘Is similar to’ is (almost) an equivalence relation ….

Similar to..similar to..Similar toSimilar to

… does not look similar to

… but not quite: transitivity only holds in approximation.

… this is also true for textures, shapes, 3D surfaces, objects and relalions and meaning

VARIANTS: the variety within one equivalence class

INVARIANTS: that what distinguishes one equivalence class from another

The terminology to argue about properties of images


Introduction: what is an ‘image’?This is an Inevitable shortcoming of our brain (and every measuring instrument), but at the same time an evolutionary advantage, provided that cluster boundaries have evolutionary meaningful interpretations


Advantage of this ‘trick’ (=describing visible features in terms of

equivalence relations):

We don’t need to bother about the essential meaning of ‘red’ (just as we don’t need to bother about the essential meaning of ‘three’).

In stead, we can concentrate on

• interpretation of ‘is similar to’: kinds of similarities

• identifying variants

• identifying invariants




There are many interpretations of ‘is similar to’ or ‘makes me think of’ (jigSaw!)

Common to all:

Every describable feature of an image is a <here-this> pair,

Where ‘here’ denotes a location and ‘this’ is some equivalence class.



Kees van Overveld

Inleiding: wat is een beeld?

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Here is blue

Here is blue-white stripes

Here is saxofone

Here is cylindrical

Here is ellipse

Here is bigger than

Here is tasteless cliché (or: here is recommendation to buy porcellain statuette)


Kees van Overveld

Image features in layers

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Proposal: let us group ‘this’-s in groups

Groups have an ordering

Properties in group n ‘follow’ (or ‘build on’) properties in group n-1

… in what sense ‘follow’?

Consider a process of visual communication, and study coding and decoding


Kees van Overveld

4A. Electrical currents in wire4A. Electrical

currents in wire

1.Come and drink coffee

with me

1.Come and drink coffee

with me

2. Sequence of characters

typed onto keyboard

2. Sequence of characters

typed onto keyboard

3. Bits en bytes3. Bits en bytes

4B. Electronic detectionn

4B. Electronic detectionn

7.Meaning of themessage

7.Meaning of themessage

6. Letters on a screen6. Letters

on a screen

5. Software5. Software

physical communicationphysical communication

virtual communication IIIvirtual communication III

virtual communication IIvirtual communication II

virtual communication Ivirtual communication I

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Kees van Overveld

representations:

Difficult to define, but:

•One representation can be converted into another oen

•Can be replaced by other representations where lower- and higher layers stay the same (variants!)

•Occur in a sequence of representation conversions, together fulfilling some purpose (where invariants, necessary for that purpose, stay the same)

•In images: any representation can be written out as a series of here-this pairs

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In the example:

Variants: color hue, reflectivity, thickness of the border, …

Invariants: color saturation, shape, meaning,…


Kees van Overveld

representations in the context of communication:•1st sequence of representations: sender

•2nd sequence of representations: receiver

•Sender: initiates process with initial communication-impuls or intention

•Receiver: concludes the process with understanding of (and perhaps response to) the message

•Sender and receiver are connected with a physical link

•Virtual communications occur between any two intermediate representations

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Kees van Overveld

4A. 4A.

1. 1.

2. R2. R

3. R’ encodes R3. R’ encodes R

4B. 4B.

7. 7.

6. R’ decodes R6. R’ decodes R

5. R5. R

physical communicationphysical communication

virtual communicationvirtual communication



Representation conversion






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Kees van Overveld

Which layers form a layered communication model for visual communication?

•Lower most: light rays (physical communication)

•Top most layer: intention and effect

Emitting light raysEmitting light rays

Cause and/or intentiong

Cause and/or intentiong

Meaning and/oreffect

Meaning and/oreffect

Light raysLight rays

The net effect of visual communicationThe net effect of visual communication

Reception of light raysn

Reception of light raysn

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Kees van Overveld

A 2-layer model is too naive:•We need additional layers to talk about

•Representations in terms of …

•Colors, textures, shapes, surfaces, objects, relations and meaning

•Representation conversions such as …

•Sending, reflecting and receiving light

•Sampling and discretisation

•Rendering and finding boundaries

•Interpreting 2D as projected 3D

•Understanding, recognizing and classifying objects and relations among them

•Therefore we propose 8 layers:-32-


Kees van Overveld

Color distributions

shapes

surfaces

objects

relations

meaning

Light rays

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texture



Summary of essential concepts:

•Clustering: natural tendency of the brain

•Properties and values: features that cause clusters to occur

•Here-this pairs: an image as a collection of here-this pairs

•Equivalence: way to deal with the intersubjectivity-problem

•Equivalence classes: collection of indistinguishable values for a given property

•Variants and invariants: what is lost, resp. preserved in representation conversion

•Coding and decoding: takes place in sender and receiver, respectively

•Physical and virtual communication

•Layers with representations and representation conversions


from light to enlightenment

Documents

enlightenment introduction

sentence kees van overveld

italyfrom light

neutrinofrom light

themfrom light

realityfrom light

distribution of light

black shapes