Reflectance curves of some common foods. Spectral colors. What is colour? 11/4/11
|
|
- Kathlyn Johns
- 6 years ago
- Views:
Transcription
1 Colour Vision I: The re0nal basis of colour vision and the inherited colour vision deficiencies Prof. Kathy T. ullen What is colour? What physical aspect of the world does our sense of colour inform us about? cgill Vision Research (H4.14) Dept. of Ophthalmology h>p:// 28 th Sept 2011 Spectral colors Reflectance curves of some common foods Reflectance (percent) emon Orange Tomato Cabbage Violet Indigo Blue Green Yellow Orange Red Wavelength (nm) 1
2 The colour circle What is colour? Colour vision allows us to distinguish between surfaces with different spectral reflectances White light is produced by mixing three colours How do we see colour? 2
3 11/4/11 ixing red and green lights to match yellow: Principle of Trichromacy ixing together three coloured lights in suitable proportions enables us to make an exact match to any other colour The 3 mixing lights are called primaries A B C A and B. Green and red lights on the top are mixed by the subject to match the yellow light presented on the bottom. C. The red-green mixture perfectly matches the yellow. The match is called metameric - meaning that identical colour sensations are produced even though the stimuli are physically different mixing lights The mixture in C as it appears to a deuteranomalous observer. test light to be matched JW Three cones types of human retina: AN JW 4 The Human Cone osaic False color images of the arrangement of human cones taken 1 deg from the living fovea using an Adaptive Optics Scanning aser Ophthalmoscope. The bottom right image is from acaque monkey. From the lab of Austin Roorda UC Berkeley. acaque monkey 3
4 The distribution of rods and cones across the retina: the receptor mosaic Fovea Periphery Distribution of rods and cones (120 million rods and 5 million cones) visual eccentricity (deg) spatial density (cells/square mm) macula lutea cones rods Figure 2.16 (Right) The mosaic of rods and cones in the peripheral retina of a monkey. The small circles are rods and the larger ones, cones. The cones appear larger because the retina has been sliced across the receptor s inner segments, which are fatter for the cones compared to the rods, in the peripheral retina. The cones that are stained yellow are the S-cones. (From deonasterio et al., 1981.) retinal eccentricity (mm) Spectral sensitivities of, & S cones A single type of photoreceptor cannot signal colour 100 og relative sensitivity edium Short ong Relative absorbance % Wavelength (nm) (nm) 4
5 Response curve for a single receptor Principle of Univariance Relative absorbance % = 2 (2) The response of a photoreceptor to any wavelength can be matched to any other wavelength simply by adjusng the relave intensies of the two smuli Therefore: any single receptor type is colour blind Wavelength (nm) Response curve for a two receptor system How is colour coded? 100 relative absorbance % Cone 1 Cone Wavelength Each colour produces a unique pattern of relative activities in the three cone types 5
6 Relative absorbancy The basis of colour mixing in a two receptor (dichromatic) system ights W (nm) Each light is absorbed by the and cones in a certain proportion. Relative absorbancy The basis of colour mixing in a two receptor (dichromatic) system ights W (nm) Each light is absorbed by the and cones in a certain proportion. Receptors : Receptors : A dichromatic system requires 2 mixing lights A trichromatic (three receptor) system requires 3 mixing lights (primaries) Relative absorbancy Receptors The basis of colour mixing in a two receptor (dichromatic) system : ights W (nm) :1 95 1:1 The mixture of red and green light looks the same as the yellow light because the red-green mixture and the yellow the same proportional absorptions in the and cones A dichromatic system requires 2 mixing lights A trichromatic (three receptor) system requires 3 mixing lights (primaries) Colours with different wavelength distributions look identical if they produce the same ratio of absorptions in the, and S cone types Colours with different wavelength distributions look different if they produce different absorptions and hence different patterns of activity in the three cone types 6
7 Question: How does the brain work, in 5 words or less? Answer: Brain cells fire in patterns Inherited color vision deficiencies Quote from Harvard (and former cgill) neuroscientist Stephen Pinker interviewed on the Colbert Report. Colour vision is computed from the pattern of activity in the three cone types and is one of the best understood examples of a pattern code. etameric (matched) colour pairs for colour deficient observers ixing red and green lights to match yellow (Raleigh match): A B C A and B. Green and red lights on the top are mixed by the subject to match the yellow light presented on the bottom. C. The red-green mixture perfectly matches the yellow. The mixture in C as it appears to a deuteranomalous observer. 7
8 45 or spots Ishihara test for RG color blindness 29 or spots Inherited color vision deficiencies 6 or spots 56 in both Systematic and predictable losses Both eyes affected ale - sex linked for & (red-green) deficiencies Genetic S cone deficiencies are autosomal and rare - many are undetected or are acquired disorders Color vision tests may not diagnose achromats Trichromats Trichromats One of the three cone types is anomalous Three colours are required to match any other See a full range of colours, but with poorer discrimination in some regions Types Protanomalous = anomalous cones 1 % (m) Deuteranomalous = anomalous cones 5 %(m) Tritanomalous = incidence unknown 8
9 Dichromats One of the three cone types is missing Dichromats Only need two colours to match any other Sees a much reduced range of colours Types Protanope = lacks cones 1% (male) Deuteranope = lacks cones 1% (male) Tritanope = lacks S cones 0.002%? Genes for the (OPN1W) & (OPN1W) cone pigments lie nose to tail on the Q arm of the X chromosome. Frequent mutations occur making these the most rapidly mutating genes in the human genome onochromats No colour vision: any colour matched with any other Rod monochromat (0.003%) (complete achromatopsia) All cones are functionally absent: low acuity, photophobia and nystagmus Blue cone monochromat (incomplete achromatopsia or atypical monochromat) Only S cones are present (0.001%): low acuity, no photophobia, no nystagmus. Worse with artificial illumination. 9
10 11/4/11 onochromats Difficult to differentiate complete vs incomplete types Incomplete may use colour names effectively Incomplete may perform OK on some standard colour tests Autosomal mutations CNGA3 (incomplete achromatopsia), CNGB3, and GNAT2 Original Deuteranope Protanope Tritanope Original Deuteranope Protanope Tritanope 10
Spectral colors. What is colour? 11/23/17. Colour Vision 1 - receptoral. Colour Vision I: The receptoral basis of colour vision
Colour Vision I: The receptoral basis of colour vision Colour Vision 1 - receptoral What is colour? Relating a physical attribute to sensation Principle of Trichromacy & metamers Prof. Kathy T. Mullen
More informationQuestion From Last Class
Question From Last Class What is it about matter that determines its color? e.g., what's the difference between a surface that reflects only long wavelengths (reds) and a surfaces the reflects only medium
More informationHow do photoreceptors work?
How do photoreceptors work? Convert energy from light into nerve signals No easy feat!! 200 femtoseconds!! Phototransduction Isomerization Opsin - transducin Transducin - PDE PDE - cgmp to GMP Low cgmp
More informationColor Perception. Color, What is It Good For? G Perception October 5, 2009 Maloney. perceptual organization. perceptual organization
G892223 Perception October 5, 2009 Maloney Color Perception Color What s it good for? Acknowledgments (slides) David Brainard David Heeger perceptual organization perceptual organization 1 signaling ripeness
More informationColor Deficiency ( Color Blindness )
Color Deficiency ( Color Blindness ) Monochromat - person who needs only one wavelength to match any color Dichromat - person who needs only two wavelengths to match any color Anomalous trichromat - needs
More informationSEEING. Seeing lecture 2 The retina and colour vision. Dr John S. Reid Department of Physics University of Aberdeen
SEEING Seeing lecture 2 The retina and colour vision Dr John S. Reid Department of Physics University of Aberdeen 1 The retina Forming an image on the back of the eye is the easy part. Seeing the image
More informationOPTO 5320 VISION SCIENCE I
OPTO 5320 VISION SCIENCE I Monocular Sensory Processes of Vision: Color Vision Ronald S. Harwerth, OD, PhD Office: Room 2160 Office hours: By appointment Telephone: 713-743-1940 email: rharwerth@uh.edu
More informationAdditive. Subtractive
Physics 106 Additive Subtractive Subtractive Mixing Rules: Mixing Cyan + Magenta, one gets Blue Mixing Cyan + Yellow, one gets Green Mixing Magenta + Yellow, one gets Red Mixing any two of the Blue, Red,
More informationColor. Bilkent University. CS554 Computer Vision Pinar Duygulu
1 Color CS 554 Computer Vision Pinar Duygulu Bilkent University 2 What is light? Electromagnetic radiation (EMR) moving along rays in space R(λ) is EMR, measured in units of power (watts) λ is wavelength
More informationSlide 1. Slide 2. Slide 3. Light and Colour. Sir Isaac Newton The Founder of Colour Science
Slide 1 the Rays to speak properly are not coloured. In them there is nothing else than a certain Power and Disposition to stir up a Sensation of this or that Colour Sir Isaac Newton (1730) Slide 2 Light
More informationHW- Finish your vision book!
March 1 Table of Contents: 77. March 1 & 2 78. Vision Book Agenda: 1. Daily Sheet 2. Vision Notes and Discussion 3. Work on vision book! EQ- How does vision work? Do Now 1.Find your Vision Sensation fill-in-theblanks
More informationSensation, Part 4 Gleitman et al. (2011), Chapter 4
Sensation, Part 4 Gleitman et al. (2011), Chapter 4 Mike D Zmura Department of Cognitive Sciences, UCI Psych 9A / Psy Beh 11A February 20, 2014 T. M. D'Zmura 1 From last time T. M. D'Zmura 2 Rod Transduction
More informationTEACH THE CORRECT COLOR THEORY SCHOOL
Page 1 of 7 TEACH THE CORRECT COLOR THEORY IN SCHOOL Teachers in public schools are still teaching the wrong color theory to children. Here is a list of reasons why this is done, why it is wrong for teachers
More informationThe best retinal location"
How many photons are required to produce a visual sensation? Measurement of the Absolute Threshold" In a classic experiment, Hecht, Shlaer & Pirenne (1942) created the optimum conditions: -Used the best
More informationAchromatic and chromatic vision, rods and cones.
Achromatic and chromatic vision, rods and cones. Andrew Stockman NEUR3045 Visual Neuroscience Outline Introduction Rod and cone vision Rod vision is achromatic How do we see colour with cone vision? Vision
More informationVision. PSYCHOLOGY (8th Edition, in Modules) David Myers. Module 13. Vision. Vision
PSYCHOLOGY (8th Edition, in Modules) David Myers PowerPoint Slides Aneeq Ahmad Henderson State University Worth Publishers, 2007 1 Vision Module 13 2 Vision Vision The Stimulus Input: Light Energy The
More informationIII: Vision. Objectives:
III: Vision Objectives: Describe the characteristics of visible light, and explain the process by which the eye transforms light energy into neural. Describe how the eye and the brain process visual information.
More informationVisual Perception. human perception display devices. CS Visual Perception
Visual Perception human perception display devices 1 Reference Chapters 4, 5 Designing with the Mind in Mind by Jeff Johnson 2 Visual Perception Most user interfaces are visual in nature. So, it is important
More informationThe Photoreceptor Mosaic
The Photoreceptor Mosaic Aristophanis Pallikaris IVO, University of Crete Institute of Vision and Optics 10th Aegean Summer School Overview Brief Anatomy Photoreceptors Categorization Visual Function Photoreceptor
More informationSeeing and Perception. External features of the Eye
Seeing and Perception Deceives the Eye This is Madness D R Campbell School of Computing University of Paisley 1 External features of the Eye The circular opening of the iris muscles forms the pupil, which
More informationAP PSYCH Unit 4.2 Vision 1. How does the eye transform light energy into neural messages? 2. How does the brain process visual information? 3.
AP PSYCH Unit 4.2 Vision 1. How does the eye transform light energy into neural messages? 2. How does the brain process visual information? 3. What theories help us understand color vision? 4. Is your
More informationVictor Ostromoukhov Université de Montréal. Victor Ostromoukhov - Université de Montréal
IFT3355 Victor Ostromoukhov Université de Montréal full world 2 1 in art history Mondrian 1921 The cave of Lascaux About 17000 BC Vermeer mid-xvii century 3 is one of the most effective visual attributes
More informationVisual Imaging and the Electronic Age Color Science
Visual Imaging and the Electronic Age Color Science Grassman s Experiments & Trichromacy Lecture #5 September 5, 2017 Prof. Donald P. Greenberg Light as Rays Light as Waves Light as Photons What is Color
More informationHue Do You Think Hue Are?
Hue Do You Think Hue Are? The Properties of Color There are three fundamental properties by which color is characterized: hue, value and chroma. We ve been discussing value. Now Introducing Hue! Who What
More informationPhysiology of Vision The Eye as a Sense Organ. Rodolfo T. Rafael,M.D. Topics
Physiology of Vision The Eye as a Sense Organ Rodolfo T. Rafael,M.D. www.clinicacayanga.dailyhealthupdates.com 1 Topics Perception of Light Perception of Color Visual Fields Perception of Movements of
More informationVision IV. Overview of Topics. Overview of Topics. Colour Vision
Vision IV Colour Vision Chapter 11 in Chaudhuri 1 1 Overview of Topics Overview of Topics "Avoid vertebrates because they are too complicated, avoid colour vision because it is much too complicated, and
More informationVision IV. Overview of Topics. Evolution of Vision. Overview of Topics. Colour Vision
Overview of Topics Vision IV Colour Vision Chapter 11 in Chaudhuri "Avoid vertebrates because they are too complicated, avoid colour vision because it is much too complicated, and avoid the combination
More informationVision. The eye. Image formation. Eye defects & corrective lenses. Visual acuity. Colour vision. Lecture 3.5
Lecture 3.5 Vision The eye Image formation Eye defects & corrective lenses Visual acuity Colour vision Vision http://www.wired.com/wiredscience/2009/04/schizoillusion/ Perception of light--- eye-brain
More informationVisual Perception. Jeff Avery
Visual Perception Jeff Avery Source Chapter 4,5 Designing with Mind in Mind by Jeff Johnson Visual Perception Most user interfaces are visual in nature. So, it is important that we understand the inherent
More informationCreative Computing II
Creative Computing II Christophe Rhodes c.rhodes@gold.ac.uk Autumn 2010, Wednesdays: 10:00 12:00: RHB307 & 14:00 16:00: WB316 Winter 2011, TBC Ambiguity Image Walter Ehrenstein (1899 1961) Zeitschrift
More informationFuture Electronics EZ-Color Seminar. Autumn Colour Technology
Polymer Optics Ltd. 6 Kiln Ride, Wokingham Berks, RG40 3JL, England Tel/Fax:+44 (0)1189 893341 www.polymer-optics.co.uk Future Electronics EZ-Color Seminar Autumn 2007 Colour Technology Mike Hanney Technical
More informationColor. Fredo Durand Many slides by Victor Ostromoukhov. Color Vision 1
Color Fredo Durand Many slides by Victor Ostromoukhov Color Vision 1 Today: color Disclaimer: Color is both quite simple and quite complex There are two options to teach color: pretend it all makes sense
More informationProf. Feng Liu. Winter /09/2017
Prof. Feng Liu Winter 2017 http://www.cs.pdx.edu/~fliu/courses/cs410/ 01/09/2017 Today Course overview Computer vision Admin. Info Visual Computing at PSU Image representation Color 2 Big Picture: Visual
More informationCS 544 Human Abilities
CS 544 Human Abilities Color Perception and Guidelines for Design Preattentive Processing Acknowledgement: Some of the material in these lectures is based on material prepared for similar courses by Saul
More informationPERCEIVING COLOR. Functions of Color Vision
PERCEIVING COLOR Functions of Color Vision Object identification Evolution : Identify fruits in trees Perceptual organization Add beauty to life Slide 2 Visible Light Spectrum Slide 3 Color is due to..
More informationINVESTIGATIVE OPHTHALMOLOGY. Densitometry of pigments in rods and cones of normal and color defective subjects
June 1966 Volume 5, Number 3 INVESTIGATIVE OPHTHALMOLOGY Densitometry of pigments in rods and cones of normal and color defective subjects W. A. H. Rushton I Hecht's Photochemical Theory may fairly claim
More informationImage and video processing (EBU723U) Colour Images. Dr. Yi-Zhe Song
Image and video processing () Colour Images Dr. Yi-Zhe Song yizhe.song@qmul.ac.uk Today s agenda Colour spaces Colour images PGM/PPM images Today s agenda Colour spaces Colour images PGM/PPM images History
More informationMEASURING WAVELENGTH DISCRIMINATION THRESHOLD ALONG THE ENTIRE VISIBLE SPECTRUM
PERIODICA POLYTECHNICA SER. MECH. ENG. VOL. 45, NO. 1, PP. 41 48 (2001) MEASURING WAVELENGTH DISCRIMINATION THRESHOLD ALONG THE ENTIRE VISIBLE SPECTRUM Ádám KRÚDY and Károly LADUNGA Department of Precision
More informationDigital Image Processing
Digital Image Processing Lecture # 3 Digital Image Fundamentals ALI JAVED Lecturer SOFTWARE ENGINEERING DEPARTMENT U.E.T TAXILA Email:: ali.javed@uettaxila.edu.pk Office Room #:: 7 Presentation Outline
More informationThe Human Visual System. Lecture 1. The Human Visual System. The Human Eye. The Human Retina. cones. rods. horizontal. bipolar. amacrine.
Lecture The Human Visual System The Human Visual System Retina Optic Nerve Optic Chiasm Lateral Geniculate Nucleus (LGN) Visual Cortex The Human Eye The Human Retina Lens rods cones Cornea Fovea Optic
More informationexcite the cones in the same way.
Humans have 3 kinds of cones Color vision Edward H. Adelson 9.35 Trichromacy To specify a light s spectrum requires an infinite set of numbers. Each cone gives a single number (univariance) when stimulated
More informationComputer Graphics Si Lu Fall /27/2016
Computer Graphics Si Lu Fall 2017 09/27/2016 Announcement Class mailing list https://groups.google.com/d/forum/cs447-fall-2016 2 Demo Time The Making of Hallelujah with Lytro Immerge https://vimeo.com/213266879
More informationCS 565 Computer Vision. Nazar Khan PUCIT Lecture 4: Colour
CS 565 Computer Vision Nazar Khan PUCIT Lecture 4: Colour Topics to be covered Motivation for Studying Colour Physical Background Biological Background Technical Colour Spaces Motivation Colour science
More informationWe have already discussed retinal structure and organization, as well as the photochemical and electrophysiological basis for vision.
LECTURE 4 SENSORY ASPECTS OF VISION We have already discussed retinal structure and organization, as well as the photochemical and electrophysiological basis for vision. At the beginning of the course,
More informationBettina Selig. Centre for Image Analysis. Swedish University of Agricultural Sciences Uppsala University
2011-10-26 Bettina Selig Centre for Image Analysis Swedish University of Agricultural Sciences Uppsala University 2 Electromagnetic Radiation Illumination - Reflection - Detection The Human Eye Digital
More informationSYDE 575: Introduction to Image Processing. Adaptive Color Enhancement for Color vision Deficiencies
SYDE 575: Introduction to Image Processing Adaptive Color Enhancement for Color vision Deficiencies Color vision deficiencies Statistics show that color vision deficiencies affect 8.7% of the male population
More informationDigital Image Processing
Part 1: Course Introduction Achim J. Lilienthal AASS Learning Systems Lab, Dep. Teknik Room T1209 (Fr, 11-12 o'clock) achim.lilienthal@oru.se Course Book Chapters 1 & 2 2011-04-05 Contents 1. Introduction
More informationChapter 2: The Beginnings of Perception
Chapter 2: The Beginnings of Perception We ll see the first three steps of the perceptual process for vision https:// 49.media.tumblr.co m/ 87423d97f3fbba8fa4 91f2f1bfbb6893/ tumblr_o1jdiqp4tc1 qabbyto1_500.gif
More informationColour + Perception. CMPT 467/767 Visualization Torsten Möller. Pfister/Möller
Colour + Perception CMPT 467/767 Visualization Torsten Möller Recommended Reading http://www.stonesc.com/ 2 Where / What 3 Based on slide from Mazur Contours & Texture C. Ware, Visual Thinking for Design
More informationVision and Color. Reading. Optics, cont d. Lenses. d d f. Brian Curless CSE 557 Autumn Good resources:
Reading Good resources: Vision and Color Brian Curless CSE 557 Autumn 2015 Glassner, Principles of Digital Image Synthesis, pp. 5-32. Palmer, Vision Science: Photons to Phenomenology. Wandell. Foundations
More informationVision and Color. Brian Curless CSE 557 Autumn 2015
Vision and Color Brian Curless CSE 557 Autumn 2015 1 Reading Good resources: Glassner, Principles of Digital Image Synthesis, pp. 5-32. Palmer, Vision Science: Photons to Phenomenology. Wandell. Foundations
More informationLight and Colour. Light as part of the EM spectrum. Light as part of the EM spectrum
Light and Colour Prof. Grega Bizjak, PhD Laboratory of Lighting and Photometry Faculty of Electrical Engineering University of Ljubljana Light as part of the EM spectrum Visible light can be seen as part
More informationCMPSCI 670: Computer Vision! Color. University of Massachusetts, Amherst September 15, 2014 Instructor: Subhransu Maji
CMPSCI 670: Computer Vision! Color University of Massachusetts, Amherst September 15, 2014 Instructor: Subhransu Maji Slides by D.A. Forsyth 2 Color is the result of interaction between light in the environment
More informationHuman Visual System. Prof. George Wolberg Dept. of Computer Science City College of New York
Human Visual System Prof. George Wolberg Dept. of Computer Science City College of New York Objectives In this lecture we discuss: - Structure of human eye - Mechanics of human visual system (HVS) - Brightness
More informationRetina. Convergence. Early visual processing: retina & LGN. Visual Photoreptors: rods and cones. Visual Photoreptors: rods and cones.
Announcements 1 st exam (next Thursday): Multiple choice (about 22), short answer and short essay don t list everything you know for the essay questions Book vs. lectures know bold terms for things that
More informationPERCEPTUALLY-ADAPTIVE COLOR ENHANCEMENT OF STILL IMAGES FOR INDIVIDUALS WITH DICHROMACY. Alexander Wong and William Bishop
PERCEPTUALLY-ADAPTIVE COLOR ENHANCEMENT OF STILL IMAGES FOR INDIVIDUALS WITH DICHROMACY Alexander Wong and William Bishop University of Waterloo Waterloo, Ontario, Canada ABSTRACT Dichromacy is a medical
More informationReading. Lenses, cont d. Lenses. Vision and color. d d f. Good resources: Glassner, Principles of Digital Image Synthesis, pp
Reading Good resources: Glassner, Principles of Digital Image Synthesis, pp. 5-32. Palmer, Vision Science: Photons to Phenomenology. Vision and color Wandell. Foundations of Vision. 1 2 Lenses The human
More informationColorimetry and Color Modeling
Color Matching Experiments 1 Colorimetry and Color Modeling Colorimetry is the science of measuring color. Color modeling, for the purposes of this Field Guide, is defined as the mathematical constructs
More informationThe Special Senses: Vision
OLLI Lecture 5 The Special Senses: Vision Vision The eyes are the sensory organs for vision. They collect light waves through their photoreceptors (located in the retina) and transmit them as nerve impulses
More informationLecture 8. Human Information Processing (1) CENG 412-Human Factors in Engineering May
Lecture 8. Human Information Processing (1) CENG 412-Human Factors in Engineering May 30 2009 1 Outline Visual Sensory systems Reading Wickens pp. 61-91 2 Today s story: Textbook page 61. List the vision-related
More informationFundamental Optics of the Eye and Rod and Cone vision
Fundamental Optics of the Eye and Rod and Cone vision Andrew Stockman Revision Course in Basic Sciences for FRCOphth. Part 1 Outline The eye Visual optics Image quality Measuring image quality Refractive
More informationThis question addresses OPTICAL factors in image formation, not issues involving retinal or other brain structures.
Bonds 1. Cite three practical challenges in forming a clear image on the retina and describe briefly how each is met by the biological structure of the eye. Note that by challenges I do not refer to optical
More informationVisual System I Eye and Retina
Visual System I Eye and Retina Reading: BCP Chapter 9 www.webvision.edu The Visual System The visual system is the part of the NS which enables organisms to process visual details, as well as to perform
More informationVisibility, Performance and Perception. Cooper Lighting
Visibility, Performance and Perception Kenneth Siderius BSc, MIES, LC, LG Cooper Lighting 1 Vision It has been found that the ability to recognize detail varies with respect to four physical factors: 1.Contrast
More informationDigital Image Processing
Digital Image Processing 6. Color Image Processing Computer Engineering, Sejong University Category of Color Processing Algorithm Full-color processing Using Full color sensor, it can obtain the image
More informationColor, Vision, & Perception. Outline
Color, Vision, & Perception CS 160, Fall 97 Professor James Landay September 24, 1997 9/24/97 1 Outline Administrivia Review Human visual system Color perception Color deficiency Guidelines for design
More informationPSY 214 Lecture # (09/14/2011) (Introduction to Vision) Dr. Achtman PSY 214. Lecture 4 Topic: Introduction to Vision Chapter 3, pages 44-54
Corrections: A correction needs to be made to NTCO3 on page 3 under excitatory transmitters. It is possible to excite a neuron without sending information to another neuron. For example, in figure 2.12
More informationLecture 2 Digital Image Fundamentals. Lin ZHANG, PhD School of Software Engineering Tongji University Fall 2016
Lecture 2 Digital Image Fundamentals Lin ZHANG, PhD School of Software Engineering Tongji University Fall 2016 Contents Elements of visual perception Light and the electromagnetic spectrum Image sensing
More informationDigital Image Processing COSC 6380/4393
Digital Image Processing COSC 6380/4393 Lecture 2 Aug 24 th, 2017 Slides from Dr. Shishir K Shah, Rajesh Rao and Frank (Qingzhong) Liu 1 Instructor TA Digital Image Processing COSC 6380/4393 Pranav Mantini
More informationOrthogonal Relations and Color Constancy in Dichromatic Colorblindness
Orthogonal Relations and Color Constancy in Dichromatic Colorblindness Ralph W. Pridmore* Department of Cognitive Science, Macquarie University, Sydney, NSW, Australia Abstract This paper employs uniform
More informationVision and Color. Reading. Optics, cont d. Lenses. d d f. Brian Curless CSEP 557 Fall Good resources:
Reading Good resources: Vision and Color Brian Curless CSEP 557 Fall 2016 Glassner, Principles of Digital Image Synthesis, pp. 5-32. Palmer, Vision Science: Photons to Phenomenology. Wandell. Foundations
More informationVision and Color. Brian Curless CSEP 557 Fall 2016
Vision and Color Brian Curless CSEP 557 Fall 2016 1 Reading Good resources: Glassner, Principles of Digital Image Synthesis, pp. 5-32. Palmer, Vision Science: Photons to Phenomenology. Wandell. Foundations
More informationLight. intensity wavelength. Light is electromagnetic waves Laser is light that contains only a narrow spectrum of frequencies
Image formation World, image, eye Light Light is electromagnetic waves Laser is light that contains only a narrow spectrum of frequencies intensity wavelength Visible light is light with wavelength from
More informationLIGHT AND LIGHTING FUNDAMENTALS. Prepared by Engr. John Paul Timola
LIGHT AND LIGHTING FUNDAMENTALS Prepared by Engr. John Paul Timola LIGHT a form of radiant energy from natural sources and artificial sources. travels in the form of an electromagnetic wave, so it has
More informationA study of unusual Rayleigh matches in deutan deficiency
Visual Neuroscience ~2008!, 25, 507 516. Printed in the USA. Copyright 2008 Cambridge University Press 0952-5238008 $25.00 doi:10.10170s0952523808080619 A study of unusual Rayleigh matches in deutan deficiency
More informationSpatial Vision: Primary Visual Cortex (Chapter 3, part 1)
Spatial Vision: Primary Visual Cortex (Chapter 3, part 1) Lecture 6 Jonathan Pillow Sensation & Perception (PSY 345 / NEU 325) Princeton University, Fall 2017 Eye growth regulation KL Schmid, CF Wildsoet
More informationStructure of the eye and retina
1 of 10 9/19/2013 11:53 AM Syllabus pdf file Course Schedule Structure of the eye and retina In-class demo: do Virtual Lab activity 3-6 (Visual Path in the Eyeball) 2 of 10 9/19/2013 11:53 AM Focusing,
More informationFig Color spectrum seen by passing white light through a prism.
1. Explain about color fundamentals. Color of an object is determined by the nature of the light reflected from it. When a beam of sunlight passes through a glass prism, the emerging beam of light is not
More informationSlide 4 Now we have the same components that we find in our eye. The analogy is made clear in this slide. Slide 5 Important structures in the eye
Vision 1 Slide 2 The obvious analogy for the eye is a camera, and the simplest camera is a pinhole camera: a dark box with light-sensitive film on one side and a pinhole on the other. The image is made
More informationColor and perception Christian Miller CS Fall 2011
Color and perception Christian Miller CS 354 - Fall 2011 A slight detour We ve spent the whole class talking about how to put images on the screen What happens when we look at those images? Are there any
More informationCapturing Light in man and machine
Capturing Light in man and machine CS194: Image Manipulation & Computational Photography Alexei Efros, UC Berkeley, Fall 2015 Etymology PHOTOGRAPHY light drawing / writing Image Formation Digital Camera
More informationColour. Why/How do we perceive colours? Electromagnetic Spectrum (1: visible is very small part 2: not all colours are present in the rainbow!
Colour What is colour? Human-centric view of colour Computer-centric view of colour Colour models Monitor production of colour Accurate colour reproduction Colour Lecture (2 lectures)! Richardson, Chapter
More informationOPTICAL DEMONSTRATIONS ENTOPTIC PHENOMENA, VISION AND EYE ANATOMY
OPTICAL DEMONSTRATIONS ENTOPTIC PHENOMENA, VISION AND EYE ANATOMY The pupil as a first line of defence against excessive light. DEMONSTRATION 1. PUPIL SHAPE; SIZE CHANGE Make a triangular shape with the
More information19. Vision and color
19. Vision and color 1 Reading Glassner, Principles of Digital Image Synthesis, pp. 5-32. Watt, Chapter 15. Brian Wandell. Foundations of Vision. Sinauer Associates, Sunderland, MA, pp. 45-50 and 69-97,
More informationWhat determines data speed?
PHY385-H1F Introductory Optics Class 12 Outline: Section 5.7, Sub-sections 5.7.1 5.7.6 Fibre-Optics The Human Eye Corrective Lenses Pinhole Camera Camera Depth of Field What determines data speed? Broadband
More informationVision and color. University of Texas at Austin CS384G - Computer Graphics Fall 2010 Don Fussell
Vision and color University of Texas at Austin CS384G - Computer Graphics Fall 2010 Don Fussell Reading Glassner, Principles of Digital Image Synthesis, pp. 5-32. Watt, Chapter 15. Brian Wandell. Foundations
More informationColour. Electromagnetic Spectrum (1: visible is very small part 2: not all colours are present in the rainbow!) Colour Lecture!
Colour Lecture! ITNP80: Multimedia 1 Colour What is colour? Human-centric view of colour Computer-centric view of colour Colour models Monitor production of colour Accurate colour reproduction Richardson,
More informationLight waves of different wavelengths or combinations of wavelengths cause the human eye to detect different colors.
Section 2: Light waves of different wavelengths or combinations of wavelengths cause the human eye to detect different colors. K What I Know W What I Want to Find Out L What I Learned Essential Questions
More informationany kind, you have two receptive fields, one the small center region, the other the surround region.
In a centersurround cell of any kind, you have two receptive fields, one the small center region, the other the surround region. + _ In a chromatic center-surround field, each in innervated by one class
More informationColour. Cunliffe & Elliott, Chapter 8 Chapman & Chapman, Digital Multimedia, Chapter 5. Autumn 2016 University of Stirling
CSCU9N5: Multimedia and HCI 1 Colour What is colour? Human-centric view of colour Computer-centric view of colour Colour models Monitor production of colour Accurate colour reproduction Cunliffe & Elliott,
More informationCOLOR and the human response to light
COLOR and the human response to light Contents Introduction: The nature of light The physiology of human vision Color Spaces: Linear Artistic View Standard Distances between colors Color in the TV 2 How
More informationColor Cameras: Three kinds of pixels
Color Cameras: Three kinds of pixels 3 Chip Camera Introduction to Computer Vision CSE 252a Lecture 9 Lens Dichroic prism Optically split incoming light onto three sensors, each responding to different
More informationBIOPHYSICS OF VISION GEOMETRIC OPTICS OF HUMAN EYE. Refraction media of the human eye. D eye = 63 diopter, D cornea =40, D lens = 15+
BIOPHYSICS OF VISION THEORY OF COLOR VISION ELECTRORETINOGRAM Two problems: All cows are black in dark! Playing tennis in dark with illuminated lines, rackets, net, and ball! Refraction media of the human
More informationVision and Color. Reading. The lensmaker s formula. Lenses. Brian Curless CSEP 557 Autumn Good resources:
Reading Good resources: Vision and Color Brian Curless CSEP 557 Autumn 2017 Glassner, Principles of Digital Image Synthesis, pp. 5-32. Palmer, Vision Science: Photons to Phenomenology. Wandell. Foundations
More informationChapter 2: Digital Image Fundamentals. Digital image processing is based on. Mathematical and probabilistic models Human intuition and analysis
Chapter 2: Digital Image Fundamentals Digital image processing is based on Mathematical and probabilistic models Human intuition and analysis 2.1 Visual Perception How images are formed in the eye? Eye
More informationVision Basics Measured in:
Vision Vision Basics Sensory receptors in our eyes transduce light into meaningful images Light = packets of waves Measured in: Brightness amplitude of wave (high=bright) Color length of wave Saturation
More informationColor Science. CS 4620 Lecture 15
Color Science CS 4620 Lecture 15 2013 Steve Marschner 1 [source unknown] 2013 Steve Marschner 2 What light is Light is electromagnetic radiation exists as oscillations of different frequency (or, wavelength)
More informationToday. Color. Color and light. Color and light. Electromagnetic spectrum 2/7/2011. CS376 Lecture 6: Color 1. What is color?
Color Monday, Feb 7 Prof. UT-Austin Today Measuring color Spectral power distributions Color mixing Color matching experiments Color spaces Uniform color spaces Perception of color Human photoreceptors
More informationOptimizing Performance of AO Ophthalmic Systems. Austin Roorda, PhD
Optimizing Performance of AO Ophthalmic Systems Austin Roorda, PhD Charles Garcia, MD Tom Hebert, PhD Fernando Romero-Borja, PhD Krishna Venkateswaran, PhD Joy Martin, OD/PhD student Ramesh Sundaram, MS
More informationiris pupil cornea ciliary muscles accommodation Retina Fovea blind spot
Chapter 6 Vision Exam 1 Anatomy of vision Primary visual cortex (striate cortex, V1) Prestriate cortex, Extrastriate cortex (Visual association coretx ) Second level association areas in the temporal and
More information