chapter 7. visual objects and data objects 컴퓨터 교육학과 박사과정 차승은 2007. 05....

Chapter 7.Chapter 7.

Visual Objects Visual Objects andand

Data ObjectsData Objects

Chapter 7.Chapter 7.

Visual Objects Visual Objects andand

Data ObjectsData Objects

컴퓨터 교육학과컴퓨터 교육학과박사과정 차승은박사과정 차승은2007. 05. 04.2007. 05. 04.

컴퓨터 교육학과컴퓨터 교육학과박사과정 차승은박사과정 차승은2007. 05. 04.2007. 05. 04.

INC Lab.

For our present purposes, an objectobject can be thought of as any identifiable, separate, and distinct part of the visual world.

Information about visual objects is cognitively stored in a way that ties together critical Features, such as oriented edges and patches of color and texture, so that they can Be identified, visually tracked, and remembered.

For our present purposes, an objectobject can be thought of as any identifiable, separate, and distinct part of the visual world.

Information about visual objects is cognitively stored in a way that ties together critical Features, such as oriented edges and patches of color and texture, so that they can Be identified, visually tracked, and remembered.

1. Introduction1. Introduction

→ Because visual objects cognitively group visual attributes, if we can represent data values as visual features and group these features into visual objects, we will have a very powerful tool for organizing related data.

→ Because visual objects cognitively group visual attributes, if we can represent data values as visual features and group these features into visual objects, we will have a very powerful tool for organizing related data.

INC Lab.

Image-based : matching the visual image

with a snapshot stored in

memory

Image-based : matching the visual image

with a snapshot stored in

memory

1. Introduction1. Introduction

Two theories to explain Object recognitionTwo theories to explain Object recognition

Structured based: primitive 3D forms and the

structural interrelationships

between objects

Structured based: primitive 3D forms and the

structural interrelationships

between objects

→ Two radically different theories have been proposed to explain object recognition.

→ Two radically different theories have been proposed to explain object recognition.

INC Lab.

♪ Experiment 1 : remarkable ability to recall pictorial images

♪ Experiment 2 : Rapid Serial Visual Presentation (RSVP)

♪ Experiment 3 : Attentional blink

♪ Experiment 4 : Recognition VS recall → icon

♪ Experiment 1 : remarkable ability to recall pictorial images

♪ Experiment 2 : Rapid Serial Visual Presentation (RSVP)

♪ Experiment 3 : Attentional blink

♪ Experiment 4 : Recognition VS recall → icon

2. Image – based Object Recognition2. Image – based Object Recognition 2. Image – based Object Recognition2. Image – based Object Recognition

INC Lab.


INC Lab.

The term of Priming : that people can identify objects more easily if they are given prior exposure to some relevant information.

Canonical view : 많은 각각의 사물들은 사물의 식별이 용이하게 해주는 “ Canonical view ” 가 존재

→ we recognize objects by matching the visual information with internally stored view point specific examplars, or “prototypes”.

→ According to this theory, the brain stores a number of key views of objects. → These views are not simple snapshots; they allow recognition despite simple geometric distortions of the image that occur in perspective transformation.

♪♪ However, there are strict limitsstrict limits on the extent to which we can change an image before recognition problems occur. ( ex : face recognition upside-down)

The term of Priming : that people can identify objects more easily if they are given prior exposure to some relevant information.

Canonical view : 많은 각각의 사물들은 사물의 식별이 용이하게 해주는 “ Canonical view ” 가 존재

→ we recognize objects by matching the visual information with internally stored view point specific examplars, or “prototypes”.

→ According to this theory, the brain stores a number of key views of objects. → These views are not simple snapshots; they allow recognition despite simple geometric distortions of the image that occur in perspective transformation.

♪♪ However, there are strict limitsstrict limits on the extent to which we can change an image before recognition problems occur. ( ex : face recognition upside-down)


INC Lab.


INC Lab.

Icon

: visual images are easily recognized after so little exposure.icons in user interfaces should make excellent memory aids.helping us recall the functionality of parts of complex systems.

Icon

: visual images are easily recognized after so little exposure.icons in user interfaces should make excellent memory aids.helping us recall the functionality of parts of complex systems.


Application of Images in User InterfaceApplication of Images in User InterfaceApplication of Images in User InterfaceApplication of Images in User Interface

INC Lab.

Priming

: useful in helping people search for particular patterns in data. The obvious way of doing this is to provide sample images of the kind of pattern being sought and repeating the samples at frequent intervals during the search process.

(ex : using images of sample viruses in medical screening laboratory)

Priming

: useful in helping people search for particular patterns in data. The obvious way of doing this is to provide sample images of the kind of pattern being sought and repeating the samples at frequent intervals during the search process.

(ex : using images of sample viruses in medical screening laboratory)



INC Lab.

Searching an Image Database

: Presenting images rapidly in sequence may be a useful way to allow users to scan picture data-bases.The fact that people can search rapidly for an image in a sequence of up to 10 pictures per second suggests that presenting images using RSVP may be efficient.


: Presenting images rapidly in sequence may be a useful way to allow users to scan picture data-bases.The fact that people can search rapidly for an image in a sequence of up to 10 pictures per second suggests that presenting images using RSVP may be efficient.



INC Lab.


: Contrast this with the usual method of presenting image collections in a regular grid of small thumbnail images. If it is necessary to make an eye movement to fixate each thumbnail image, it will not be possible to scan more than three

to four images per second.


: Contrast this with the usual method of presenting image collections in a regular grid of small thumbnail images. If it is necessary to make an eye movement to fixate each thumbnail image, it will not be possible to scan more than three

to four images per second.



INC Lab.


INC Lab.

3. Structure – based Object Recognition3. Structure – based Object Recognition 3. Structure – based Object Recognition3. Structure – based Object Recognition

Image-based theories of object recognition imply a rather superficial level of analysis of visual objects.

Image-based theories of object recognition imply a rather superficial level of analysis of visual objects.

Yet despite the fact that the images of these two objects are very different fromone another, they can be rapidly recognized as representations of the same object.• • No image-based theory can account for this result.No image-based theory can account for this result.

Yet despite the fact that the images of these two objects are very different fromone another, they can be rapidly recognized as representations of the same object.• • No image-based theory can account for this result.No image-based theory can account for this result.

INC Lab.


Geon Theory컴퓨터 시각의 또 다른 응용으로 물체 인식이 있다 . Biederman [985] 에 따르면 많은 부류의 물체들은 지온 (geon) 이라고 부르는 소수의 기본 구성요소의 집합으로 이루어진다 . 그리하여 이러한 지온에 기반을 둔 시스템들이 고안되었으나 아직까지는 제한된 부류의 물체 인식에만 사용되었다 .

Geon Theory컴퓨터 시각의 또 다른 응용으로 물체 인식이 있다 . Biederman [985] 에 따르면 많은 부류의 물체들은 지온 (geon) 이라고 부르는 소수의 기본 구성요소의 집합으로 이루어진다 . 그리하여 이러한 지온에 기반을 둔 시스템들이 고안되었으나 아직까지는 제한된 부류의 물체 인식에만 사용되었다 .

INC Lab.


Geon TheoryGeon Theory

INC Lab.


Geon Theorysomewhat simplified overview of a neural-network model of structuralobject perception, developed by Hammel and Biederman (1992).

Geon Theorysomewhat simplified overview of a neural-network model of structuralobject perception, developed by Hammel and Biederman (1992).

INC Lab.


Silhouettes

• Silhouettes appear to be especially important in determining how we perceive the structure of objects.

• The fact that simplified line drawings are often silhouettes may, in part, account for our ability to interpret them.

• At some level of perceptual processing, the silhouette boundaries of objects and the simplified line drawings of those objects excite the same neural contour-extraction mechanisms.

Silhouettes

• Silhouettes appear to be especially important in determining how we perceive the structure of objects.

• The fact that simplified line drawings are often silhouettes may, in part, account for our ability to interpret them.

• At some level of perceptual processing, the silhouette boundaries of objects and the simplified line drawings of those objects excite the same neural contour-extraction mechanisms.

INC Lab.


Silhouettes

• Many objects have particular silhouettes that are easily recognizable; think of a teapot, a shoe, a church, a person, or a violin.• These canonical silhouettes are based on a particular view of an object, often from a point at right angles to a major plane of symmetry.

Silhouettes

• Many objects have particular silhouettes that are easily recognizable; think of a teapot, a shoe, a church, a person, or a violin.• These canonical silhouettes are based on a particular view of an object, often from a point at right angles to a major plane of symmetry.

INC Lab.


Silhouettes

• Certain simplified views should be easier to read.• Time is required for detailed information to be perceived.• Simplified line drawings may be most appropriate only when rapid responses are required.

Silhouettes

• Certain simplified views should be easier to read.• Time is required for detailed information to be perceived.• Simplified line drawings may be most appropriate only when rapid responses are required.

INC Lab.

4. Faces4. Faces4. Faces4. Faces

• Faces are special objects in human perception.• Infants learn about faces faster than other objects.• It is as if we are born with visual systems primed to learn to recognize important humans, such as our own mothers.• A specific area of our brains, the right middle fusiform gyrus, is especially important in face perception.

• Faces are special objects in human perception.• Infants learn about faces faster than other objects.• It is as if we are born with visual systems primed to learn to recognize important humans, such as our own mothers.• A specific area of our brains, the right middle fusiform gyrus, is especially important in face perception.

(A) (B)

INC Lab.


• This area is also useful for recognizing other complex

objects, such as automobiles.

• Faces have an obvious importance in communication.

• Certain human expressions are universal

communication signals, correctly interpreted across

cultures and social groups (Ekman and Friesen, 1975).

• This area is also useful for recognizing other complex

objects, such as automobiles.

• Faces have an obvious importance in communication.

• Certain human expressions are universal

communication signals, correctly interpreted across

cultures and social groups (Ekman and Friesen, 1975).

INC Lab.


• Ekman identified six universal expressions: happiness, anger, sadness, disgust, fear, surprise. • The motion of facial features is also important in conveying emotion.• Animated images are necessary to convey a full range of nuanced emotion; it is especially important to show motion of the eyebrows.

• Ekman identified six universal expressions: happiness, anger, sadness, disgust, fear, surprise. • The motion of facial features is also important in conveying emotion.• Animated images are necessary to convey a full range of nuanced emotion; it is especially important to show motion of the eyebrows.

행복함 신남 화남 행복함 신남 화남 슬픔 슬픔

역겨움 결심 두려움 역겨움 결심 두려움 놀람 놀람

INC Lab.

5. Object Display and Object-Based Diagrams5. Object Display and Object-Based Diagrams5. Object Display and Object-Based Diagrams5. Object Display and Object-Based Diagrams

• Wickens (1992) is primarily responsible for the concept of an object display as a graphical device employing “a singlecontoured object” to integrate a largenumber of separate variables.

• Wickens theorized that mapping manydata variables onto a single object willguarantee that these variables areprocessed together, in parallel.

• Among the earlier examples of objectdisplays are Chernoff faces, named aftertheir inventor, Herman Chernoff (1973).

• Faces are probably the most importantclass of objects in the human environment.

• Wickens (1992) is primarily responsible for the concept of an object display as a graphical device employing “a singlecontoured object” to integrate a largenumber of separate variables.

• Wickens theorized that mapping manydata variables onto a single object willguarantee that these variables areprocessed together, in parallel.

• Among the earlier examples of objectdisplays are Chernoff faces, named aftertheir inventor, Herman Chernoff (1973).

• Faces are probably the most importantclass of objects in the human environment.

INC Lab.


• advantages It can reduce accidental misreadings of data values.

• disadvantage They lack generality.

• advantages It can reduce accidental misreadings of data values.

• disadvantage They lack generality.

INC Lab.


• Biederman’s geon theory, outlined earlier, can be applied directly to object display design.

• If cylinders and cones are indeed perceptual primitives, it will make sense to construct diagrams using these geon elements.

• Geons are used to represent the major components of a compound data object, whereas the architecture of the data object is represented by the structural skeleton linking the geons.

• The size of a geon becomes a natural metaphor for the relative importance of a data entity, or its complexity or relative value.

• Biederman’s geon theory, outlined earlier, can be applied directly to object display design.

• If cylinders and cones are indeed perceptual primitives, it will make sense to construct diagrams using these geon elements.

• Geons are used to represent the major components of a compound data object, whereas the architecture of the data object is represented by the structural skeleton linking the geons.

• The size of a geon becomes a natural metaphor for the relative importance of a data entity, or its complexity or relative value.

Geon diagramGeon diagramGeon diagramGeon diagram

INC Lab.


Geon diagramGeon diagramGeon diagramGeon diagram

INC Lab.

6. Perceiving the Surface Shape of Objects6. Perceiving the Surface Shape of Objects6. Perceiving the Surface Shape of Objects6. Perceiving the Surface Shape of Objects

• Use computer graphics techniques to shade the data surface with a simulated light source and give it a simulated color and texture to make it look like a real physical surface.

• Such a simulated surface can be viewed using a stereoscopic viewing apparatus, by creating different perspective images, one for each eye.

• Use computer graphics techniques to shade the data surface with a simulated light source and give it a simulated color and texture to make it look like a real physical surface.

• Such a simulated surface can be viewed using a stereoscopic viewing apparatus, by creating different perspective images, one for each eye.

Spatial Cues for Representing Scalar FieldsSpatial Cues for Representing Scalar FieldsSpatial Cues for Representing Scalar FieldsSpatial Cues for Representing Scalar Fields

INC Lab.

• An important issue in the creation of univariate maps is determining how to represent surface shape most effectively.

• Four principal sets of visual cues for surface shape perception :

1.1. shading modelsshading models2.2. surface texturesurface texture3.3. stereoscopic depthstereoscopic depth4.4. motion parallax.motion parallax.

• An important issue in the creation of univariate maps is determining how to represent surface shape most effectively.

• Four principal sets of visual cues for surface shape perception :

1.1. shading modelsshading models2.2. surface texturesurface texture3.3. stereoscopic depthstereoscopic depth4.4. motion parallax.motion parallax.

Spatial Cues for Representing Scalar FieldsSpatial Cues for Representing Scalar FieldsSpatial Cues for Representing Scalar FieldsSpatial Cues for Representing Scalar Fields


INC Lab.

• The basic shading model used in computer graphics to represent the interaction of light with surfaces has already been discussed in Chapter 2.

• The basic shading model used in computer graphics to represent the interaction of light with surfaces has already been discussed in Chapter 2.

Shading ModelsShading ModelsShading ModelsShading Models

1 Lambertian shading

Light reflected from a surface equally in all directions화소의 밝기 값이 광원과 영상 내 표면의 모양에 의존한다고 가정한다 . 그러나 실제 Lamertian 모델을 따르지 않는 경우가 많아서 이를 개선하기 위한 연구가 많이 이루어지고 있다 .

2 Specular shading

The highlights reflected from a glossy surface

3 Ambient shading

Light coming from the surrounding environment

4 Cast shadows

Shadows cast by an object, either on itself or on other objects ( 일사광선이 불투명한 물체를 통과하지 못하여 생기는 그림자 )


INC Lab.

Shading ModelsShading ModelsShading ModelsShading Models


INC Lab.

Surface TextureSurface TextureSurface TextureSurface Texture

Texture 로부터의 형상화 문제에 대한 첫 번째 시도자는 Gibson [1979] 이었다 . 인간이 어떻게 Texture 로부터 표면 방향을 인지하는가를 이론화시키려 시도를 한 결과 , 그는 Texture 이 표면결소 (texel) 라고 불리는 작은 것으로 이루어진다고 가정하였다 .

Texture 로부터의 형상화 문제에 대한 첫 번째 시도자는 Gibson [1979] 이었다 . 인간이 어떻게 Texture 로부터 표면 방향을 인지하는가를 이론화시키려 시도를 한 결과 , 그는 Texture 이 표면결소 (texel) 라고 불리는 작은 것으로 이루어진다고 가정하였다 .


INC Lab.

관찰자가 대상을 보면서 움직이면 가까운 대상은 먼 대상보다 더 많이 눈의 망막상에서 옮겨지는데 이를 운동시차라 한다 . (motion parallax).

기차를 타고 가다 보면 먼 산은 자기를 따라오고 가까운 전봇대는 빠르게 뒤로 가는 것처럼 보이는 것이 그 예이다 .

움직이는 물체의 경우 그 이동속도는 원근감에 영향을 준다 . 두 점의 깊이를 결정할 때에는 , 그들이 상대적으로 얼마만큼 움직였는가를 관찰한다 . 머리를 왼쪽에서 오른쪽으로 또는 위쪽에서 아래쪽으로 움직이면 가까이 있는 점들이 다른 점들보다 더 많이 움직인 것처럼 보인다 .

이것을 주변시각능력이라고 부른다 . 따라서 머리를 움직이게 되면 장면에 대해 서로 다른 시점들이 생기게 된다 .

관찰자가 대상을 보면서 움직이면 가까운 대상은 먼 대상보다 더 많이 눈의 망막상에서 옮겨지는데 이를 운동시차라 한다 . (motion parallax).

기차를 타고 가다 보면 먼 산은 자기를 따라오고 가까운 전봇대는 빠르게 뒤로 가는 것처럼 보이는 것이 그 예이다 .

움직이는 물체의 경우 그 이동속도는 원근감에 영향을 준다 . 두 점의 깊이를 결정할 때에는 , 그들이 상대적으로 얼마만큼 움직였는가를 관찰한다 . 머리를 왼쪽에서 오른쪽으로 또는 위쪽에서 아래쪽으로 움직이면 가까이 있는 점들이 다른 점들보다 더 많이 움직인 것처럼 보인다 .

이것을 주변시각능력이라고 부른다 . 따라서 머리를 움직이게 되면 장면에 대해 서로 다른 시점들이 생기게 된다 .

motion parallaxmotion parallax motion parallaxmotion parallax


INC Lab.

Integration of Cues Integration of Cues for Surface Shapefor Surface ShapeIntegration of Cues Integration of Cues for Surface Shapefor Surface Shape

Surface 인식에 관해 많은 요인들이 존재하지만 어떤 것이 가장 효과적으로 작용하는가에 관해 실험

-> texture와 shading이 없다면 stereo와 motion은 당연히 효과가 없기 때문에 stereo와 motion의 조합에 대해서 실험

Surface 인식에 관해 많은 요인들이 존재하지만 어떤 것이 가장 효과적으로 작용하는가에 관해 실험

-> texture와 shading이 없다면 stereo와 motion은 당연히 효과가 없기 때문에 stereo와 motion의 조합에 대해서 실험


INC Lab.

each visual task, there is mainly effective factor.


INC Lab.

Interaction of Interaction of Shading and Shading and ContourContour

Interaction of Interaction of Shading and Shading and ContourContour


INC Lab.

Interaction of Shading and ContourInteraction of Shading and Contour Interaction of Shading and ContourInteraction of Shading and Contour


INC Lab.

Bivariate Maps : Lighting and Surface Color Bivariate Maps : Lighting and Surface Color Bivariate Maps : Lighting and Surface Color Bivariate Maps : Lighting and Surface Color


INC Lab.

In this chapter, object 인지를 위해 구조와 표현과 상호작용하는 각기 다른 spatial variables 를 다루는 법을 소개했다 .

However, 뇌가 어떻게 다른 정보들을 구조화하는 지에 대해서는 논의하고 있지 않다 .

Unfortunately, 아직 명확한 답은 없다 . 매우 추론적인 이론만이 존재한다 .

In this chapter, object 인지를 위해 구조와 표현과 상호작용하는 각기 다른 spatial variables 를 다루는 법을 소개했다 .

However, 뇌가 어떻게 다른 정보들을 구조화하는 지에 대해서는 논의하고 있지 않다 .

Unfortunately, 아직 명확한 답은 없다 . 매우 추론적인 이론만이 존재한다 .

7.Integration7.Integration7.Integration7.Integration

Thank you!!Thank you!!Thank you!!Thank you!!

chapter 7. visual objects and data objects 컴퓨터 교육학과 박사과정 차승은 2007. 05....

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