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Computer Vision Tutorial

basic introduction

Liyuan Cao Haidong Gu

Industrial and Systems Engineering

Lehigh University

OptML, Sep 4, 2019

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Table of Contents

1 What is Computer Vision?

2 Related Fields of Computer Vision

3 Computer Vision Applications

4 Three-Level Paradigm

5 Types of CV Problems

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Table of Contents

1 What is Computer Vision?

2 Related Fields of Computer Vision

3 Computer Vision Applications

4 Three-Level Paradigm

5 Types of CV Problems

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What is Computer Vision?

Objective of Computer Vision

The objective of computer vision is to make computers see and interpret the world likehumans and possibly even better than us.

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What is Computer Vision?

Human vision performs multiple visual tasks quite e↵ortlessly and e↵ectively.

How is visual information processed and understood in biological systems?

What is the nature of computation involved in visual tasks?

How might we build machines that can see?

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What is Computer Vision?

Figure: Ball Catch

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What is Computer Vision?

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What is Computer Vision?

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What is Computer Vision?

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What is Computer Vision?

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What is Computer Vision?

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What is Computer Vision?

Recreating human vision isn’t just a hard problem, it’s a set of them, each of which relieson the other.

Definition of Computer Vision

Computer Vision is concerned with the automatic extraction, analysis and understandingof useful information from a single image or a sequence of images.

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What is Computer Vision?

Computer Vision

theoretical and algorithmic basis toachieve automatic visual understanding

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What is Computer Vision?

Computer Vision

high-level understanding fromdigital images or videos

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What is Computer Vision?

From the biological science point of view,

Computer Vision

computer vision aims to come up withcomputational models for human

visual system

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What is Computer Vision?

From the engineering point of view,

Computer Vision

computer vision aims to build autonomoussystems to perform some of the tasks which

the human visual system can performand even surpass it in many cases.

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What is Computer Vision?

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What is Computer Vision?

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What is Computer Vision?

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What is Computer Vision?

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What is Computer Vision?

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What is Computer Vision?

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What is Computer Vision?

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Table of Contents

1 What is Computer Vision?

2 Related Fields of Computer Vision

3 Computer Vision Applications

4 Three-Level Paradigm

5 Types of CV Problems

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Related Fields of Computer Vision

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What is Computer Vision?

Computer Vision

can be studied from a purely mathematical point of view

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Related Fields of Computer Vision

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Related Fields of Computer Vision

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Related Fields of Computer Vision

Computer vision systems rely on image processing techniques to pre-process the imagedata for robust high-level analysis.

Digital Image Processing

image compression

image restoration

image enhancement

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Related Fields of Computer Vision

The robust high-level analysis is the next major task in computer vision pipeline. It is thearea where neuroscience plays an important role. Specifically, the study of the biologicalvision system.

Neuroscience

(a) eye (b) neuron (c) brain structure

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Related Fields of Computer Vision

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Table of Contents

1 What is Computer Vision?

2 Related Fields of Computer Vision

3 Computer Vision Applications

4 Three-Level Paradigm

5 Types of CV Problems

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Computer Vision Applications

Computer vision is transitioning from a nascent

stage and is proving to be incredibly useful in

several application areas.

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Computer Vision Applications

Computer Vision for Security

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Computer Vision Applications

Figure: visual surveillance

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Computer Vision Applications

Figure: fingerprint-based identification and authentication

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Computer Vision Applications

Figure: iris identification and authentication

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Computer Vision Applications

Figure: face recognition

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Computer Vision Applications

Computer Vision in

Multimedia and Entertainment

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Computer Vision Applications

Figure: face recognition

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Computer Vision Applications

Figure: augmented reality game

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Computer Vision Applications

Computer Vision for Navigation

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Computer Vision Applications

Figure: robot navigation

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Computer Vision Applications

Figure: autonomous driving

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Computer Vision Applications

Computer Vision in Retail

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Computer Vision Applications

Figure: automated supermarket

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Computer Vision Applications

Figure: visual search on smartphone cameras

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Computer Vision Applications

Computer Vision in Industry

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Computer Vision Applications

Figure: real-time box analytics

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Computer Vision Applications

Figure: auto cycle counting

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Computer Vision Applications

Figure: inspect products

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Computer Vision Applications

Computer Vision for Social Causes

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Computer Vision Applications

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Table of Contents

1 What is Computer Vision?

2 Related Fields of Computer Vision

3 Computer Vision Applications

4 Three-Level Paradigm

5 Types of CV Problems

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Three-Level Paradigm

Computer vision conceptscan be broadly categorized as

low, mid and high level vision techniques

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Three-Level Paradigm

Low Level Vision

image processing techniques, feature detection andmatching and early segmentation

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Three-Level Paradigm

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Three-Level Paradigm

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Three-Level Paradigm

Mid Level Vision

image segmentation, things start to come togetherattributing meaning

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Three-Level Paradigm

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Three-Level Paradigm

High Level Vision

Visual recognition and scene understanding,algorithms which makes sense of the visualcontent and make computer vision live up

to the capabilities of human vision

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Three-Level Paradigm

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Three-Level Paradigm

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Three-Level Paradigm

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Three-Level Paradigm

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Three-Level Paradigm

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Three-Level Paradigm

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Table of Contents

1 What is Computer Vision?

2 Related Fields of Computer Vision

3 Computer Vision Applications

4 Three-Level Paradigm

5 Types of CV Problems

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Types of CV Problems

Recognition determining whether or not the image data contains some specific object,feature, or activity

Motion Analysis an image sequence is processed to produce an estimate of the velocityeither at each points in the image or in the 3D scene, or even of thecamera that produces the images

Scene Reconstruction computing a 3D model of the scene

Image Restoration The aim of image restoration is the removal of noise (sensor noise,motion blur, etc.) from images.

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Recognition: Object Recognition, Identification, Detection

Figure: Object Recognition: one or several pre-specified or learned objects or object classes can

be recognized, usually together with their 2D positions in the image or 3D poses in the scene

Figure: Identification: an individual instance of an object is recognized

Detection: the image data are scanned for a specific condition.Lehigh ISE OptML Sep 4, 2019 70 / 74

Motion Analysis: Egomotion, Tracking, Optical flow

Figure: Egomotion: determining the 3D rigid motion (rotation and translation) of the camera

from an image sequence produced by the camera. (visual odometry)

Figure: Tracking: following the movements of a (usually) smaller set of interest points or objects

(e.g., vehicles, humans or other organisms) in the image sequence.

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Motion Analysis: Egomotion, Tracking, Optical flow

Figure: Optical Flow: to determine, for each point in the image, how that point is moving

relative to the image plane, i.e., its apparent motion. This motion is a result both of how the

corresponding 3D point is moving in the scene and how the camera is moving relative to the

scene.

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Scene Reconstruction

Figure: Scene Reconstruction: Given one or (typically) more images of a scene, or a video, scene

reconstruction aims at computing a 3D model of the scene.

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Image Restoration

(a) inpainting

Figure: Image Restoration

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