Theme 3: Research and theory ( before seminar )

Summary of the journal : Journal of Visual Communication and Image Representation on A survey of human pose estimation: The body parts parsing based methods 

(link to paper: http://www.sciencedirect.com/science/article/pii/S1047320315001121)

In this paper they aim to study human movement and pose to solve the computer’s vision in human pose estimation. They see that in previous studies still lack a survey to summarize the most recent progress on body pose estimation. They present a general framework of human pose estimation and go through latest technical progress and discuss the limitations.

Human pose estimation (HPE) usually need extra hardware device to capture human pose and construct a human skeleton based on the capture body joints. There are many new applications using HPE along with their technological devices eg. In sport scene, with the use of HPE they track athletes activities and location. HPE is important computer vision problem and playing important role of real-world applications. 

In order to learn human pose and action/activity recognition there are many tool used in development of HPE field. For instance, the model based methods, especially the pictorial structure model.  They categorized the study into two stages: 1)preprocessing and 2) body parts parsing. They summarized the whole process of the common human pose estimation. The preprocessing stage includes feature extraction, camera calibration, body detection and foreground segmentation. According to this framework, this survey is organized as follows. 1) to investigates the related studies on preprocessing for HPE. 2) to gives a comprehensive review on body parts parsing, which is the most important stage in HPE. Various datasets and evaluation methodologies for HPE are discussed. Finally, they concludes this survey and foresee the future directions for HPE study.

1) Briefly explain to a first year university student what theory is, and what theory is not.

Theory can mean different things in different field. Theory in music and technology is developed and used in different ways. There is a concern on theory for the information system (IS) field because the characteristic of the field concerned both people and artifacts or tools that are made by human conception in human-machine system. Theory in IS is to provide analysis, explanation, prediction and prescription. Theory can fall into five different types which are labeled: (1) theory for analyzing, (2) theory for explaining, (3) theory for predicting, (4) theory for explaining and predicting (EP theory), and (5) theory for design and action. [1]

In Dictionary theory generally means a ‘principle that explain a group of facts or phenomenal’ or ‘a hypothesis that has been confirmed or established by observation or experiment’ a ‘method of doing thing aim to describe, explain, and enhance understanding of the world’ and many more definitions. From philosophers of science, theory means a testable providing explanations and predictions. In some field, Theory must meet some primary criteria such as  (1) constructs must be identified; (2) relation- ships among these constructs must be specified; and (3) these relationships must be falsifiable (that is, able to be tested). [1]

However in the field of technological artifacts, the problem of theory conducted is concerns to be empirical theory.  As Herbert Simon mentioned in The Sciences of the Artificial (1996)   “I thought I began to see in the problem of artificiality an explanation of the difficulty that has been experienced in filling engineering and other professions with empirical and theoretical substance distinct from the substance of their supporting sciences.” the primary goal is to develop theory that is testable NOT in a narrow sense but seek for validity and credibility. Theory has an existence separated from the subjective view of individual researchers. 

Facts, or knowledge of an individual fact or event are not theory. Though Abstraction and generalization about phenomenon, interactions, and causation are not theory, we might need generalization and abstraction to predict, provide, and develop a way to think of other theory.

2) Describe the major theory or theories that are used in your selected paper. Which theory type (see Table 2 in Gregor) can the theory or theories be characterized as?

The paper “A survey of human pose estimation: The body parts parsing based methods” falls into  Theory for Analyzing category because its purpose is to explain  the generalization of human movements by analysing various detecting program. They try to explain recent technology way to capture the dimensions of human activities by observing through the model base method and pictorial structure and summarise what they found in the survey. They look into the recent studies about technology of human movement and computer sensor capture each pose from the 2D or 3D human body part positions from still images or videos. they found pros and cons and what perform best for each technology and conclude its difficulties.

3) Which are the benefits and limitations of using the selected theory or theories?

This theory type gives out the importance of systematics pre-study leading to other good scientific method. This type of theory helps providing clear outline of the information to be studied further.

This type of theory that describes and analyses is valuable, because in the new technology field it might be so little is known about. However information gathered would be expected to have credibility and the important categories or elements should not be omitted. 

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source: 1. http://heim.ifi.uio.no/%7Epetterog/Kurs/INF5220/NatureofTheoryMISQ.pdf