Automated%20Shot%20Boundary%20Detection%20in%20VIRS

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Automated Shot Boundary Detection in VIRS

• DJ Park
• Computer Science Department
• The University of Iowa

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Introduction

• VIRS?
• Visual Information Retrieval System
• Works on multimedia information domain such as
  video, sound, etc
• Aims for content-based analysis, retrieval and
  presentation
• Find all videos that Iowa football team plays

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Building VIRS

• Shot Boundary Detection
• Scene Boundary Detection
• Key Frame Generation
• Pattern Recognition
• Indexing with Meta Data
• Interface and Querying Method

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Shot Boundary Detection

• A sequence of frames captured by a single camera
  in a single continuous action
• Most basic unit of video data
• A scene is a logical group of shots into a
  semantic unit
• Many different styles and techniques ( cut, fade,
  wipe, dissolve )
• How to detect among these styles?
• What about camera/object movements?

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General Approach

• Frame to Frame Comparison
• Take 2 subsequent frames and measure their
  differences
• How to define these differences discriminates
  each method
• Pixel Difference
• Color Histogram Difference
• Edge Difference

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Pixel Difference

• One of the earliest methods
• How many pixels are different between subsequent
  frames?
• Problems?
• Improvement using blocks instead of pixels

(X,Y)
(X,Y)
Frame t1
Frame t
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Color Histogram Difference

• Much more accurate than simple pixel-wise
  approach
• Compare the number of occurrences for each color
  between subsequent frames
• Problems?

Frame t
Histogram t
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Edge Difference

• No color information is needed
• Compare entering edge pixels and exiting edge
  pixels
• Better than other methods in detecting fade,
  wipe, dissolve
• Problems?

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Future Works

• Evaluation and Combination of existing methods
• Relating shot boundary information with scene
  boundary how to group shots into semantic unit?
• Using sound information for shot ( or scene )
  boundary detection?
• Using object-oriented approach or 3-D image
  modeling technique?

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Questions?