Transcript Shot boundary detection based on frame histograms analysis

Shot boundary detection based on
frame histograms analysis
Tomsk Polytechnic University
Vakulenko M.D.1, Kovalenko D.A. 2, Tolkunov S.V.2,
Master Students Gr.1 -8BM10, 2 -8VM13
Scientific advisor: Dr. Sergey V. Axyonov
Shot boundary detection based on frame
histograms analysis
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Motivation, Targets and Tasks
Motivation
 Presence of huge unstructured and unindexed video archives in the world
 Video scenes search problem
 Need for automated video content analysis
Target
Automated scenes splitting by the shot boundary detection based on histograms
difference analysis
Tasks
 Create and implement an algorithm that is capable of detection base cuts in the
movies based on hard threshold.
 Create and implement an algorithm that is capable of detection base cuts in the
movies based on adaptive threshold.
 Estimate the effectiveness of the best developed algorithm for some different
movies (quality, sizes).
Shot boundary detection based on frame
histograms analysis
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Application
Shot boundary detection based on frame
histograms analysis
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Different Cuts
Shot boundary detection based on frame
histograms analysis
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Overview of the Model
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histograms analysis
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Mathematical Model
Elements of analyzed vector:
- correlation function
, ,
- vectors obtained from histograms of red, green and blue component of the i-th frame
According to obtained vector C adaptive threshold can be calculated in
following form:
- threshold value
- weighting factor
- mathematical expectation
n – number of neighbor of analyzed element
- variance
Video segmentation
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Algorithm
cvCreateFileCapture
While(!EOF)
{
cvQueryFrame
cvCalcHist
cvCompareHist
}
• Get frames with some step from video file
• Calculate histogram difference between
neighboring frames
• Store it in the array
• Calculate adaptive threshold
• Peaks which we received are places of cuts
cvAdaptiveThreshold
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histograms analysis
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Examples
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histograms analysis
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Results
Developed needed mathematical model for movie shot
boundary detection.
Created a C++ program that implements the model based on
the OpenCV library.
The software was tested to detect shot boundary for the
different media types (different movie quality, different cut
types).
The system can detect about 90% described cuts in the
movies.
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histograms analysis
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