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Q a) CUT GRAD CUT. Objective: Rough Indexing: Real Time Shot Boundary Detection Rough Datas – Rough Solution Fast & Intelligent Browsing TRECVid Shot Change Transition Effects Classification. Context: MPEG Video Files (6h for SBD task) Rough Data Extraction:
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Q a) CUTGRADCUT • Objective: • Rough Indexing: • Real Time Shot Boundary Detection • Rough Datas – Rough Solution • Fast & Intelligent Browsing • TRECVid • Shot Change Transition Effects Classification • Context: • MPEG Video Files (6h for SBD task) • Rough Data Extraction: • Motion compensation vectors • DC Coefficients (I-Frames or Prediction Error) • Intracoded/outliers MB Map Robust Camera Motion Estimation: 6 parameters affine model robust estimator DeltaQ b) Frame Dissimilarity Measures: P-Frames MC: Motion Continuity Measure Q: Number of Intracoded Macroblock ∆Q: Derivative of Q D: P-Frames Dissimilarity Measure (#) SHOT BOUNDARY DETECTION IN THE FRAMEWORK OF ROUGH INDEXING PARADIGM AUTHORS: L. Primaux {primaux@labri.fr}; J. Benois-Pineau {jenny.benois@labri.fr}; P. Krämer {kraemer@labri.fr}; J-P Domenger {domenger@labri.fr} LaBRI CNRS UMR 5800 / University Bordeaux1 http://www.labri.fr/Recherche/ImageSon/AIV/ I-Frames DC I-Frames matching takes into account Luminance and chrominance WMSE: I-Frames Dissimilarity Measure Weighted MSE Transition Effects Classification: The classification consists in considering as “CUT” all peaks which are immediately followed by their opposite, with the tolerance of one I-Frame in between. Moreover the peak must not be preceded by a high positive value. Otherwise peaks are considered as “GRAD”. The decision based on the derivative of the number of intra-coded macroblocks showed an increased performance of 20% in recall compared to absolute value Q in (#). Shot Boundary Detection: We assume a Gaussian Distribution of D, which is online updated as follows: Detection threshold λ (Kp set to1.8): here in order to let Gaussian more reactive, and α is set to 0,15 Results: The most equilibrated result is a recall of 70.2% and a precision of 63.4%. The best precision is 73% for a recall of 65% and the best recall is 74% for a precision of 57%. run-sec decod-sec segm-sec processor-type-and-speed 6732 3874 2858 Pentium 4 2.8GHz The index i is retained as shot border if: But still, to recognize D(i) as a shot change peak, we consider the previous shot change peak value D(j) and apply the following decision rule: