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Variable Metric For Binary Vector Quantization. Ismo Kärkkäinen and Pasi Fränti. UNIVERSITY OF JOENSUU DEPARTMENT OF COMPUTER SCIENCE JOENSUU, FINLAND. Distance and distortion functions. Distance function:. Distortion function:. Distortion for binary data.
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Variable Metric For Binary Vector Quantization Ismo Kärkkäinen and Pasi Fränti UNIVERSITY OF JOENSUU DEPARTMENT OF COMPUTER SCIENCE JOENSUU, FINLAND
Distance and distortion functions Distance function: Distortion function:
Distortion for binary data Internal distortion for one variable: qjk = the number of zeroes rjk = the number of ones Cjk = the current centroid value for variable k of group j.
Optimal centroid position Optimal centroid position depends on the metric. Given: The optimal position is:
Test images Blockwise quantization of pixels into two levels according to the mean value of the 4x4 blocks. 44 pixel blocks.