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Table 1 Absolute error in estimating modulus and phase of the flow

From: Short range tracking of rainy clouds by multi-image flow processing of X-band radar data

Simulation parameters Lucas-Kanede approach Horn-Schunck approach
  Modulus (px/ΔT) Angle (°) Modulus (px/ΔT) Angle (°)
  F No F F No F F No F F No F
N = 4, SNR = 10 dB 0.58 ± 0.62 0.49 ± 0.54 1.0 ± 1.7 0.6 ± 0.7 0.50 ± 0.59 0.41 ± 0.42 2.3 ± 2.0 2.2 ± 1.7
N = 4, SNR = 20 dB 0.58 ± 0.60 0.49 ± 0.53 0.9 ± 1.8 0.5 ± 1.7 0.49 ± 0.57 0.39 ± 0.40 1.8 ± 1.9 1.7 ± 1.5
N = 10, SNR = 10 dB 0.06 ± 0.03 0.04 ± 0.04 0.2 ± 0.2 0.2 ± 0.2 0.06 ± 0.03 0.07 ± 0.08 2.4 ± 3.3 1.7 ± 1.9
N = 10, SNR = 20 dB 0.05 ± 0.04 0.04 ± 0.03 0.2 ± 0.2 0.2 ± 0.2 0.06 ± 0.03 0.07 ± 0.08 0.7 ± 0.6 0.7 ± 0.5
  1. Notes: The same data as in Figure 3 were used. Different methods (Lucas-Kanede or Horn-Schunck approach, including the production term [F] or estimating only the flow [No F]), eight values of modulus and nine values of phase of the simulated flow, different numbers N of frames, additive Gaussian noise with different SNR (ten realizations for each simulation) are considered. The errors are given in terms of mean ± standard deviation, approximated to the second digit for the modulus and to the first digit for the phase. Modulus is indicated in pixel (px) per sampling period (ΔT). Angles are indicated in(°).