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Table 1 Lossless compression results

From: Compression of high-density EMG signals for trapezius and gastrocnemius muscles

Method Signal Arrangement Muscle % of MVC
     20% 40% 60% 80%
ZIP S k L UT 17.98 ± 0.59 14.69 ± 0.66   
ZIP S k T UT 19.78 ± 0.51 16.69 ± 0.67   
JPEG S k L UT 36.72 ± 0.77 31.79 ± 0.79   
JPEG S k T UT 36.74 ± 0.77 31.81 ± 0.78   
JPEG Δ k L UT 40.86 ± 0.31 38.13 ± 0.40   
JPEG Δ k T UT 40.88 ± 0.31 38.15 ± 0.41   
ZIP S k L MG 37.32 ± 0.89 31.73 ± 0.56 27.32 ± 0.63 25.31 ± 0.66
ZIP S k T MG 38.11 ± 0.82 32.94 ± 0.50 28.71 ± 0.59 26.78 ± 0.65
JPEG S k L MG 59.29 ± 1.21 52.52 ± 0.68 47.77 ± 0.59 45.40 ± 0.76
JPEG S k T MG 59.30 ± 1.20 52.53 ± 0.69 47.79 ± 0.59 45.41 ± 0.77
JPEG Δ k L MG 58.31 ± 0.72 53.40 ± 0.53 49.88 ± 0.55 48.21 ± 0.67
JPEG Δ k T MG 58.31 ± 0.72 53.41 ± 0.53 49.90 ± 0.55 48.22 ± 0.67
  1. Lossless compression of single-differential (S k ) signals and their differences in time (Δ k ). Mean values ± standard deviation of file-size reduction (%) were computed for 40 epochs per contraction level (% of MVC) of upper trapezius (UT) signals and for 8 epochs per contraction level (% of MVC) of medial gastrocnemius (MG) signals. Arrangements were longitudinal (L) and transversal (T). Methods were ZIP and lossless JPEG.