Compute risks characterizing the quality of smoothing results

Methods function risk in package aws. For an given array u the following statistics are computed : Root Mean Squared Error RMSE <- sqrt(mean((y-u)^2)), Signal to Noise Ratio SNR <- 10*log(mean(u^2)/MSE,10), Peak Signal to Noise Ratio PSNR <- 10*log(max(u^2)/MSE,10), Mean Absolute Error MAE <- mean(abs(y-u)), Maximal Absolute Error MaxAE <- max(abs(y-u)), Universal Image Quality Index (UIQI) (Wang and Bovik (2002)).

# S4 method for array
risk(y, u=0)
  # S4 method for aws
risk(y, u=0)
  # S4 method for awssegment
risk(y, u=0)
  # S4 method for ICIsmooth
risk(y, u=0)
  # S4 method for kernsm
risk(y, u=0)
  # S4 method for numeric
risk(y, u=0)

Arguments

y	object
u	array of dimension dim(y) or dim(extract(y,what="yhat")$y) or scalar value used in comparisons.

Methods

signature(y = "ANY")

The method extract and/or compute specified statistics from object of class

signature(y = "array")

Returns a list with components RMSE, SNR, PSNR, MAE, MaxAE, UIQI

signature(y = "aws")

Returns a list with components RMSE, SNR, PSNR, MAE, MaxAE, UIQI

signature(y = "awssegment")

Returns a list with components RMSE, SNR, PSNR, MAE, MaxAE, UIQI

signature(y = "ICIsmooth")

Returns a list with components RMSE, SNR, PSNR, MAE, MaxAE, UIQI

signature(y = "kernsm")

Returns a list with components RMSE, SNR, PSNR, MAE, MaxAE, UIQI

signature(y = "numeric")

Returns a list with components RMSE, SNR, PSNR, MAE, MaxAE, UIQI

Author

Joerg Polzehl polzehl@wias-berlin.de

References

V. Katkovnik, K. Egiazarian and J. Astola, Local Approximation Techniques in Signal And Image Processing, SPIE Society of Photo-Optical Instrumentation Engin., 2006, PM157

Z. Wang and A. C. Bovik, A universal image quality index, IEEE Signal Processing Letters, vol. 9, N3, pp. 81-84, 2002.