Table 7 List of evaluation metrics used in review papers.
Evaluation metric | Abbreviation | Definition |
|---|---|---|
Entropy | ENT | The amount of energy is not available for the system to perform any fruitful work. In other words, it refers to the disorder of the system |
Histogram | HIS | It is a powerful statistical method to poetry the numerical data in the form of a bar chart representing segmented data on one axis and time interval on another |
Correlation coefficient | CC | It determines the relationship between two variables in terms of its direct/indirect and weak/intermediate and strong |
Variance | VAR | It is used to show the variability in data for standardized values such as the mean. In other words, it shows the spread of data over given intervals |
Peak signal-to-noise ratio | PSNR | It is used as a quality measure to show the comparison of quality between original and compressed images with the help of PSNR |
Number of pixels change rate | NPCR | It represents the rate of the number of pixels that have changed in the original image and cipher image |
Unified average changing intensity | UACI | It determines the difference in color intensities between two images |
Accuracy | ACC | It is the measure of the closeness of the obtained result with a particular value |
Sensitivity | SEN | It refers to the proportion of those values that satisfy the true condition when tested for positive results |
Encryption time | ET | The time utilized to perform encryption |
Decryption time | DT | The time taken to decrypt back is DT |
Mean square error | MSE | It is determined by taking the average of differences between actual and estimated values |
Keyspace | KS | In cryptography, this term is taken as the sample space of all possible sets that could be used to start up the algorithm deployed in cryptanalysis |
Mean absolute error | MAE | It takes the average value of the error in an experiment regardless of the direction of the error. It is computed by taking the average differences between predicted and observed values |
Key reconstruction rate | KRR | This is the rate at which the secret key is re-created for the algorithm in use at a given period |
