Exploring recent advances in random grid visual cryptography algorithms

Visual cryptography scheme is initiated to securely encode a secret image into multiple shares. The secret can be reconstructed by overlaying the shares, making it perceptible to the human visual system. Random grid visual cryptography offers key advantages over traditional visual cryptography such as avoiding pixel expansion and the requirement for intricate codebook design. This paper is intended to conduct a critical analysis and implementation of various algorithms in random grid visual cryptography from 2011 to 2022. The focal parameters of this study are theoretical contrast, experimental contrast and visual quality. Experiments were done on binary images for (k, n) algorithms considering different values of threshold. By implementing and analysing the results, the scheme which gives the optimal result is identified.