Cheating identifiable polynomial based secret sharing scheme for audio and image

Polynomial based secret sharing is the art of protecting information and a tool used in areas where a secret has to be distributed among multiple parties. In this method, secret is encrypted into noisy shares and transferred to participants in the group. Decoding of secret is possible only when sufficient number of authorized members in the group, stack their respective shares. In this article, polynomial based secret sharing for audio is proposed that computes a checksum to identify the dishonest participant and also the audio shares generated are of smaller dimension. To achieve this, a polynomial function is defined by considering amplitude values and random values as coefficients. Inclusion of random value as the coefficient of higher degree term in the polynomial makes the audio shares noisy and does not provide any information about the secret. This reduces the overhead of performing preprocessing on original audio before shares are generated. In addition, our proposed method can be used for multi secret sharing. Proposed scheme also facilitates identification of dishonest participant before reconstruction of secret through a trusted entity called combiner.