Biblio
Information security is crucial to data storage and transmission, which is necessary to protect information under various hostile environments. Cryptography serves as a major element to ensure confidentiality in both communication and information technology, where the encryption and decryption schemes are implemented to scramble the pure plaintext and descramble the secret ciphertext using security keys. There are two dominating types of encryption schemes: deterministic encryption and chaotic encryption. Encryption and decryption can be conducted in either spatial domain or frequency domain. To ensure secure transmission of digital information, comparisons on merits and drawbacks of two practical encryption schemes are conducted, where case studies on the true color digital image encryption are presented. Both deterministic encryption in spatial domain and chaotic encryption in frequency domain are analyzed in context, as well as the information integrity after decryption.