Analysis of Cryptography before Steganography Operation by ROC Curves and Confusion Matrices Criteria

The steganography algorithms based on media type, format and capacity are used for different applications. The use of cryptographic algorithms also depends on the type of application. The challenge that can be investigated is the use of cryptographic algorithms in the steganography process, which must be properly scrutinized due to the special sensitivities of these two technologies. The use of cryptographic algorithms in steganographic systems increases the security of hidden data, but this security level should not make the entropy more visible and did not consider other metric. For this reason, in this paper, two steganographic algorithms for JPEG image and two steganographic algorithms for audio in WAV format are investigated, so that before the steganographic operation, a cryptography algorithm is used to encrypt the message. In the following, after reviewing the steganographic algorithms using several valid steganalysis, the advantages of using and not using these cryptographic algorithms against their disadvantages are reviewed and suggestions about their use in steganography algorithms and systems are presented.