C-HIDE: A Steganographic Framework for Robust Data Hiding and Advanced Security Using Coverless Hybrid Image Encryption With AES and ECC

Coverless image steganography conceals information without modifying the carrier image, addressing vulnerabilities in traditional methods. However, existing approaches often require transmitting metadata, raising suspicion and security risks. To overcome these limitations, we propose Coverless Hybrid Image Data Encryption (C-HIDE), a robust steganographic method integrating Advanced Encryption Standard (AES) for data confidentiality and Elliptic Curve Cryptography (ECC) for secure key exchange. The system ensures secure transmission without altering cover images, making embedded data harder to detect. C-HIDE eliminates metadata transmission by enabling both sender and receiver to independently generate synchronized coverless image datasets (CIDs) using random seeds. Encrypted secret data is mapped to images whose hash sequences correspond to segments of the message, with Speeded-Up Robust Features (SURF) ensuring reliable image matching. At the receiver’s end, ECC-decrypted AES keys recover the original message while SURF retrieves relevant images. Experimental results demonstrate that C-HIDE achieves an embedding capacity of 574 bits per image, significantly surpassing DCT (256 bits) and DWT (128 bits) techniques. The system maintains 98.5% accuracy under attacks such as noise addition, cropping, and geometric transformations. Furthermore, it enhances security by eliminating metadata transmission, achieving a zero additional information ratio, unlike conventional methods requiring up to 25% extra data. By integrating encryption, minimizing detection, and removing metadata transmission, C-HIDE provides a secure, efficient, and scalable solution for covert communication in real-world applications.