Secured steganographic scheme for highly compressed color image using weighted matrix through DCT

Abstract

Due to the rapid growth of internet technology and the advent of various image processing tools, people started using digital media for hidden communication to protect valuable information which is important for multimedia commercials, health-care, medical and defense applications. On the other hand, image authentication and tamper detection are essential, especially when it is utilized for evidence of legal action. In this paper, a weighted matrix based steganographic scheme has been designed for highly compressed (Quality Factor (QF) 40) color image through discrete cosine transform (DCT) to maintain a good balance between payload and imperceptibility. Here, the AC components are collected from $(8\times 8)$ quantized DCT coefficient matrices of YCbCr channel. Then, a series of $(3\times 3)$ original matrices are formed to hide secret data. The collection of AC components is controlled by 128 bits shared secret key. A predetermined weighted matrix is employed to select the embedding position within a $(3\times 3)$ coefficient matrix of a cover image through the sum of the entry-wise multiplication operation. The proposed scheme provides good embedding capacity with the high visual quality compared to existing state-of-the-art methods. Finally, different steganographic analysis and attacks are carried out to observe its imperceptibility and robustness.

Keywords:

• Steganography
• weighted matrix
• quantized DCT coefficient
• PSNR
• RS-analysis

Disclosure statement

No potential conflict of interest was reported by the authors.