Abstract:
In this thesis, we ropose an advanced multi-evel image steanography system that cmbines zlib compresson, hybrid AES-56-Blowfish encyption, and LSB mbedding for better ecurity and image quality in secret commuication. We proose integrating key innovationsthat also relieve some of the critical limiations of curren steganographic methds: 1) Maxium Zlib Compression using the LZ7 algorithm for efficiency2) Upgraded AS-256-GCM replacng the conventinal AES-128 for direct ut ore secure encryption 3) Hybrid ES-Blowfish encyption architecure providing multi-layered efense with authenticationcapabilities. An imagedependent key erivation using imageindependent RGB histogram analyss with PBKDF2 algorithm construct unique and rliably strong encryption keys for every coer image. This methodoogy comprises four ke steps, the first of which is a lossy copression of the message with the lvel 9 in zlib algrithm, then a double layer-enrypting with both AS-256- GCM and Blwfish-ECB andPKCS7 pdding, followed by step-ise Least Significant Bit (LSB) steganography embeddng into the RGB cannels, as well as an i-depth quaity assessment using Peak Signal-to-Noie Ratio (PSR) and Mean Square rror (MSE) metrics. e perform the experimental validation o some standard testimages such as te Lena and Baboon images to show that our method givs superior performace with the Peak Signal-o-Noise Ratio (PSNR) of the restored imag as high as 80.0 dB and 76.17 dB resectively, with spatial reresentation with minimal visual distortion ad maintaining the qality of images. Our itegrated compression provides a data reduction of up t 39.29% while eficiently keeping he encryption tie under 0.11 seconds. A comparion demonstrtes that the qualty of ourconstruction povides signiicant advantages over existing mplementations: ES-256 vs. AES-128 pgrae results in mproved security; additional compression results in effiiency improvements; and GCM moe tamper etection provides authenticated ncryptionwhile improving encryptio fficiency as well. Interestingly, this research improvs cybersecurity to find high security, thebest image quality, and processing efficiency throug simultaneos multi-level steganography. The proposed system holds great promise for secure communicaton applicationsin military, medical, and digital rights management area and sets new performance standards for image-based covert commuication systems by emplying software engineering approaches
