In the digital age, securing image data has become paramount due to the increasing prevalence of image exchange across digital platforms. Traditional methods, such as visual cryptography, offer certain security benefits but come with limitations such as image quality loss and high storage requirements. This paper introduces a novel image encryption scheme that combines block permutation and modular arithmetic shuffling to enhance security while maintaining low computational complexity. The method first standardizes image dimensions, divides the image into non-overlapping square blocks, and applies independent row and column permutations within each block. Subsequently, a modular arithmetic-based shuffling technique is employed using a coprime parameter, ensuring a secure and reversible encryption process. To strengthen diffusion and improve resistance to statistical attacks, an XOR operation is performed using a cryptographically secure key stream generated via AES in counter mode (AES-CTR) with a secret key. The complete scheme operates with a time complexity of O(m1 n1), where m1 and n1 are the image dimensions. Experimental results confirm the method’s robustness and suitability for secure image transmission and storage.