This document discusses a proposed technique for secure data transmission that combines digital image watermarking and image compression. It begins with background information on digital watermarking, including its classifications, requirements, general system, and techniques such as spatial domain and frequency domain methods. It then provides an overview of image compression, including its benefits, techniques such as lossless and lossy compression, and common compression methods. The proposed technique embeds a watermark into an image using discrete cosine transform (DCT) based watermarking in the frequency domain. It then applies lossy image compression to the watermarked image using an improved adaptive Huffman coding algorithm. The goal is to achieve higher security for data transmission by combining these two techniques compared to