Discrete Cosine Transform Method for Watermarking in Digital Image Processing
Nur Lukman, Jumadi Jumadi, Muhammad Faris Aminuddin, Dian Sa’adillah Maylawati, Nunik Destria Arianti, Muhammad Ali Ramdhani · 2021
Today, image data is part of the development of big data whose volume, variety, and velocity are huge. The watermarking process is one of the simplest methods but effective and popular methods to protect copyright from images and insert other important information in an image. This study aims to carry out a watermarking process on an image by inserting another image. The method used is Discrete Cosine Transform (DCT) in the process of watermarking images. This research conducted 20 experiments for the image watermarking process with a combination of existing image data. The results of the experiment show that all of the image objects carried out by the watermarking process using DCT were successfully carried out with an accuracy value is 100%. However, the process of decryption or image separation after watermarking was not successful. In the image decryption (or image restoration) experiment using DCT, nothing works because the original image inserted by another image does not return to its original state. This result shows that DCT is only good to use during the watermarking process.