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The Implememtation Of Hiding Information By Using Discrete Wavelet Transform (DWT)

Devi Silvia Simbolon — 2024-12-18

Steganography using Discrete Wavelet Transform (DWT) is a technique for embedding information into an image without significantly altering its visual quality. This study aims to analyze the effectiveness of DWT in securing hidden messages within digital images. DWT decomposes image signals into approximation and detail coefficients, allowing data embedding in the high-frequency components while preserving the most essential image features. The research methodology involves converting secret messages into numerical form, applying DWT to the image, embedding data into the detail coefficients, and reconstructing the image using inverse DWT. The results show that this approach enables secure and imperceptible data hiding while maintaining image quality. Additionally, DWT provides advantages in signal analysis, data compression, and noise resistance, making it a robust technique for steganography. The study concludes that DWT is an effective method for secure data embedding with minimal distortion, offering potential applications in digital watermarking and confidential communication.

Steganography With End Of File

Zuvernius Sitohang — 2024-12-25

Steganography is the science and art of hiding secret messages in other messages, so that the existence of the message cannot be known by third parties. One method used in steganography is the EOF (End of File) message insertion method, which is inserting data at the end of a file by providing a special mark to identify the beginning and end of the data. This technique is used to insert data as needed, and the steganographed file does not appear to change visually or audibly, even though the file size becomes larger. In this regard, this technique can be applied to protect the copyright of digital products, such as software or multimedia, through digital watermarking techniques that use the EOF method to insert information or messages as permanent identification in digital files. In addition, in an effort to improve security, a technique for combining Blowfish cryptography with Hexa steganography is also proposed. This technique has advantages over DCS steganography, namely fewer pixel color changes, so that the inserted data is more difficult to detect and easier to maintain even if the stego image is processed or edited. The results of the study show that the combination of Blowfish cryptography with Hexa steganography is more effective than DCS steganography in protecting the inserted data. The test was carried out by analyzing the robustness of Hexa steganography using the PNSR test to determine the level of change in the original image and the inserted image.

Application of Diffie-Hellman Algorithm Method (Key-Exchange) in Cryptography

Sarah Sagala — 2024-12-28

In cryptography, key exchange security is essential. Because the message code can only be a message that is analyzed with a key offer that matches this message. Secret messages can be delivered through symmetric cryptographic algorithms with coded keys or with key exchange algorithms. One of the key exchange methods that has been developed is Diffie-Hellman Key-Exchange (DHKE). Diffie-Hellman is a simple method used to generate a key between two parties in order to communicate securely. The two parties running this algorithm have their own secret variables, by exchanging two public variable values and performing calculations using the received variables and secret variables obtained randomly shared secret. The security strength in this algorithm can be improved by combining an asymmetric key algorithm, namely RSA. This algorithm is not only in generating RSA keys, but also in calculating discrete logarithms in RSA and Diffie-Hellman. The results of this algorithm are key strength and confidentiality that can be used in symmetric cryptographic algorithms.

Implementation of DCT Based Steganography Algorithm to Hide Information in Images

Septrian Napitupulu — 2024-12-25

Steganography is the art and science of hiding secret messages in digital media, ensuring that only the sender and intended recipient are aware of its existence. One of the widely used techniques in digital image steganography is the Discrete Cosine Transform (DCT) based method, which embeds secret data into the frequency domain of an image. This study explores the application of DCT-based steganography to hide information in an image while maintaining its visual integrity. The research methodology involves transforming the image into DCT coefficients, embedding the secret message into selected high-frequency coefficients, and then applying the Inverse Discrete Cosine Transform (IDCT) to reconstruct the stego image. The quality of the modified image is evaluated using the Peak Signal-to-Noise Ratio (PSNR) and Mean Square Error (MSE) metrics. The results show that the proposed method effectively hides information while maintaining image quality, as indicated by the high PSNR value and minimal MSE. This study contributes to the field of secure data communication by presenting a reliable and undetectable approach to information hiding.

Analysis of Cryptographic Utilization with Merkle-Damgård Algorithm

Peronika Ulianti Nainggolan — 2022-09-25

Cryptography plays an important role in data security, especially in authentication and digital signatures. One method that is widely used in cryptographic hash functions is the Merkle-Damgård algorithm. This algorithm allows the transformation of variable-sized data into a fixed hash value through an iterative process with a compression function. This study aims to analyze and understand the working mechanism of the Merkle-Damgård algorithm and its implementation in a data security system. The methods used in this study include the hashing process by dividing messages into fixed blocks, adding padding, initializing the initial value, and iterating the compression function. Testing was carried out with the example of the plaintext "ABC" using a simple XOR operation. The results of the analysis show that the Merkle-Damgård algorithm can produce unique and deterministic hash values, making it effective in detecting data changes. However, this algorithm also has weaknesses against collision attacks, which is a challenge in its development. Therefore, a deep understanding of this algorithm is essential in improving the security of modern hash functions.