## 5 Steganalysis of the Proposed Method
In a Hermitian positive definite matrix, you would typically select specific elements to embed the data. Each selected matrix element is modified to encode one or more bits of the hidden information. The exact method for encoding these bits will depend on the specific algorithm or approach being used. Common techniques include LSB (Least Significant Bit) replacement, quantization, or other mathematical transformations. The bit distribution pattern and order within the matrix are essential (see Figure 16). Depending on the algorithm, you might embed the bits in a specific order, such as row-wise, column-wise, or diagonally, or following a more complex pattern to enhance security. The number of bits that can be hidden within a Hermitian positive definite matrix depends on its size and properties. Larger matrices typically have a higher capacity. The specific capacity should be known and considered to ensure the data fit within the matrix without distortion. In the case of applying the proposed model, the distribution of bits in R, G, and B channels can be seen to be fairly even, which means that all channels are equally burdened (see Figure 17). Now, we will test the proposed data-hiding technique using the Hermitian positive definite matrix through five created attacks:  
* X1: Cipher Text Attack--analyzes a chosen ciphertext corresponding to its plaintext. The attacker tries to obtain a secret key or the details about the system. By analyzing the chosen ciphertext and relating it to the plaintext, the attacker attempts to guess the key. Figure 16: Distribution of bits in the stego-image. Figure 17: Uniform distribution on R, G, and B channels in the stego-image. X2: Plain Text Attack--access to both the plaintext and the corresponding ciphertext. The attacker tries to deduce the secret key or the encryption algorithm by analyzing the relationship between the plaintext and the ciphertext. * X3: Brute Force Attack--try every possible key on a piece of ciphertext until they obtain an intelligible translation of ciphertext into plaintext. * X4: Noise Attack--introduces random noise into the steganographic system to disrupt the hidden message. The goal is to make the hidden message undetectable or unreadable. * X5: Corruption Attack--intentionally corrupts the steganographic system or the hidden message to render it useless or unreadable. We tested 12 examples. Each of these test examples passed through a check and a certain type of attack. Table 2 shows the number of found messages from a total of 250 samples (A) and the detection percentage (B). When it comes to attacks X1, X2, X4, and X5, it can be seen that the percentage of those detected does not exceed 1.6%. When it comes to the X3 attack, the percentage of detected cases is up to 2.8% (see Scheme 1). \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline  & \multicolumn{2}{c}{**X1: Cipher Text**} & \multicolumn{2}{c}{**X3: Brute Force**} & \multicolumn{2}{c}{**X5: Corruption**} \\  & \multicolumn{2}{c}{**Attack**} & \multicolumn{2}{c}{**X2: Plain Text Attack**} & \multicolumn{2}{c}{**Attack**} & \multicolumn{2}{c}{**X4: Noise Attack**} & \multicolumn{2}{c}{**Attack**} \\ \hline \begin{tabular}{c} **Key** \\ **(HPDM)** \\ \end{tabular}  & **A** & **B** & **A** & **B** & **A** & **B** & **A** & **B** & **A** & **B** \\ \hline T1 & 3 & 0.012 & 4 & 0  
In addition, we also checked how the length of the hidden secret message affects it (see Table 3). In this case, it can be observed that with the increase in the number of characters of the secret message, the percentage of revealed data decreases significantly. This method becomes more secure and resistant to all five types of attacks when the number of characters is above **850**. The next analysis was performed in Table 4. This testing is based on the following criteria: Image Type, Image Resolution, and Message Length. Based on that, the following results were analyzed: embedding capacity (bytes), SSIM (Structural Similarity Index), Execution Time (ET), and Detection Rate (ER).