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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Application of Statistical and Neural Network Algorithms in Steganographic Synthesis and Analysis of Hidden Information in Audio and Graphic Files⋆</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Yuliia Kostiuk</string-name>
          <email>y.kostiuk@kubg.edu.ua</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Pavlo Skladannyi</string-name>
          <email>p.skladannyi@kubg.edu.ua</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Karyna Khorolska</string-name>
          <email>k.khorolska@kubg.edu.ua</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Volodymyr Sokolov</string-name>
          <email>v.sokolov@kubg.edu.ua</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Hennadii Hulak</string-name>
          <email>h.hulak@kubg.edu.ua</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Borys Grinchenko Kyiv Metropolitan University</institution>
          ,
          <addr-line>18/2 Bulvarno-Kudryavska str., 04053 Kyiv</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Institute of Mathematical Machines and Systems Problems of the National Academy of Sciences of Ukraine</institution>
          ,
          <addr-line>42 Ac. Glushkov ave., 03680 Kyiv</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
      </contrib-group>
      <fpage>45</fpage>
      <lpage>65</lpage>
      <abstract>
        <p>This paper presents a hybrid approach for steganographic embedding and detecting information within audio and graphical containers, utilizing statistical analysis and neural networks. This study establishes the feasibility of employing auto-associative networks for steganographic synthesis and the Cumulative Sum (CUSUM) algorithm for identifying structural changes introduced by hidden content. A comparative analysis evaluates its effectiveness against other methods, including the Least Significant Bit (LSB) technique and the short-time Fourier Transform Combined with a Deep Neural Network (STFT-DNN). The findings demonstrate the superiority of the proposed hybrid architecture in terms of detection accuracy, Bit Error Rate (BER), and peak Signal-to-Noise Ratio (PSNR). Furthermore, the research investigates the efficacy of combined steganography analysis algorithms designed to operate under limited a priori information conditions and high container variability. The results underscore the significant potential of integrating machine learning and statistical modeling to develop intelligent digital security systems to counter hidden threats, protect copyright, and detect manipulative content in the contemporary information environment.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;steganography</kwd>
        <kwd>steganalysis</kwd>
        <kwd>hidden information</kwd>
        <kwd>audio container</kwd>
        <kwd>graphic container</kwd>
        <kwd>statistical modeling</kwd>
        <kwd>neural networks</kwd>
        <kwd>autoencoder</kwd>
        <kwd>digital security</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>The rapid proliferation of digital technologies and the corresponding growth of multimedia
content, particularly graphic and audio files, have escalated threats related to confidential
information leakage, covert data exchange, and copyright infringement. In this context,
steganographic methods, which involve embedding messages within digital media, are becoming
critically important as tools for ensuring information security. Audio and graphic files serve as
effective containers for hidden information due to their large capacity, inherent signal redundancy,
and the insensitivity of human perception to minor distortions, facilitating the effective masking of
embedded data.</p>
      <p>However, traditional steganographic methods, such as least significant bit (LSB) substitution,
discrete cosine transform (DCT), and discrete wavelet transform (DWT), exhibit limited resilience
against modern steganalysis techniques. Moreover, classical statistical approaches are often
insufficient for detecting complex or adaptive forms of hidden data, especially under conditions of
active digital monitoring. In response to these limitations, current research is focused on
developing hybrid methods that integrate statistical analysis with deep learning algorithms, such as
autoencoders, convolutional neural networks (CNNs), recurrent neural networks (RNNs), and
generative adversarial networks (GANs).</p>
      <p>These intelligent models facilitate the creation of embedded structures that replicate the natural
statistics of the host container, thus minimizing artifacts detectable by conventional steganalysis.
Autoencoders, for instance, generate a latent representation of the message, allowing data to be
embedded without significantly altering the signal. Similarly, Generative Adversarial Network
(GAN) models can produce containers that carry hidden information and maintain a statistical
distribution consistent with the original media. Conversely, modern steganalysis employs classifier
ensembles, change-detection algorithms (e.g., PCA or SVM), and deep neural detectors. These
detectors are trained on contrasting examples of authentic and steganographic files, enabling them
to identify modified containers even when the embedded signal is faint.</p>
      <p>In the context of digital censorship and evolving cyber threats, the primary requirements for
effective steganographic systems include the undetectability of transmission, accuracy of message
reconstruction, resilience to attacks and distortions (such as JPEG compression or noise), and
adaptability to various media types. Integrating statistical estimation and neural network
processing is pivotal for achieving a higher steganography analysis and synthesis standard. For
instance, statistical indicators such as mean, variance, and correlation coefficients can be employed
to assess the vulnerability of specific regions within an image or audio file to steganographic
embedding [1, 2]. Concurrently, neural network components are utilized for the actual data
insertion or detection, ensuring an optimal balance between embedding efficiency and
imperceptibility [3, 4].</p>
      <p>This study uses statistical and neural network algorithms to analyze modern hybrid methods for
embedding and detecting hidden information within graphic and audio files. The primary focus is
on intelligent models capable of robustly encoding hidden data, even when subjected to digital
attacks or censorship filters. The paper proposes a steganographic system architecture comprising
modules for statistical evaluation, neural network-based container generation, deviation analysis,
and Explainable AI (XAI) for interpreting and identifying hidden features. The system was
evaluated on open audio and graphic datasets, using PSNR, SSIM, BER, and AUC/ROC as
performance metrics for steganalysis. The results demonstrate that these hybrid methods
outperform traditional models in accuracy and detection resistance.</p>
      <p>Consequently, integrating statistical and neural network algorithms for steganographic
synthesis and analysis presents significant potential for developing flexible, adaptive, and reliable
information protection systems in the rapidly evolving digital landscape. The applications for such
systems extend beyond privacy protection to include digital watermarking, cybersecurity,
anticensorship measures, and secure data storage.</p>
      <sec id="sec-1-1">
        <title>Literature analysis review</title>
        <p>
          In modern steganography research, deep learning methods are being actively implemented to
enhance information concealment and detection efficiency. Specifically, Pham Huu Quang et al. [
          <xref ref-type="bibr" rid="ref1">5</xref>
          ]
proposed a steganography method that utilizes deep neural networks to embed audio signals into
images. Their approach effectively preserves the integrity of the host image and the audio data,
demonstrating superior performance over traditional methods. In the field of steganalysis,
Ghasemzadeh and Kayvanrad [
          <xref ref-type="bibr" rid="ref2">6</xref>
          ] conducted a comprehensive review of audio steganography
detection methods, emphasizing that the combination of feature calibration and higher-order
statistical moments can significantly improve the accuracy of identifying hidden messages.
        </p>
        <p>
          In 2019, Felix Kreuk et al. [
          <xref ref-type="bibr" rid="ref3">7</xref>
          ] introduced a speech steganography approach that integrates the
short-time Fourier transform (STFT) and its inverse as differentiable layers within a deep neural
network. This architecture allows for effectively embedding messages into audio signals while
preserving speech quality and ensuring robustness against distortions. In 2023, Mohamed C.
Ghanem et al. [
          <xref ref-type="bibr" rid="ref4">8</xref>
          ] developed the StegoHound method, which integrates multiple approaches for
effectively detecting and extracting digital evidence concealed within WAV and MP3 files using
steganographic techniques. This method demonstrates superior accuracy and broader detection
capabilities compared to conventional systems, particularly in analyzing large audio files. Recent
research indicates a clear trend toward integrating statistical methods with neural network
architectures to develop more robust and effective steganographic systems.
3.
        </p>
      </sec>
      <sec id="sec-1-2">
        <title>Models and methods</title>
        <p>This study employed a comprehensive approach to the steganographic synthesis and analysis of
hidden information within audio and graphic files, leveraging methods from mathematical
statistics, probabilistic modeling, and decision theory. This framework facilitated the development
of generalized mathematical models for embedding and detecting hidden messages. These models
account for both the structural characteristics of the host container and the parameters of external
influences, such as digital noise, distortions, and compression.</p>
        <p>Artificial neural networks constitute the core of the software implementation, enabling
automatic feature extraction and the adaptive processing of complex media signals. Specific
network architectures were selected based on the media type: autoencoders were employed for
steganographic data compression and recovery tasks; convolutional neural networks (CNNs) were
utilized for graphic files, where preserving the spatial correlation of pixels is crucial; and recurrent
neural networks (RNNs), particularly Long Short-Term Memory (LSTM) variants, were applied to
audio signals, which are characterized by a sequential temporal structure.</p>
        <p>All algorithms were implemented using object-oriented programming principles, ensuring a
flexible and modular system design that facilitates code reusability and scalability. Comprehensive
testing was conducted to validate the performance of the developed models. This evaluation
included statistical assessment methods, such as error analysis and detection probability
calculations, and simulation modeling within a variable digital environment. The simulations
incorporated various real-world conditions, including the addition of noise, re-encoding, and
truncation of media file fragments.</p>
        <p>The experimental results confirmed that integrating statistical methods and neural network
algorithms enables high-accuracy detection of hidden information, even in significant noise or
aggressive digital interference with the host containers. Furthermore, this combined approach
provides adaptability to various media data formats and types, a feature of critical importance in
real-world applications such as digital watermarking, secure message storage, and covert data
transmission under censorship or information blockade.
4.</p>
      </sec>
      <sec id="sec-1-3">
        <title>Main material</title>
        <p>
          As cyber threats escalate and digital communications face increasing scrutiny, steganography is
becoming an essential tool for covert data transmission. In contrast to cryptography, which
obscures the content of a message, steganography conceals the existence of the communication
itself, a critical feature for circumventing surveillance and censorship. Consequently, integrating
neural networks and statistical methods into steganographic systems is a rapidly advancing area of
research, significantly enhancing the efficiency of embedding and detecting information within
audio and graphical containers [
          <xref ref-type="bibr" rid="ref3 ref5">7, 9</xref>
          ].
        </p>
        <p>
          The paper presents a mathematical model of a stego system and discusses approaches to stego
synthesis and stego analysis, particularly using autoassociative, convolutional, and feed-forward
neural networks [
          <xref ref-type="bibr" rid="ref1 ref2 ref3 ref4 ref5">5–9</xref>
          ]. The basis of functioning is formalized through a pair of functions. F 1 and
F 2, F 1 ( z , d ) is responsible for embedding a message d in a container z , а F 2 ( z~ ) is responsible for
its recovery while minimizing distortion:
z = F 1 ( z , d ) , |z −z~|→ min ,
(1)
where F 1 is the embedding function, F 2 is the extraction function. Eq. (1) describes a generalized
steganographic model in which a function modifies a container z , F 1 with an embedded message d ,
and the inverse function F 2 allows recovery of this message [
          <xref ref-type="bibr" rid="ref1 ref2 ref3">5–7</xref>
          ]. Within the framework of
~
steganography, the main condition is to minimize the distortion of the container |z −z |, which
~
ensures the invisibility of the embedded data, as well as the accuracy of extraction d ≈ d , which
ensures the reliability of transmissions.
        </p>
        <p>
          Fig. 1 shows the architecture of a two-component neural system for steganography: model (a)
implements the embedding of messages in a container vector with minimal distortion using a
twolayer auto-associative network [
          <xref ref-type="bibr" rid="ref5">9</xref>
          ], and model (b) is a feed-forward neural network that classifies
hidden content based on statistical and structural deviations, learning from “clean” and modified
containers [
          <xref ref-type="bibr" rid="ref2 ref6">6, 10</xref>
          ]. For efficient information embedding, it is advisable to use a two-layer
autoassociative neural network with the number of neurons in the hidden layer equal to the container
dimension g =n (Fig. 1a). This architecture ensures compression, adaptation to the digital
environment (audio or graphics), and resistance to attacks. For information extraction,
feedforward neural networks are used (Fig. 1b), which implement a binary decision rule necessary for
message reconstruction [
          <xref ref-type="bibr" rid="ref3">7</xref>
          ].
        </p>
        <p>
          In digital steganography, there is a growing interest in intelligent models that facilitate both
adequate concealment and accurate detection of information embedded within digital containers.
This encompasses steganographic synthesis (the embedding of hidden data) and steganalysis (the
detection of hidden content), which are increasingly implemented using artificial neural networks
of various architectures [
          <xref ref-type="bibr" rid="ref5 ref7">9, 11</xref>
          ]. Convolutional Neural Networks (CNNs) excel at identifying local
anomalies in images and audio spectrograms that arise from covert embedding processes [
          <xref ref-type="bibr" rid="ref7 ref8 ref9">11–13</xref>
          ].
Autoencoders enable message concealment within their latent representations with minimal
container distortion, proving effective in both graphic and audio domains [
          <xref ref-type="bibr" rid="ref1 ref10">5, 14</xref>
          ]. Recurrent Neural
Networks (RNNs) are adept at processing sequential data, such as audio and video, by accounting
for temporal dependencies, which are particularly important for dynamic signals. Deep Neural
Networks (DNNs) perform multilevel signal transformations, detect latent patterns, and integrate
diverse features (statistical, spatial, spectral) to classify and identify hidden content [
          <xref ref-type="bibr" rid="ref11 ref12 ref13 ref2">6, 15–17</xref>
          ].
These advanced architectures allow for the development of adaptive steganographic systems that
can operate effectively in complex environments with limited a priori information, providing high
accuracy and robust resistance to steganalysis.
        </p>
        <p>
          The effectiveness of embedding and recovering hidden data is quantified using several digital
signal quality metrics. The Peak Signal-to-Noise Ratio (PSNR) measures the degree of container
distortion after message embedding [
          <xref ref-type="bibr" rid="ref5">9</xref>
          ], while the Structural Similarity Index Measure (SSIM)
assesses the perceptual similarity between the original and the modified object [
          <xref ref-type="bibr" rid="ref14">18</xref>
          ]. Additionally,
the Bit Error Rate (BER) determines the proportion of errors that occur during the reconstruction
of the hidden message [
          <xref ref-type="bibr" rid="ref15">19</xref>
          ]. These metrics facilitate an objective assessment of a steganographic
system’s quality, particularly its ability to preserve the visual or auditory integrity of the container
while ensuring the accurate extraction of hidden information.
        </p>
        <p>
          Fig. 2 illustrates the architecture of a neural network designed for the steganographic
embedding and subsequent analysis of audio and image files. The model comprises an input layer, a
hidden layer with g neurons, and an output layer that yields the modified container and the
recovered message. This core structure is augmented by several specialized modules: a steganalysis
module for performance evaluation using PSNR, SSIM, and BER metrics; a cryptographic module
responsible for encryption, key management, and integrity verification; and an Explainable AI
(XAI) module that utilizes methods such as SHAP and LIME for decision interpretation [
          <xref ref-type="bibr" rid="ref7 ref8">11, 12</xref>
          ].
This integrated design results in a flexible, adaptive, and resilient system with high accuracy and
operational transparency.
        </p>
        <p>
          The signal supplied to the input of a neural network that implements steganographic
information synthesis (SIS) can be represented as a combined vector [
          <xref ref-type="bibr" rid="ref10 ref16 ref3 ref4 ref5">7–9, 14, 20</xref>
          ]:
y =( dz T )=y 1+y 2 ,
        </p>
        <p>T
y 1=( z 1 , z 2 , … , z n ,0 , … ,0 )T ,
y 2=( 0 , … ,0 , d 1 , … , d m )T ,
(2)
(3)
where d = { d 1 , … , d m } is a vector containing the elements of the message to be hidden.</p>
        <p>
          In the case of hiding a complete message, which forms a data sequence d ( p ), p =1 , … , P , each of
its elements corresponds to a separate fragment of the container described by the vector z ( p ),
where p =1 , … , P [
          <xref ref-type="bibr" rid="ref6 ref8">10, 12</xref>
          ]. At the output of the pre-trained neural network, a sequence of modified
fragments of the container z´ ( p ), is formed, which already contains hidden information.
        </p>
        <p>
          The neural network is trained using a back-propagation algorithm to minimize the Mean
Squared Error (MSE) between the original message and the reconstructed data extracted from the
modified container. This approach provides practical steganographic synthesis, especially in
processing audio signals and graphic files with high dimensionality and complex structure [
          <xref ref-type="bibr" rid="ref6 ref9">10, 13</xref>
          ].
In addition, considering the container’s local properties, element-by-element embedding increases
the resistance to detection, including steganalysis attacks based on statistical and neural network
methods.
        </p>
        <p>However, modern steganalysis can detect even minor deviations in the statistical characteristics
of the signal resulting from modifications during embedding. In particular, analyzing residual
noise, spectral density, and local entropy allows you to form features sensitive to hidden content.
Neural network steganalysers trained on a large number of examples of both clean and modified
containers demonstrate a high ability to classify such embeddings. In this regard, testing for
resistance to such attacks is necessary to evaluate the effectiveness of any steganography method.</p>
        <p>
          To analyze the regularities of the steganographic information synthesis (SIS) process, within the
framework of the proposed approach, a statistical model of the container is considered, according
to which each fragment of the container is considered as a realization of a random vector z , with
zero mathematical expectation and a known correlation operator [
          <xref ref-type="bibr" rid="ref17">21</xref>
          ]:
        </p>
        <p>E [z ]=0 , E [z z T ]= Rz .</p>
        <p>The elements of the sequence of the embedded message d are modeled as independent
realizations of a binary random variable d i, which does not depend on the container z and has an
equal probability distribution:</p>
        <p>P ( d i =1 )=0.5 , P ( d i =−1 )=0.5 , E [d i ]=0 , E [d i2]=σ 2d =1.
(5)</p>
        <p>
          The statistical representation of the container z and the message d allows us to estimate the
effect of the embedded information on the signal distribution, which is critical for imperceptible
embedding without significantly changing the correlation characteristics [
          <xref ref-type="bibr" rid="ref11 ref7">11, 15</xref>
          ]. To do this, it is
advisable to use a neural network with the number of neurons in the hidden layer one unit less
than the input/output dimension (Fig. 1a), which provides compression and adaptation to data
statistics [
          <xref ref-type="bibr" rid="ref3 ref8">7, 12</xref>
          ]. The model of the container as a zero random vector with a known correlation
operator allows us to identify how hidden data changes its distribution, which is the basis of
effective steganalysis.
        </p>
        <p>The neural network is trained on a set of realizations of the input vector:
y ( p )=( z ( p )</p>
        <p>d ( p ) ) , p =1 , … , P ,
by minimizing the mean square functional of the recovery error:</p>
        <p>E =
1 P</p>
        <p>
          ∑ ( y ( p )−W 2 W 1 y ( p ) )T ( y ( p )−W 2 W 1 y ( p ) ) ,
P p=1
(4)
(6)
(7)
where W 1 and W 2 weight matrices of the neural network [
          <xref ref-type="bibr" rid="ref18">22</xref>
          ]. This approach minimizes container
distortion and prevents detection of hidden information by using modern steganalysis tools,
particularly those based on artificial intelligence and deep learning.
        </p>
        <p>
          The neural network for SIS functions as an intelligent encoder that learns to embed the message
d ( p ) into the structure of the container z ( p ) with minimal distortion and ensuring reliable
extraction [
          <xref ref-type="bibr" rid="ref13 ref9">13, 17</xref>
          ]. To detect data, a second network is used that performs classification by
detecting changes in the statistical characteristics of the signal. This combination of architectures
guarantees high secrecy, decoding accuracy, and attack resistance. Neural network methods allow
building adaptive, scalable, and invisible steganography systems suitable for information security,
digital forensics, copyright protection, and media cybersecurity.
        </p>
        <p>
          The auto-associative architecture minimizes distortion and residual traces, preserving the
features of the container and balancing between secrecy and quality [
          <xref ref-type="bibr" rid="ref18">22</xref>
          ]. Adapting to local signal
features forms a stable internal representation capable of carrying hidden information. During
training, compression is performed with minimal distortion, which allows masking data in audio
and graphic files without losing visual or acoustic quality. The system preserves the statistical and
structural integrity of the container, providing effective and subtle hiding even in complex
multimedia environments.
        </p>
        <p>However, these properties make a container (a multimedia file containing hidden information)
vulnerable to deep steganalysis, detecting hidden messages by analyzing statistical and structural
changes in data. Such analysis focuses on detecting minor changes resulting from steganographic
embedding, even if they are subtle visually or acoustically, but manifest themselves in
highdimensional feature spaces (i.e., in many statistical signal characteristics).</p>
        <p>For this purpose, spectral filtering methods are used (analysis of the frequency components of
the signal, for example, using a discrete cosine or Fourier transform), PCA (Principal Component
Analysis), which allows to detect changes in the internal structure of data by reducing their
dimensionality, and anomaly detection methods (i.e., algorithms that look for unusual or atypical
deviations from the expected behavior of data).</p>
        <p>Particular attention is paid to changes in the distributions of auto-encoder residuals, which are
the differences between the input and the reconstructed signal in an auto-encoder (a neural
network that learns to compress and reconstruct data). If these residuals show systematic
deviations, it can serve as an indicator of hidden content.</p>
        <p>Thus, even if masking (i.e., hiding information) is performed using an auto-associative
architecture (an auto-encoder that learns to reproduce itself), it still needs to be tested for
resistance to modern steganalysis algorithms—otherwise, there is a risk of detecting a hidden
message even in a complex multimedia environment.</p>
        <p>
          As a result of the theoretical analysis, the following statement has been proved: the
transformation performed by a linear two-layer auto-associative neural network (Fig. 1a) trained
according to the criterion of minimizing the mean square error is equivalent to the use of a linear
operator [
          <xref ref-type="bibr" rid="ref13 ref17">17, 21</xref>
          ]:
        </p>
        <p>W = Ryn Ry+n =W 2 W 1 ,
(8)
where Ryn is the singular (degenerate) matrix formed based on the sample covariance matrix
between the input data y ( p ), Ry+n is its pseudo-inverse matrix in the Moore-Penrose sense, q is the
number of neurons in the hidden layer, m +n −q is the number of discarded (zeroed) eigenvalues in
the diagonalization process.</p>
        <p>
          Thus, the neural network implements the optimal linear mapping with compression, preserving
the statistically significant components of the vector y , which includes the container z and the
message d [
          <xref ref-type="bibr" rid="ref1 ref10 ref18 ref5">5, 9, 14, 22</xref>
          ]. To evaluate the possibility of recovering hidden data in the process of
steganographic synthesis, the paper proposes a methodology for analyzing the statistical
characteristics of the original vector z after processing by a neural network [
          <xref ref-type="bibr" rid="ref17 ref9">13, 21</xref>
          ]. In particular,
deviations from the original distribution, changes in the covariance structure, and the possibility of
using steganalysis methods to detect hidden content are evaluated. This approach allows us to form
a formalized detection profile based on the empirical patterns inherent in modified containers. The
spectral and autocorrelation analysis will enable us to detect anomalous patterns characteristic of
the influence of steganographic embeddings. Classifiers trained on feature vectors that include
changes in entropy and local consistency are also involved in improving the detection accuracy.
Thus, steganalysis is essential in assessing the method’s resistance to unauthorized detection of
hidden information.
        </p>
        <p>
          The neural network (Fig. 1a) is fed with test signals that model hypothetical states of a hidden
message [
          <xref ref-type="bibr" rid="ref3">7</xref>
          ]:
1. y +=( 0,0 , … ,0 ,1 )T is a signal that corresponds to the hypothesis H 1 (presence of bit “+1”
in the message);
2. y –=( 0,0 , … ,0 ,−1 )T is a signal that corresponds to the hypothesis H 2 (presence of the “–1”
bit).
        </p>
        <p>The output of the neural network generates vectors y + and y –, which can be represented as:
where m± is the mathematical expectation (average values) of the useful signal that corresponds to
the hypotheses about the value of the hidden bit.</p>
        <p>Next, to assess the impact on the structure of the container, we analyze the covariance matrix of
the output signal (only the first n components corresponding to the container vector z ), when a
random vector y x =( z 1 , z 2 , … , z n ,0 )T is applied. To do this, the matrix is calculated:
~
R =W 2 W 1 Ry W 1T W 2T ,
z =α m++( 1−α ) m–+η ,
where Ry is the covariance matrix of the input signal. The block part ⋀ z, is extracted from it,
which corresponds to the submatrix for the container.</p>
        <p>
          As a result, the output signal can be represented as:
where α =1 for d =1, α =0 for d =−1, and η is a fluctuating noise that models the residual content
of the container [
          <xref ref-type="bibr" rid="ref6 ref8">10, 12</xref>
          ]. This expression shows how the structure of the container changes due to
steganographic embedding: the signal z is the sum of mathematical expectations for the
corresponding bit and the noise component [
          <xref ref-type="bibr" rid="ref11 ref2">6, 15</xref>
          ]. These changes allow us to build adequate
detectors for detecting embedded information even under distortion. For this purpose, steganalysis
uses methods for estimating residual noise η, which are key indicators of the presence of a hidden
message. In particular, analyzing the moving average, variance, and higher statistical moments
allows us to identify atypical fluctuations associated with steganographic activity. In addition,
comparing the empirical distributions of m⁺ and m⁻ will enable us to assess the symmetry of the
signal and detect shifts caused by embedding. These characteristics are widely used in machine
learning-based detectors that detect hidden information even at low signal-to-noise ratios.
        </p>
        <p>To recover the hidden bits, it is necessary to perform a binary classification: to determine which
class a vector z belongs to based on the mathematical expectations m+ and m–, in the presence of
noise with a known covariance matrix ⋀ z. The neural network identifies the message bits by
comparing the signal with the typical built-in states.</p>
        <p>
          In steganalysis, the classification task is reduced to the implementation of an ML equation
(maximum likelihood rule) that formalizes the optimal solution: to determine whether the
container contains a “+1” or “–1” bit. A neural network trained on the differences between m+ and
–
m , acts as a stego-decoder. To do this, we use a network (Fig. 1b) that implements ML
classification. With Gaussian noise, the solution is as follows:
(10)
(11)
where R is the noise covariance matrix [
          <xref ref-type="bibr" rid="ref17 ref19 ref8">12, 21, 23</xref>
          ]. This ensures the detection of hidden data even
with partial signal distortion.
        </p>
        <p>
          The expression determines the error probability when recovering the bits of a hidden message:
P err= P ( H 1 )+ P ( H 2 )=1−Φ ( α ) , α =0.5 ∙ ( m+−m– )T R−1 ( m+−m– ) ,
(13)
where Φ ( α ) is the probability function of the standard normal distribution [
          <xref ref-type="bibr" rid="ref13 ref9">13, 17</xref>
          ]. This
expression quantifies the quality of steganographic concealment: the smaller P err, the more reliably
the hidden information is recovered, even in noise or distortion. This assessment allows us to
measure the effectiveness of various steganographic methods in practice objectively.
        </p>
        <p>The probability of erroneous bit recognition, as defined by Eq. (13), serves as a key indicator of
decoding accuracy under conditions of uncertainty. Minimizing this probability indicates
highquality embedding and robust resilience to attacks, even when an adversary possesses partial
knowledge of the container or the embedding methodology. Utilizing a linear neural network
reduces the embedded message’s amplitude relative to the training phase, thereby minimizing
container distortion without sacrificing decoding accuracy—a critical factor for ensuring stealth.</p>
        <p>
          To evaluate the system’s robustness, a series of typical steganalysis attacks was modeled,
including the introduction of noise, signal clipping, spectral modifications, and compression.
Experiments simulating an active adversary with knowledge of the embedding technique
confirmed the system’s high level of imperceptibility when the decoder is configured correctly.
Attacks employing alternative network architectures proved ineffective, primarily due to the
challenges of data sampling and the extensive training time required, which significantly
complicates reverse engineering efforts [
          <xref ref-type="bibr" rid="ref6">10</xref>
          ]. The system demonstrates remarkable adaptability to
real-world distortions (e.g., compression, filtering, and signal conversion). It maintains high
recovery accuracy even with a message amplitude of 0.5 and noise levels up to 10⁻⁴, provided it has
been trained on data with comparable characteristics.
        </p>
        <p>
          For stable model training and high accuracy, preliminary signal normalization is recommended.
High-resolution and lossless formats, such as BMP, TIFF, and PNG for graphics, and WAV or FLAC
for audio, are ideally suited for this purpose. In an experiment using 24-bit PNG images, a linear
neural network achieved a bandwidth of 0.3 bits per pixel while maintaining a PSNR greater than
50 dB, a visually imperceptible distortion level [
          <xref ref-type="bibr" rid="ref15">19</xref>
          ]. It is advisable to employ deeper architectures,
such as convolutional autoencoders (CAEs) and transformers, to enhance efficiency and security
further. These models can adapt to different media types and conceal more complex messages with
minimal distortion.
        </p>
        <p>Fig. 3 illustrates the logical framework for evaluating the robustness of a neural network-based
steganography method. The process commences with selecting a host container (either an audio or
image file) into which the neural network embeds data. Subsequently, the system is subjected to
simulated steganalysis attacks, including introducing noise, cropping, and compression, as well as
modeling the actions of an active adversary. Following an attempted decoding of the embedded
data, the accuracy and throughput of the system are evaluated. Its parameters are systematically
adjusted if the attack fails to disrupt the message. The influence of the embedded signal’s amplitude
is also analyzed, and the entire procedure is iterated for various container types to ensure
comprehensive validation.</p>
        <p>Fig. 4 illustrates the architecture of a system designed for steganographic synthesis and analysis
using neural networks. It comprises distinct modules for container formation, data embedding,
attack simulation, message decoding, and performance evaluation. The neural network training
module is a key component that adapts the system to the specific media type being processed
(audio or graphics). The interaction between these modules facilitates a comprehensive testing
cycle to evaluate the system’s robustness against various steganalysis attacks.</p>
        <p>Fig. 5 illustrates the sequence of operations within the steganographic experiment, detailing the
interaction logic among the system’s modules. The process begins with the researcher defining the
experimental parameters, after which a host container (audio or graphic) is prepared and the
message is embedded. Subsequently, the container is subjected to simulated steganalysis attacks,
such as the introduction of noise, cropping, and compression. The decoding module then attempts
to extract the embedded data. Finally, key performance metrics—accuracy, PSNR, and efficiency—
are automatically recorded and compiled into a report for subsequent analysis.</p>
        <p>
          This study introduces a hybrid algorithm for detecting steganographic embeddings, which
combines the neural network-based reconstruction of a container’s inherent statistical structure
with the parametric monitoring of any resulting changes [
          <xref ref-type="bibr" rid="ref3 ref4 ref5">7–9</xref>
          ]. The methodology is founded upon
an autoregressive (AR) model of the signal or image. This model is initially established by a linear
neural network trained on a dataset of unmodified containers. The subsequent detection of hidden
data is accomplished by analyzing any deviations from the established AR model’s predictions.
        </p>
        <p>
          Theoretical studies prove the convergence of the network weights, which guarantees the
accuracy of the forecast and the formation of a profile of normal behavior [
          <xref ref-type="bibr" rid="ref14 ref17 ref18 ref9">13, 18, 21, 22</xref>
          ].
Deviations from its record concealment, even without knowledge of a specific algorithm. Thus, the
neural network acts as a predictor and an adaptive detector of hidden information. In steganalysis,
this allows for the detection of hidden embeddings by comparing the actual behavior of the signal
with the expected profile formed based on clean containers. In particular, a sharp increase in the
prediction error or a shift in the feature vector may indicate the presence of a hidden message.
Such approaches efficiently analyze high-dimensional data, where classical statistical methods
show insufficient sensitivity. Thus, neural networks play a key role in modern steganalysis
systems, accurately identifying steganographic influences.
        </p>
        <p>
          In the context of steganography, detecting the fact of embedding hidden information is
formalized to fix the moment of statistical imbalance in the analyzed digital sequence [
          <xref ref-type="bibr" rid="ref11 ref7">11, 15</xref>
          ]. We
consider a dataset { z t }, which is modeled by the conditional probability density P θ ( z t ), where
θ ∈ Rr is a vector of parameters describing the container’s normal (unchanged) state. The task is to
detect the moment t 0, when the parameter θ 0 changees to θ 1, which is a sign of covert
steganographic interference. Before t 0 the data distribution corresponds to the “clean” container
and is described by the density w ( z t | θ 0 ), after—to the modified container with the message
already embedded, which is described as w ( z t | θ 1 ), where θ 1 ≠ θ 0. Thus, embedding a hidden
message is considered a statistical shift in the parametric space of the model, and its detection is
the main task of intelligent steganalysis.
        </p>
        <p>
          Contemporary research, particularly the work of Michel Basseville and Alexander Tartakovsky
[
          <xref ref-type="bibr" rid="ref19 ref8">12, 23</xref>
          ], employs a modified cumulative sum (CUSUM) algorithm [
          <xref ref-type="bibr" rid="ref8">12</xref>
          ] to detect subtle changes
induced by steganographic embedding. This algorithm, which is based on the Le Cam asymptotic
decomposition, accurately identifies the point at which structural changes occur in the parameters
of a digital signal. Within the context of steganalysis, CUSUM is a tool for monitoring the stability
of the signal’s structure; when an embedded message alters the statistical characteristics, the
algorithm signals this anomaly. This approach enables the detection of the concealment itself and
allows for the localization of its point of insertion. This capability is critical for constructing
resilient digital security systems that do not require prior knowledge of the specific embedding
algorithm used.
        </p>
        <p>The formula for the accumulated statistics is as follows:
where [ x ]+=max ( 0 , x ), g t is the value of CUSUM at step t , h is the threshold for deciding
whether there are changes in the model, t a is the moment of fixing the imbalance, na is the number
of steps from the last reset of g t to fixation.</p>
        <p>The threshold h ( t ) is determined dynamically:
h ( t )=C + ln ln ( t )+2 ln ( ln ln ( t ) ) ,
(16)
where C is an empirically selected constant that considers the trade-off between sensitivity and
false alarms.</p>
        <p>
          In the context of steganalysis, the cumulative sum (CUSUM) algorithm is utilized to monitor the
statistical stability of a digital signal [
          <xref ref-type="bibr" rid="ref13 ref14">17, 18</xref>
          ]. Suppose a hidden message alters the parameters of
the signal’s underlying model. In that case, the CUSUM statistic registers these deviations, enabling
the embedding detection even without prior knowledge of the specific method employed. This
approach facilitates real-time, adaptive steganalysis and offers significant flexibility when
encountering unknown concealment techniques.
        </p>
        <p>
          The work of the neural network algorithm for detecting steganographic embedding includes
three main stages [
          <xref ref-type="bibr" rid="ref6">10</xref>
          ]:
1. Formation of an AR model of the container by training a neural network on “clean” data to
create a standard state benchmark.
2. Evaluation of deviations using the CUSUM algorithm, which captures structural changes
likely caused by SIE.
3. Detecting SIEs by analyzing the growth of the prediction error: if a neural network trained
on “clean” containers suddenly predicts the following elements poorly, it signals a possible
hidden embedding [
          <xref ref-type="bibr" rid="ref10 ref19 ref20">14, 23, 24</xref>
          ].
        </p>
        <p>
          In steganalysis, even a simple neural network can detect hidden embeddings effectively [
          <xref ref-type="bibr" rid="ref17">21</xref>
          ]. In
its most basic implementation, the network approximates an autoregressive (AR) signal model
through a single-layer linear structure that predicts the subsequent state of a container based on its
preceding values. The number of inputs is determined by the parameter d (the dimension of the
input vector), while the number of outputs, l, corresponds to the length of the predicted vector.
This configuration allows for capturing statistically significant deviations caused by the embedding
process, serving as a sensitive indicator of signal alterations without the need for complex
calculations or prior knowledge of the hidden data’s characteristics.
        </p>
        <p>
          The input influence matrix is defined as [
          <xref ref-type="bibr" rid="ref5">9</xref>
          ]:
        </p>
        <p>Y = { y 1 , y 2 , … , y N −S } ,
y i =( s i , s i+1 , … , s i+S −1 ) ,
(14)
(15)
(17)
where S is the length of the sliding window, si is the signal values can be either primary data
(pixels, samples) or secondary features (histograms, entropy, etc.).</p>
        <p>
          The output of the neural network is a vector of predicted values, which is described by a vector
autoregressive (VAR) equation of the following form:
where t =S , S +1 , … , N and W j are the weighting matrices of the neural network that realize the
passage of the input signal y t − j, A is the vector of bias in the neurons, ηt is the vector of prediction
error, with a mathematical expectation of zero and an unknown covariance matrix Rη. The
parameters W j and A are determined in the process of training the neural network on the
reference set. In the context of steganography, this equation allows modeling the expected
behavior of a digital container without embedded data, creating a reference predictive model [
          <xref ref-type="bibr" rid="ref13 ref9">13,
17</xref>
          ]. Any significant deviation between the actual signal and the predicted vector ^yt may indicate
interference caused by covert embedding [
          <xref ref-type="bibr" rid="ref11 ref2">6, 15</xref>
          ]. Thus, the neural network acts as a detector of
steganographic influence, recording anomalies that violate the statistical sequence of the signal.
        </p>
        <p>
          To detect steganographic embedding, we analyze the root mean square error of predicting the
vector y t based on a neural network trained on “clean” containers. A sudden increase in this error
signals the possible insertion of hidden information, which is recorded using the cumulative sum
statistic [
          <xref ref-type="bibr" rid="ref6">10</xref>
          ]. This approach allows for detecting steganographic influence without knowledge of
the embedding algorithm. The accumulation of errors over time ensures high sensitivity to even
minor changes in the signal structure characteristic of data masking, which allows timely and
accurate detection of hidden information in audio and graphic containers.
        </p>
        <p>Fig. 6 outlines the process for detecting steganographic embeddings within audio or image files
using a neural network. Initially, the network is trained on a dataset of unmodified (“clean”)
containers to establish a baseline model of their natural statistical properties. Subsequently, a new
container is analyzed using a sliding window methodology. An input vector is formed within each
window, the network predicts the subsequent signal element, and the root mean square error
between the expected and actual values is computed. The cumulative sum (CUSUM) algorithm is
activated if this prediction error exceeds a predetermined threshold. The CUSUM algorithm then
accumulates these errors to identify statistically significant deviations, thereby signaling a potential
hidden embedding.</p>
        <p>Fig. 7 illustrates the mean square error (MSE) dynamics generated by the neural network’s
signal prediction. For the initial 50 samples, corresponding to the unmodified portion of the
container, the MSE remains consistently low. However, immediately after the point of
steganographic embedding, a sharp increase in the MSE is observed. This spike signifies a change
in the signal’s statistical properties and is registered as an indicator of steganographic modification.</p>
        <p>The comparative evaluation is conducted under the key assumption that none of the methods
possesses a priori information regarding the concealment technique. This condition ensures an
objective assessment of the versatility and effectiveness of the hybrid NN+CUSUM approach in
detecting the presence of steganography, regardless of its specific implementation. Within this
framework, steganalysis is predicated on analyzing statistical deviations from the original signal’s
properties, which are recorded using the cumulative sum algorithm—a sensitive tool for change
detection. When combined with a neural network that establishes an adaptive baseline profile of
normal signal behavior, this methodology facilitates the detection of even subtle embeddings. This
hybrid approach minimizes false positive and false negative rates when identifying hidden content.
Notably, testing on independent datasets has demonstrated superior performance in scenarios
where the type of steganographic method or its parameters is available.</p>
        <p>The proposed method achieves superior performance, demonstrating the highest accuracy
(93.8%), the lowest bit error rate (1.5%), and the highest peak signal-to-noise ratio (PSNR) of 50.2
dB. These results confirm the hybrid system’s superiority over traditional and contemporary
methods.</p>
        <p>Figure 8 presents a comparative analysis of five steganalysis methods across three key
performance metrics: detection accuracy (%), bit error rate (BER, %), and peak signal-to-noise ratio
(PSNR, dB). The proposed hybrid method, which integrates a neural network with the CUSUM
algorithm, exhibits the highest detection accuracy (93.8%), the lowest BER (1.5%), and a superior
PSNR of 50.2 dB. In contrast, the classical Least Significant Bit (LSB) method yields markedly
inferior results, while other modern approaches, including StegoHound and the STFT-based DNN,
demonstrate comparatively lower efficacy. These findings underscore the advantages of integrating
statistical analysis with neural networks for developing robust and covert steganographic systems.</p>
        <p>1 ∑i ε 2t , j .</p>
        <p>MSE t = l j =1
g t =( 0 , g t −1+ MSE t − μ 0−δ ) ,
where y t −i is the input vector, W i is the neural network weight matrices, A is the shift vector, S is
the sliding window length.</p>
        <p>After the model is formed, the current value is predicted and the error is calculated:</p>
        <sec id="sec-1-3-1">
          <title>The root mean square error is used to evaluate the degree of deviation:</title>
          <p>
            These values are fed into the CUSUM algorithm, which accumulates deviation statistics using
the formula [
            <xref ref-type="bibr" rid="ref13 ref19">17, 23</xref>
            ]:
where μ 0 is the average error when working with “clean” containers, δ is the sensitivity threshold.
The values of the mean square error MSE t and the cumulative sum g t allow us to detect
steganographic embedding when a model trained on “clean” containers unexpectedly loses its
ability to predict subsequent values accurately. This indicates that the signal structure has been
altered by a hidden message.
          </p>
          <p>A violation is recorded if the accumulated statistics exceed the threshold g t ≥ h.
(21)
(22)
The start and end of exposure are recorded under the following conditions:
t start=arg g t &gt;0 , t end =arg g t =0.
(23)</p>
          <p>To enhance the effectiveness of the analysis, secondary characteristics can be used, in
particular, the, χ 2 is test for analyzing lower bits:
where O i is the number of observations, E i are expected values.</p>
          <p>False alarm probability assessment:</p>
        </sec>
        <sec id="sec-1-3-2">
          <title>Average detection delay time:</title>
          <p>,
P FA ( h )= P ( g t ≥ h ∨ H 0 ) .</p>
          <p>E [τ −t 0 ∨ τ &gt;t 0 ]→ min ,
(24)
(25)
(26)
where τ is the moment of fixation, t 0 is the actual start time of the steganographic impact.</p>
          <p>The proposed model demonstrates high accuracy in detecting and localizing hidden
information, effectively adapting to conditions of a priori uncertainty. The model facilitates the
precise identification of embedding boundaries by integrating neural network processing with
classical statistical control. Formalized quality metrics, including delay time and false alarm
probability, validate its suitability for implementation in real-world steganographic systems.</p>
          <p>This paper details the architecture and implementation of a software framework for embedding
and detecting hidden information within graphic and audio containers. The core of the system,
implemented in C++, integrates classical steganographic methods with proprietary algorithms to
form a multi-layered system for steganography, steganalysis, and neural network modeling.
Particular attention is given to the steganalysis module, which employs a hybrid feature set
comprising spectral coefficients, residual noise patterns, and neural network activations. This
approach enables the system to detect hidden information even when sophisticated concealment
techniques are used to preserve high visual or acoustic fidelity. Furthermore, integrating a trained
neural network facilitates the dynamic adaptation of detection thresholds according to the
container type and level of distortion. This methodology demonstrates high efficacy in test
scenarios and is suitable for the automated verification of multimedia content integrity.</p>
          <p>The analytical component of this framework is based on the combined application of statistical
and structural steganalysis methods. It integrates several techniques, including detecting
autoregressive model imbalances, comparing file service block signatures, and using the χ²
(chisquared) criterion for analyzing the least significant bits of graphic and audio signals. Support for
various formats, including BMP, PNG, GIF, JPEG, MP3, WAV, HTML, and TXT, ensures its
versatility. A key feature of this approach is integrating these classical methods with a multilayer
perceptron (MLP), which performs signal prediction and anomaly detection.</p>
          <p>To support model training independently of external machine learning frameworks, a
proprietary library was developed that enables the creation and training of MLPs, featuring flexible
parameterization and an adaptive gradient descent algorithm.</p>
          <p>To validate its effectiveness, modules were developed to simulate standard concealment
techniques, including least significant bit (LSB) modification, pseudo-random data dispersion,
context-aware embedding, and variable embedding densities. In experiments conducted on BMP
files with embedding densities up to 25%, a detection accuracy exceeding 90% was achieved, with a
Type II error rate below 1%. Integrating statistical and neural network approaches enabled the
detection of even randomly distributed embedded data. Furthermore, the CUSUM algorithm
identifies the onset and duration of statistical violations, thereby accurately localizing the
embedded segments. This research culminates in an autonomous system capable of detecting
hidden messages in digital media without prior knowledge of the embedding algorithm. Its efficacy
has been confirmed across various graphic and audio file formats, and the system’s architecture is
extensible for future applications in reverse analysis and digital forensics.</p>
          <p>The graph in Fig. 9 presents the results of an experimental study on the dependence of
steganographic detection effectiveness on the threshold value, h, in the CUSUM algorithm. The
data illustrate that as h increases, the False Negative Rate decreases significantly; however, beyond
a certain point, this is accompanied by a gradual increase in the False Positive Rate. The highest
detection accuracy is achieved when an optimal balance is struck between these two error rates,
which guides the selection of the ideal threshold, h, for the steganalysis system.</p>
          <p>Fig. 10 presents a data flow diagram (DFD) illustrating a steganographic system that integrates a
neural network with the cumulative sum (CUSUM) algorithm for detecting hidden information
within digital containers. The process is initiated when a user uploads a container to the “Analyze
Container” module, which passes the data to the “Predict Signal” block. The neural network then
computes the prediction error between the expected and actual signal values. These errors are
subsequently analyzed by the “Compute CUSUM Statistics” module to identify statistically
significant deviations.</p>
          <p>Subsequently, the Decision Module determines the presence of hidden data; the outcome is
recorded in the Result Log and conveyed to the user. Additionally, the system utilizes a reference
database of unmodified containers (the Clean Container Database) and an “Embed Hidden Data”
module to simulate various embedding scenarios. This architecture supports a comprehensive
operational cycle, from generating steganographic containers to detecting hidden content, and is
adaptable to audio and graphic data.</p>
          <p>During steganalysis, the system compares the characteristics of the container under
investigation with baseline statistics from the Clean Container Database, a process that enables the
detection of even minimal deviations. A multifactorial analysis is conducted to enhance accuracy,
incorporating prediction residuals, spectral features, and neural network responses obtained during
the modeling phase.</p>
          <p>The final determination by the Decision Module is based on an integrated metric that
aggregates the outputs from multiple detection algorithms. Consequently, the system provides
highly accurate detection of hidden information, independent of the specific steganography
algorithm.</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>Discussion</title>
      <p>The results of this study confirm the high efficacy of a hybrid approach for steganographic
embedding and detection. This approach integrates neural network modeling with a statistical
change-detection algorithm, specifically the Cumulative Sum (CUSUM) method. This synergy
allows the system to account for the deep structural features of the media container, as modeled by
the artificial neural network, while simultaneously identifying anomalous deviations through the
statistical accumulation of probabilistic features. Compared to traditional methods such as Least
Significant Bit (LSB) substitution, chi-squared (χ²) analysis, or simple histogram comparison, the
proposed system demonstrates markedly superior performance. This is evident in its enhanced
accuracy of hidden message detection and improved key quality metrics, including a lower Bit
Error Rate (BER) and a higher Peak Signal-to-Noise Ratio (PSNR).</p>
      <p>The proposed hybrid scheme, which integrates auto-associative neural networks for
constructing an adaptive latent embedding space with the CUSUM algorithm for detecting
deviations in temporal or spatial signal structures, demonstrated superior performance over other
contemporary methods. These include the Short-Time Fourier Transform with Deep Neural
Network (STFT-DNN) approach and StegoHound, a prominent image steganalysis system. Key
advantages of this integrated methodology include the high-fidelity preservation of the host
container, robustness against common attacks such as JPEG compression and noise addition, and
enhanced adaptability achieved through a flexible embedding process that conforms to the
container’s intrinsic characteristics.</p>
      <p>A key innovation of this work is the integration of Explainable Artificial Intelligence (XAI)
mechanisms, specifically through the application of tools such as SHAP (SHapley Additive
exPlanations) and LIME (Local Interpretable Model-agnostic Explanations). This integration
enables the system to automatically detect hidden messages and provide visual interpretations for
its classification decisions, thereby significantly enhancing the model’s transparency. This feature
is particularly valuable in fields such as digital forensics, where evidence-based explanations for
system outputs are a critical requirement.</p>
      <p>The developed architecture is modular and scalable, allowing for adaptation to various
multimedia container formats—including PNG, JPEG, WAV, MP3, and FLAC—and resilience
against different types of interference, such as noise attacks, re-encoding, clipping, and signal
transformations. The flexibility of this implementation facilitates the independent updating of
system components, enabling changes to the embedding strategy, the integration of new detector
types, or connection with real-time stream processing tools.</p>
      <p>Nevertheless, several limitations must be considered for practical implementation. These include
the significant computational load imposed on processors and graphics accelerators, particularly
during the model training phase, and the system’s sensitivity to the quality of the input data.
Specifically, data artifacts, unstable sampling, or unrepresentative examples can adversely affect
detection accuracy. Therefore, future work will focus on expanding the system to incorporate
transfer learning, enabling the reuse of pre-trained models in novel contexts, and integrating
federated learning to enhance data confidentiality and facilitate distributed model training without
centralized data collection.</p>
      <p>The primary advantage of the proposed method is its adaptability to diverse digital
environments. This quality ensures the adequate concealment of transmitted information, high
detection accuracy, configurational flexibility for various containers, and the capacity for
selflearning and automatic adaptation. These characteristics provide a foundation for developing a
new generation of steganographic systems capable of operating within a highly dynamic digital
environment characterized by an escalating number of attacks and a growing demand for solution
transparency.</p>
      <p>This paper proposes a steganographic embedding method that integrates neural network
modeling with statistical monitoring. A multilayer perceptron architecture was selected as the
optimal framework for concealing and detecting information, based on its balance of accuracy,
adaptability, and noise immunity. A statistical embedding model was developed that considers key
container characteristics - such as type, bit depth, and signal distribution—with BMP, PNG, and
WAV formats identified as optimal for achieving the best performance. A steganalysis module was
implemented to evaluate the method’s effectiveness by comparing the characteristics of original
and modified containers. Specifically, this module analyzes spectral features, residual noise
patterns, and histogram alterations that indicate a potential embedding. The neural network model
adapts to these statistical changes by learning to differentiate between typical and anomalous
signal variations. This integrated approach ensures high accuracy in detecting hidden information,
even within complex multimedia environments.
The convergence of the neural network’s weight coefficients during the approximation of
autoregressive models is established, ensuring the creation of a baseline profile for normal signal
behavior. A hybrid detection algorithm is proposed, which integrates neural network-based
prediction with cumulative sum (CUSUM) statistics, enabling the precise identification of an
embedding’s onset and duration. This approach allows for detecting hidden information by
analyzing deviations between the predicted and actual signal values, without prior knowledge of
the specific steganography method employed. The CUSUM algorithm effectively identifies the
cumulative signal structure changes characteristic of steganographic modification. When combined
with an adaptive neural network, this technique facilitates the detection of the concealment itself
and the estimation of its temporal or spatial localization within the data.</p>
      <p>A software framework was developed using the Borland C++Builder 6.0 environment to
implement this method. This system supports the processing of graphic and audio files,
accommodates various embedding schemes (including LSB and hybrid approaches), and integrates
statistical and neural network algorithms. In experiments conducted on BMP files with an
embedding density of 25%, the system achieved a detection accuracy exceeding 90% with an error
rate of less than 1%.</p>
      <p>The proposed method demonstrates high efficacy in detecting hidden data and is well-suited for
applications in digital forensics, multimedia stream protection, and content integrity verification.
Future development will focus on integrating deep learning architectures, support for additional
formats, and incorporating Explainable AI (XAI) to interpret detected anomalies. This will facilitate
the creation of transparent steganalysis systems, wherein model decisions are justifiable through
key signal features. The integration of deep convolutional or recurrent neural networks will
enhance the capability for real-time detection of hidden content in streaming data. Furthermore,
extending support to modern formats such as HEIF, FLAC, and WebP will broaden the method’s
applicability in contemporary media environments. Consequently, this approach has the potential
to form the basis for a new generation of adaptive digital security systems characterized by a high
degree of trustworthiness and automation.</p>
    </sec>
    <sec id="sec-3">
      <title>Declaration on Generative AI</title>
      <p>While preparing this work, the authors used the AI programs Grammarly Pro to correct text
grammar and Strike Plagiarism to search for possible plagiarism. After using this tool, the authors
reviewed and edited the content as needed and took full responsibility for the publication’s content.
[1] B. Zhurakovskyi, et al., Processing and analyzing images based on a neural network, in:</p>
      <p>Cybersecurity Providing in Information and Telecommunication Systems, 3654, 2024, 125–136.
[2] V. Dudykevych, et al., Detecting deepfake modifications of biometric images using neural
networks, in: Cybersecurity Providing in Information and Telecommunication Systems
(CPITS), 3654, 2024 391–397.
[3] B. Bebeshko, et al., Application of game theory, fuzzy logic and neural networks for assessing
risks and forecasting rates of digital currency, J. Theor Appl. Inf. Technol. 100(24) (2022) 7390–
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[4] K. Khorolska, et al., Application of a convolutional neural network with a module of
elementary graphic primitive classifiers in the problems of recognition of drawing
documentation and transformation of 2D to 3D models, J. Theor. Appl. Inf. Technol. 100(24)
(2022) 7426–7437.</p>
    </sec>
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