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Kazemi et al. / IJOCTA, Vol.15, No.4, pp.578-593 (2025)
            this method, providing links to variational princi-  contain valuable diagnostic or interpretive infor-
            ples from geometry that tend to favor structural  mation. As an example, in the medical imaging
            fidelity.                                         field, the subtle anatomical features in the image
                                                              (i.e., blood vessels or tissue boundaries) need to
            5. Comparison between tension field               be preserved and no artifact should be introduced
                and α−tension field in image                  in the denoising process. Additionally, the term
                                                                           2
                processing                                    ∇I(∇ | ∇I | ) in the 2-tension field illustrates
                                                              how the higher-order gradient information can be
            In this section, we compare the tension field to
                                                              integrated. This minute change, which reacts to
            the nonlinear α-tension field with α = 2, referred
                                                              linear differences in the strength of the gradient, is
            to as the 2-tension field. This comparison is a lens
                                                              what enables the model to automatically amplify
            on the math formulations, properties, and usages
                                                              or damp specific features so that the native image
            in image processing. The behavior of each op-
                                                              structure is maintained while still considering the
            erator is illustrated in a figure to further clarify
                                                              issue of noise.
            this comparison. After this, we display the algo-
            rithm that is used to make a comparison between
            the tension field and the 2-tension field of a 2D     The strong mathematical background of the
            image.                                            2-tension field is shown from a theoretical point
                Equation (7) demonstrated that tension field  of view by the connection between the 2-tension
            of 2D image I satisfies τ(I) = ∆(I), where ∆ is   field and geometric variational principles. This
            the Laplacian operator. This field is crucial for  provided a framework, which naturally balances
            recognizing rapid intensity changes (edges, cor-  smoothness with structure accuracy (key for good
            ners). The tension field is useful to highlight such  image processing), as can be seen in Figure 2.
            running levels; however, it suffers from one major  In contrast to traditional methods, which rely on
            flaw, which is its high sensitivity toward the uni-  static or piecewise -linear weighting techniques,
            form regions, thereby making it prone to noise.   the 2-tension field reacts according to the spa-
            This problem occurs because the tension field in-  tial characteristics of the image, proving versatile
            fers isotropic smoothing across the whole image   and adaptable in differing scenarios. By dynam-
            pixel-wise, failing to differentiate between the ac-  ically adjusting based on local conditions, such
            tual substantive parts of the image and simple    as textures and other fine transitions, it can pro-
            noise. Thus, while the tension field is good at   vide high efficiency with no unwanted artifacts.
            basic edge detection, it can fail to find a balance  Moreover, the versatility of the equation allows
            between preserving important features while elim-  it to be tailored for particular applications, such
            inating unwanted artifacts when used alone.       as medical imaging, where preserving fine details
                In contrast, the 2-tension field defined in equa-  is critical.  In brief, the 2-tension field repre-
            tion (16) takes it a step further with the use    sents a significant leap in image processing, pro-
            of higher-order terms, allowing it to dynamically  viding computationally speedy solution for de-
            throttle the tension field according to the gra-  noising, edge retention, and features enhancement
            dient norm | ∇I |. The first term of (16) dy-     tasks.
            namically adjusts the diffusion coefficient based
            on the local gradient magnitude, and the second
            term incorporates higher-order gradient informa-      Figure 2 consists of eight images that illus-
            tion. This inherently adaptive process protects   trate, step by step, how the tension field and
            those regions with high-edge structures, thus re-  each term of the 2-tension field are applied to
            taining their structural integrity. This minimizes  the input image. It also compares the perfor-
            the risk of over-smoothing in areas where noisy   mance of the tension field and the 2-tension field
            images are, while also letting through areas that  on a well-known benchmark in image processing,
            are less affected (i.e., relatively smooth) in order  highlighting their respective strengths and limi-
            to help smooth out the final image. Through an    tations. Image (a 1 ) is the original image used as
            intelligent trade- off between these effects, the 2-  input for both operators. Some features of | ∇I | 2
            tension field achieves the best performance across  are demonstrated in Image (a 2 ) which influences
            both feature preservation and noise cancellation  edge detection. On the other hand, Image (b 1 )
            tasks.                                            shows the output of the tension field as it not only
                Adaptive modulation can be very significant   efficiently detects edges but also amplifies noise
            for practical applications such as medical imaging.  in smooth regions due to its isotropic smooth-
            In this use case, it is important to retain fidelity  ing properties. To explore the 2-tension field in-
            in fine-scale structures and edges, which typically  depth, we evaluate every term of τ 2 (I) and show
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