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Kazemi et al. / IJOCTA, Vol.15, No.4, pp.578-593 (2025)
            this is the first study to systematically investigate  and α-tension field are contrasted in both mathe-
            the potential of the α-tension fields on image pro-  matical formulation and properties, as well as in
            cessing tasks. The proper noise smoothing, as     practice. Finally, Section 6 summarizes the pa-
            well as, sharp feature extraction capabilities of  per, noting implications and directions for future
            the α-tension field, stems from its exploitation of  work.
            higher-order gradient information in addition to
            being derived from geometric variational bases as  2. Geometry of tension fields and
            opposed to classical linear operators, which either  α-tension fields
            overly enhance the noise in the minimization pro-  The tension field is a fundamental notion in geo-
            cess or prevent significant image details from be-  metric variational problems, which rely on the
            ing evident. As such, it presents a mathematically  principles of energy minimization to study the
            principled and generalizable framework for ad-    structure of mappings between manifolds. These
            vanced image processing applications, including   are rooted in differential geometry and yield
            denoising, edge-preserving smoothing, and fea-    strong results on how curvature, topology, and
            ture enhancement. Additionally, the authors inte-  energy functionals restrict the behavior of map-
            grate geometrical theory with the following prac-  pings. This part has been dedicated to explor-
            tical implementations: this not only encourages   ing the geometric background under tension fields
            more efficient image-analysis processes but also  and their generalizations, which we call α− ten-
            sets the stage for future inquiry into real-time and  sion fields. We emphasize their intrinsic math-
            large-scale image-processing techniques.          ematical features and discuss how these notions
                                          9
                This work differs from Ref. in terms of the-  shed light on the relationship between energy min-
            oretical contributions, methodologies, and novel  imization and the geometrical structure of map-
                                   9
            applications. The paper defines (α, f)-harmonic   pings.
            maps and checks how stable they are under differ-     Let M and N be smooth Riemannian mani-
            ent geometric conditions, like Ricci and sectional  folds, M compact and oriented, and let u : M −→
            curvatures. However, it does not use these ideas  N be a smooth map. We can write the energy
            in real-world image-processing tasks, so there is  functional of u as:
                                                                                  Z
            a gap between theory and practice. On the other                     1          2
                                                                         E(u) =       | du | dvol g ,     (1)
            hand, our manuscript addresses this limitation by                   2  M
            proposing the 2-tension field (α = 2) as a novel              2
                                                              where | du | is the norm of du with respect to
            operator for image processing at the intersection
                                                              the metrics on M and N, and dvol g is the volume
            of geometric theory and tangible applications. We
                                                              form on M. Critical points of E(u) are called har-
            use adaptive local gradient adjustments and fi-
                                                              monic maps, and they solve the Euler – Lagrange
            nite difference methods to discretize the 2-tension
                                                              equation:
            field. This works around the problems that tra-
            ditional operators (like Laplacian) have with be-             τ(u) := traceg∇du = 0,          (2)
            ing too smooth while keeping structural details.  where ∇ is the induced connection on the pull-
            In addition, our work analyzes advanced applica-  back bundle u −1 TN, trace g is the trace with re-
            tions like image denoising, edge preservation, and  spect to the metric g on M and τ(u) is the tension
            feature enhancement, which were not present in    field of u. Noting that the tension field measures
                                                                       7
            the literature. 9                                 the distance of u from a totally geodesic map. 5
                The rest of this paper is organized as follows:   Geometrically, the tension field describes the
            Section 2 gives a general description of the geome-  amount of unbalance or stress in the map u. This
            try of tension fields, generalizations of the geome-  reflects the dependence of how the geometry of
            try of tension fields, and there we introduce the α-  the domain manifold M interacts with the geom-
            tension field. It explores the mathematical under-  etry of the target manifold N. Specifically:
            pinnings of these concepts and their role in geo-      1. If τ(u) = 0. The mapping u is harmonic,
            metric variational problems. Section 3 discusses         that is, it satisfies the condition that min-
            the use of tension fields to handle certain prob-        imizes the energy functional, so that the
            lems in image processing, including edge detec-          tension is balanced at all points. 5
            tion, denoising, and local contrast enhancement.       2. The points where τ(u) ̸= 0 represent the
            Section 4 is devoted to the utility of the α-tension     regions where the map is either stretch-
            field τ α (I) in image processing, emphasizing its       ing or compressing excessively. These ar-
            benefits in denoising, edge preservation, and fea-       eas typically correspond to locations with
            ture enhancement over conventional approaches.           high curvature or substantial variations in
            This leads us to Section 5, where the tension field      the mapping. 4
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