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Nonlinear image processing with α-Tension field: A geometric approach






























                    Figure 1. The image on the left is the original, whereas the image on the right demonstrates
                    the effect of the tension field on the original image.


            Algorithm 1 Tension field algorithm for Figure 1  first one (the region) is a geometric insight that
                                                              can be used to more advanced image-parser tech-
              1: procedure TensionField(Image)
                                                              niques. Domains for tension fields allow a natural
              2:   Input:    Image (2D array), Output:
                                                              connection between geometry, mathematics, and
                Result
                                                              optimization, which can be exploited for the de-
              3:   Initialize Result with zeros, same size as
                                                              sign of advanced image processing tools like edge
                Image
                                                            preserving, smoothing, and shape extraction.
                               0   1  0
              4:   Kernel ← 1 −4 1      
                             
                               0   1  0                       4. Application of α−tension field in
              5:   for i = 1 to rows − 2 do                      image processing
              6:       for j = 1 to cols − 2 do               This section aims to investigate and emphasizes
              7:          Sum ← 0
                                                              the innovative aspects of the α-tension field as an
              8:          for m = 0 to 2 do
                                                              operator in image processing, defined by:
              9:             for n = 0 to 2 do                                           2 α−2            2
             10:                Sum += Kernel[m][n] ×          τ α (I) : = (α − 1)(1+ | ∇I | )  ∇I(∇ | ∇I | )
                                                                                  2 α−1
                Image[i − 1 + m][j − 1 + n]                           + (1+ | ∇I | )   ∆(I),             (15)
             11:             end for
                                                              with a specific focus on the case where α = 2. For
             12:          end for
                                                              this particular value, the equation simplifies to:
             13:          Result[i][j] ← Sum
                                                                                 2
                                                                                                    2
             14:       end for                                  τ 2 (I) = (1+ | ∇I | )∆I + ∇I(∇ | ∇I | ). (16)
             15:   end for                                    In the remainder of this paper, the term τ 2 (I) will
             16:   return Result                              be referred to as the 2-tension field.
             17: end procedure
                                                                  The 2-tension field is innovative because it
                                                              possesses an architectural design that enables the
                The algorithm used in Figure 1 to apply the   trade-off between noise suppression and preserva-
            tension field and demonstrate its effect is pre-  tion of essential image characteristics (like edges,
            sented in Algorithm 1. This algorithm outlines    textures, or fine details).  Unlike traditional
            the steps involved in computing the tension field  methods like total variation regularization or
            and illustrates how it is applied to achieve the  anisotropic diffusion, which get compromised by
            desired outcome depicted in Figure 1.             the staircasing effect or by oversimplifying the
                As we have seen in this section, the tension  gradients of structural complexity, this field is
            field is the fundamental concept in the study     capable of incorporating higher- order statistics
                                                                                            2
            of mappings between Riemannian manifolds and      through the term ∇I(∇ | ∇I | ). Such adapta-
            finds many applications in image processing. The  tion enables the model to respond to variations in
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