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A linearization-based hybrid approach for 3D reconstruction of objects in a single image

Kotan Muhammed, Öz Cemil, Kahraman Abdulgani

International Journal of Applied Mathematics and Computer Science

2021

Vol. 31, no. 3

501--513

The shape-from-shading (SFS) technique uses the pattern of shading in images in order to obtain 3D view information. By virtue of their ease of implementation, linearization-based SFS algorithms are frequently used in the literature. In this study, Fourier coefficients of central differences obtained from gray-level images are employed, and two basic linearization-based algorithms are combined. By using the functionally generated surfaces and 3D reconstruction datasets, the hybrid algorithm is compared with linearization-based approaches. Five different evaluation metrics are applied on recovered depth maps and the corresponding gray-level images. The results on defective sample surfaces are also included to show the effect of the algorithm on surface reconstruction. The proposed method can prevent erroneous estimates on object boundaries and produce satisfactory 3D reconstruction results in a low number of iterations.

A perspective shape-from-shading metod using fast sweeping numerical scheme

Yang L., Han J.

Optica Applicata

2008

Vol. 38, nr 2

387-398

Shape-from-shading (SFS) is an approach of 3-D shape reconstruction from only one image. A new perspective SFS method is proposed in this paper. Firstly, a reflectance map equation under perspective projection is introduced. Then, the reflectance map equation turns into a static Hamilton-Jacobi equation. So the SFS problem is formulated as a viscosity solution of the static Hamilton-Jacobi equation. The fast sweeping numerical method is used to solve the Hamilton-Jacobi equation and a new SFS method is gained. At last, experiments on both synthetic and real images are given. Experiments on the synthetic image show that the proposed SFS method is fast and accurate. Results of the real image show the efficiency of the proposed method when dealing with complicated real surface, and new criteria to evaluate the performance of the method are proposed.

Automatic technique for superficial defects identification in metal patches. An automatic system for the identification of superficial defects

Niola V., Longobardo A., Longobardi M.

Applied Mechanics and Engineering

1999

Vol. 4, no 1

121-131

We have worked out an innovative system for the identification of superficial defects in low critical metallic patches. In a few seconds we reconstruct, using the fundamental principles of shape from shading, the third dimension of a digitized image, thanks to which we can identify the presence of a defect. Testing shows that the results achieved are more than satisfactory also in relation to the good rejection of the noises from the algorithm. Moreover we propose the advantages of using this system in an industrial field, and the conditions to be verified in industry in order to be able to test this technique.