The effect of Laplacian filter in adaptive unsharp masking for infrared image enhancement

Jane, Onur
İlk Dağ, Özlem
Image processing, in particular image enhancement techniques have been the focal point of considerable research activity in the last decade. With the aid of an existing image enhancement technique, adaptive unsharp masking (AUM), we propose a novel kernel to be used in AUM filtering in order to enhance discontinuities which occur on the edges of targets of interest in infrared (IR) images. The proposed method uses an adaptive filter approach where an objective function is minimized by using descent algorithms. The output IR image has better sharpness and contrast adjustment for the detection of targets in terms of objective quality metrics. Hence, the proposed method ensures that the edges of the targets in IR images are sharper and that the quality of contrast adjustment has its optimum level in terms of peak signal-to-noise ratios.


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Kara, A. Onur; Okman, O. Erman; Aytac, Tayfun (Elsevier BV, 2011-09-01)
Most of the techniques developed for infrared (IR) image enhancement (IE) depend heavily on the scene, environmental conditions, and the properties of the imaging system. So, with a set of predefined scenario properties, a content-based IR-IE technique can be developed for better situational awareness. This study proposes an adaptive IR-IE technique based on clustering of wavelet coefficients of an image for sea surveillance systems. Discrete wavelet transform (DWT) of an image is computed and feature vecto...
The nonlinear and saturable absorption characteristics of Ga0.90In0.10Se and Ga0.85In0.15Se semiconductor crystals and their amorphous thin films
KARATAY, AHMET; Aksoy, Cagla; YAĞLIOĞLU, HALİME GÜL; ELMALI, Ayhan; Kurum, Ulas; ATEŞ, AYTÜNÇ; Hasanlı, Nızamı (IOP Publishing, 2011-07-01)
We investigated the nonlinear and saturable absorption characteristics of Ga0.90In0.10Se and Ga0.85In0.15Se semiconductor crystals and their very thin amorphous films by open aperture (OA) Z-scan and pump-probe techniques. The linear absorption spectra indicated a blue shift in energy with increasing film thickness. This can be attributed to the quantum confinement effect. For both 4 ns and 65 ps pulse durations the two photon absorption coefficients of Ga0.90In0.10Se and Ga0.85In0.15Se crystals increased w...
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Eker, S. U.; Arslan, Y.; Beşikci, Cengiz (Elsevier BV, 2011-05-01)
Quantum well infrared photodetector (QWIP) technology has allowed the realization of low cost staring focal plane arrays (FPAs). However, AlGaAs/(In)GaAs QWIP FPAs suffer from low quantum and conversion efficiencies under high frame rate and/or low background conditions.
Investigation of band gap energy versus temperature for SnS 2 thin films grown by RF-magnetron sputtering
Isik, M.; Gullu, H. H.; Terlemezoglu, M.; Surucu, O. Bayrakli; Parlak, Mehmet; Hasanlı, Nızamı (Elsevier BV, 2020-08-01)
SnS2 thin films grown by magnetron sputtering technique were characterized by structurally and optically in the present work. Crystalline parameters, atomic compositions, and surface characteristics of SnS2 thin films were presented according to results of applied structural techniques. Optical studies of SnS2 thin films were accomplished by Raman spectroscopy and transmission methods. Raman spectrum exhibited two modes around 198 and 320 cm−1. Transmittance data obtained for various temperatures between 10...
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Ata, Yalcin (The Optical Society, 2019-09-01)
Average channel capacity of free space optical (FSO) communication systems using a Gaussian beam with the intensity modulation and direct detection technique is investigated in anisotropic non-Kolmogorov strong turbulent atmosphere. The channel model is selected as gamma-gamma distribution, which is valid for strong turbulence. Obtained results show that anisotropy in both the horizontal and vertical affects the average channel capacity of an FSO communication system positively. Average channel capacity inc...
Citation Formats
H. G. İLK, O. Jane, and Ö. İlk Dağ, “The effect of Laplacian filter in adaptive unsharp masking for infrared image enhancement,” INFRARED PHYSICS & TECHNOLOGY, pp. 427–438, 2011, Accessed: 00, 2020. [Online]. Available: