Studies on Automatic Recognition System of Fabric Weaves’ Parameters

2011 ◽  
Vol 341-342 ◽  
pp. 829-832 ◽  
Author(s):  
Yan Mei Li ◽  
Xiao Kun Qiu ◽  
Zhen Zhen Jiang
Keyword(s):  
Fourier Transform ◽  
Power Spectrum ◽  
Computer Image ◽  
Recognition System ◽  
Automatic Recognition ◽  
Image Process ◽  
Two Dimensional ◽  
Process Technology ◽  
Weave Pattern ◽  
In Virtue Of

In virtue of having some periodicity in space, the fabric weave pattern can be recognized by using computer image process technology. Firstly, the reflected image and transmissive image of fabric were scanned and disposed. Then its image of two-dimensional power spectrum and image of autocorrelation were obtained by means of Fourier transform technology. Finally the fabric weave parameters can be calculated, including density of warp and weft, the size of warp and weft and the yarn numbers of weave repetition etc. Based on foregoing theory, this paper develops automatic recognition system of fabric weave parameters, which is worth of popularizing.

Two-Dimensional Fast Fourier Transform and Power Spectrum for Surface Roughness in three Dimensions

1995 ◽  
Vol 209 (5) ◽  
pp. 381-391 ◽  
Author(s):  
W P Dong ◽  
K J Stout
Keyword(s):  
Surface Roughness ◽  
Fourier Transform ◽  
Power Spectrum ◽  
Fast Fourier Transform ◽  
Surface Characterization ◽  
Three Dimensions ◽  
Two Dimensional ◽  
Comprehensive Understanding ◽  
Extract Information

Two-dimensional power spectrums of engineering surfaces contain plenty of information that is important and valuable for surface characterization. However, the characteristics of the two-dimensional spectrums are largely unknown and the algorithm to implement them is not familiar to many engineers or researchers. This paper describes a detailed procedure to implement the two-dimensional fast Fourier transform and power spectrum for surface roughness in three dimensions. Methods used to extract information from the spectrums are introduced. In order to perform two-dimensional spectral analysis and to have a comprehensive understanding of the characteristics of engineering surfaces, an atlas of the two-dimensional spectrums of representative engineering surfaces are presented. The properties of the spectrums are discussed in conjunction with theoretical analysis and visual characterization of the presented spectrums.

scholarly journals Fourier Analysis of Line-Profile Variations: Toward Stellar m – v Diagrams?

1993 ◽  
Vol 139 ◽  
pp. 148-148
Author(s):  
W.J. Merryfield ◽  
E.J. Kennelly
Keyword(s):  
Time Series ◽  
Fourier Transform ◽  
Power Spectrum ◽  
Spectral Line ◽  
Single Mode ◽  
Two Dimensional ◽  
Line Profiles ◽  
Azimuthal Position ◽  
Scuti Stars ◽  
Straightforward Interpretation

AbstractNumerous rapidly rotating δ Scuti stars exhibit variable line profiles containing traveling subfeatures [l]-[2], which may be signatures of nonradial pulsations having relatively high azimuthal order |m| We describe a procedure whereby a time series of spectral line profiles is Fourier analysed both in time and in a wavelength variable that is presumed to correspond to azimuthal position Φ on the star. What such an analysis can tell us is examined by analysing artificially-generated data. For an ideal example in which sin i = 1 and a single mode having is present, the two-dimensional Fourier transform yields a power spectrum in frequency and an apparent azimuthal order that provides a good indication of the actual and m. Such a straightforward interpretation is also possible when sin i < 1, and when multiple sectoral modes are present. For tesseral modes may correspond more closely to than to m.

Design of one-dimensional power spectrum using two-dimensional fast Fourier transform for discrimination of paper-based kraft tapes

2015 ◽  
Vol 257 ◽  
pp. 329-336 ◽  
Author(s):  
Sara Sasaoka ◽  
Koichi Saito ◽  
Kenjirou Higashi ◽  
Waree Limwikrant ◽  
Kunikazu Moribe ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Power Spectrum ◽  
Fast Fourier Transform ◽  
Two Dimensional ◽  
One Dimensional

Directional spectral analysis and filtering of geophysical maps

Geophysics ◽  
1988 ◽  
Vol 53 (12) ◽  
pp. 1587-1591 ◽  
Author(s):  
Freyr Thorarinsson ◽  
Stefan G. Magnusson ◽  
Axel Bjornsson
Keyword(s):  
Spectral Analysis ◽  
Fourier Transform ◽  
Power Spectrum ◽  
Two Dimensional ◽  
Directional Filtering ◽  
Gravity And Magnetic ◽  
The Fourier Transform ◽  
Map Data ◽  
Tectonic Features

The detection of linear anomalies in map data is facilitated by studying the two‐dimensional power spectrum, because the directivity of the energy in the map is preserved in the Fourier transform. The lineaments associated with individual peaks in the spectrum are then separated from the map data by directional filtering and studied independently of other map features. Gravity and magnetic maps from an active rift area in southwestern Iceland are analyzed in this manner. The agreement between the filtered maps is good and they fit the observed tectonic features quite well.

scholarly journals METHOD OF COMPUTER CONTROL OF TWISTED THREAD PARAMETERS FROM ITS IMAGE

2021 ◽  
Vol 4 (2(83)) ◽  
pp. 20-32
Author(s):  
P. Shlyakhtenko
Keyword(s):  
Fourier Transform ◽  
Diffraction Pattern ◽  
Computer Analysis ◽  
Computer Image ◽  
Computer Control ◽  
Geometric Parameters ◽  
Two Dimensional ◽  
Automatic Computer ◽  
Industrial Samples

A non-hardware method for computer control of the geometric parameters of a twisted thread using a two-dimensional Fourier transform program of its computer image is proposed. First, the program calculates the diffraction pattern from the investigated image of the thread. Then, the same program builds a diffraction pattern from the image of the first pattern, which does not contain speckles in the proposed method. This makes it possible to carry out its automatic computer analysis with the output to the digital values ​​of the calculated parameters. The effectiveness of the method is illustrated on model and industrial samples of synthetic threads.

Comparison of Calculated and Recorded Electron Energy-Loss Spectra of Aluminium and Carbon

1990 ◽  
Vol 48 (2) ◽  
pp. 64-65
Author(s):  
L. Reimer ◽  
R. Oelgeklaus
Keyword(s):  
Fourier Transform ◽  
Energy Loss ◽  
Electron Energy ◽  
Rotational Symmetry ◽  
Mean Free Path ◽  
Single Scattering ◽  
Specimen Thickness ◽  
Two Dimensional ◽  
Image Position ◽  
Electron Energy Loss

Quantitative electron energy-loss spectroscopy (EELS) needs a correction for the limited collection aperture α and a deconvolution of recorded spectra for eliminating the influence of multiple inelastic scattering. Reversely, it is of interest to calculate the influence of multiple scattering on EELS. The distribution f(w,θ,z) of scattered electrons as a function of energy loss w, scattering angle θ and reduced specimen thickness z=t/Λ (Λ=total mean-free-path) can either be recorded by angular-resolved EELS or calculated by a convolution of a normalized single-scattering function ϕ(w,θ). For rotational symmetry in angle (amorphous or polycrystalline specimens) this can be realised by the following sequence of operations :(1)where the two-dimensional distribution in angle is reduced to a one-dimensional function by a projection P, T is a two-dimensional Fourier transform in angle θ and energy loss w and the exponent -1 indicates a deprojection and inverse Fourier transform, respectively.

PERBANDINGAN METODE HOMOMORPHIC FILTERING DAN METODE CONTRAST STRECHING UNTUK PERBAIKAN KUALITAS CITRA UNDERWATER

2018 ◽  
Vol 2 (1) ◽  
Author(s):  
Adi Mora Lubis ◽  
Nelly Astuti Hasibuan ◽  
Imam Saputra
Keyword(s):  
Digital Image ◽  
Water Environment ◽  
Repair Process ◽  
Image Process ◽  
Two Dimensional ◽  
Two Dimensional Image ◽  
Underwater Image ◽  
Homomorphic Filtering ◽  
Contrast Stretching

Digital imagery is a two-dimensional image process through a digital computer that is used to manipulate and modify images in various ways. Photos are examples of two-dimensional images that can be processed easily. Each photo in the form of a digital image can be processed through a specific software. In the water environment, the light factor greatly influences the results of the quality of the image obtained. With the deepening of underwater shooting, the results obtained will be the darker the quality of the underwater image. . uneven lighting and bluish tones. One of the factors that influence the recognition results in pattern recognition is the quality of the image that is inputted. The image acquired from the source does not always have good quality. The process of repairing digital images that experience interference in lighting. The lighting repair process uses homomorphic filtering and uses contrast striching and will compare the quality of both methods and test to prove the results of image quality between homomorphic filtering and contrast streching. Until later the results of both methods can be seen which is better. homomorphic filtering and contrast stretching can produce image improvements with pretty good performance.Keywords: Digital Image, Underwater Image, Homomorphic Filtering, Contrast Streching, Matlab R2010a

IMPLEMENTASI METODE RETINEX UNTUK MENINGKATKAN KUALITAS CITRA UNDERWATER

2018 ◽  
Vol 2 (1) ◽  
Author(s):  
Bainun Harahap
Keyword(s):  
Water Environment ◽  
Repair Process ◽  
Image Process ◽  
Two Dimensional ◽  
Two Dimensional Image ◽  
Underwater Image ◽  
Object Search ◽  
Image Improvement ◽  
Underwater Object

Digital imagery is a two-dimensional image process through a digital computer that is used to manipulate and modify images in various ways. Photos are examples of two-dimensional images that can be processed easily. Each photo in the form of a digital image can be processed through certain software devices. In the water environment, light factors greatly influence the results of image quality obtained. With the deepening of underwater shooting, the results obtained will be the darker the quality of the underwater image. Underwater imagery is widely used as an object in various activities such as underwater habitat mapping, underwater environment monitoring, underwater object search. Uneven lighting and colors that tend to be bluish and runny. One of the factors that influence the recognition results in pattern recognition is the quality of the image that is inputted. The image acquired from the source does not always have good quality. The process of improvement in digital images that experience interference in lighting and exposure to sunlight. The lighting repair process uses the retinex method and will compare the quality of the two methods later. Until later the results of both methods can be seen which is better. Retinex method can produce image improvement with high performance.Keywords: Digital Cintra, Underwater, Matlab Retinex Method

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