FOURIER TRANSFORM METHODS IN IMAGE ANALYSIS OF COMPRESSION WOOD AT THE CELLULAR LEVEL

IAWA Journal ◽  
2004 ◽  
Vol 25 (3) ◽  
pp. 311-324 ◽  
Author(s):  
Mattias K. Moëll ◽  
Minoru Fujita
Keyword(s):  
Fourier Transform ◽  
Compression Wood ◽  
Image Data ◽  
Cellular Level ◽  
Normal Wood ◽  
Two Dimensional ◽  
One Dimensional ◽  
Two Dimensional Image ◽  
Microscopic Features

Compression wood affects the overall quality of construction timber and paper quality. We have investigated the microscopic features of lumen shape and tracheid shape for compression wood studies and detection in softwoods. In this paper, we describe a method for directly analyzing tracheid and lumen shape over an entire image. The method uses the Fast Fourier Transform (FFT) and reduces the two-dimensional image data to one-dimensional data, from which lumen and tracheid shape can be evaluated. We illustrate the method by comparison of compression wood images to normal wood images. The results of detecting severe compression wood were successful, while the detection of weak compression wood was not satisfactory.

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

scholarly journals Measurement Matrix Optimization via Mutual Coherence Minimization for Compressively Sensed Signals Reconstruction

2020 ◽  
Vol 2020 ◽  
pp. 1-18
Author(s):  
Ziran Wei ◽  
Jianlin Zhang ◽  
Zhiyong Xu ◽  
Yong Liu ◽  
Krzysztof Okarma
Keyword(s):  
Optimization Methods ◽  
Superior Performance ◽  
Gram Matrix ◽  
Sparse Signals ◽  
Two Dimensional ◽  
Measurement Matrix ◽  
Mutual Coherence ◽  
One Dimensional ◽  
Two Dimensional Image ◽  
Matrix Optimization

For signals reconstruction based on compressive sensing, to reconstruct signals of higher accuracy with lower compression rates, it is required that there is a smaller mutual coherence between the measurement matrix and the sparsifying matrix. Mutual coherence between the measurement matrix and sparsifying matrix can be expressed indirectly by the property of the Gram matrix. On the basis of the Gram matrix, a new optimization algorithm of acquiring a measurement matrix has been proposed in this paper. Firstly, a new mathematical model is designed and a new method of initializing measurement matrix is adopted to optimize the measurement matrix. Then, the loss function of the new algorithm model is solved by the gradient projection-based method of Gram matrix approximating an identity matrix. Finally, the optimized measurement matrix is generated by minimizing mutual coherence between measurement matrix and sparsifying matrix. Compared with the conventional measurement matrices and the traditional optimization methods, the proposed new algorithm effectively improves the performance of optimized measurement matrices in reconstructing one-dimensional sparse signals and two-dimensional image signals that are not sparse. The superior performance of the proposed method in this paper has been fully tested and verified by a large number of experiments.

scholarly journals Determination of hard X-ray polarization from two-dimensional images

2020 ◽  
Vol 53 (6) ◽  
pp. 1559-1561
Author(s):  
Robert B. Von Dreele ◽  
Wenqian Xu
Keyword(s):  
Incident Beam ◽  
Beam Polarization ◽  
Two Dimensional ◽  
One Dimensional ◽  
X Ray ◽  
Dimensional Image ◽  
Two Dimensional Image ◽  
The Difference ◽  
Two Dimensional Images

An estimate of synchrotron hard X-ray incident beam polarization is obtained by partial two-dimensional image masking followed by integration. With the correct polarization applied to each pixel in the image, the resulting one-dimensional pattern shows no discontinuities arising from the application of the mask. Minimization of the difference between the sums of the masked and unmasked powder patterns allows estimation of the polarization to ±0.001.

Multichannel Fourier Transform Spectroscopy Using Two-Dimensional Detection of the Interferogram and its Application to Raman Spectroscopy

1993 ◽  
Vol 47 (7) ◽  
pp. 863-868 ◽  
Author(s):  
Satoshi Takahashi ◽  
Jeung Sun Ahn ◽  
Shuji Asaka ◽  
Teizo Kitagawa
Keyword(s):  
Fourier Transform ◽  
Fringe Pattern ◽  
Principal Axis ◽  
Monochromatic Light ◽  
Fourier Transform Spectroscopy ◽  
Present System ◽  
The Novel ◽  
Two Dimensional ◽  
One Dimensional ◽  
Ccd Detector

A system for multichannel Fourier transform spectroscopy was constructed by using a CCD detector and an interferometer consisting of Savart plate held between two polarizers, and practical problems associated with its application to Raman experiments were investigated. The novel idea of the present system lies in avoiding the aliasing distortion, seen in the spectrum measured with a one-dimensional multichannel detector, by arranging the principal axis of the sensitized plane of the CCD detector so that it is not coincident with the direction of the fringe pattern of the interferogram. The observed interferogram suffered geometrical distortion due to incompleteness of the Savart plate. In order to circumvent this problem, an algorithm for correcting this distortion by referring to the interferogram of appropriate monochromatic light was successfully developed. The resolution of a Raman spectrum obtained for indene was ∼40 cm−1, in agreement with the theoretical value expected for this system.

Person Localization System Using Privacy-Preserving Sensor

2011 ◽  
Vol 103 ◽  
pp. 622-627 ◽  
Author(s):  
Shota Nakashima ◽  
Hui Min Lu ◽  
Kohei Miyata ◽  
Yuhki Kitazono ◽  
Serikawa Seiichi
Keyword(s):  
Low Cost ◽  
Video Camera ◽  
Brightness Distribution ◽  
Privacy Preserving ◽  
Two Dimensional ◽  
Texture Image ◽  
Localization System ◽  
One Dimensional ◽  
Two Dimensional Image ◽  
Simulation Results

A privacy-preserving sensor for person localization has been developed. In theory, the sensor can be constructed with a line sensor and cylindrical lens because only a one-dimensional brightness distribution is needed. However, a line sensor is expensive. In contrast, CMOS area sensors are low cost and are increasing in sensitivity according to recent rapid advancement in the technology. Therefore, we covered the CMOS area sensor physically so that it behaved as a line sensor, we substituted CMOS sensors for the line sensors in practice. The proposed sensor obtains a one-dimensional horizontal brightness distribution that is approximately equal to the integration value of each vertical pixel line of the two-dimensional image. It is impossible to restore the two-dimensional detail texture image from one-dimensional brightness distribution, although it obtains enough information to detect a person’s position and movement status. Thus, the privacy is protected. Moreover, the appearance of the proposed sensor is very different from the conventional video camera, so the psychological resistance of having a picture taken is reduced. In this work, we made the privacy preserving sensor practically, and verified whether a person’s state was able to be detected. The simulation results show that the proposed sensor can detect a present person’s state responsively without violating privacy.

Well-controlled silver nanowire/graphene hybrid from full solution process

2016 ◽  
Vol 51 (8) ◽  
pp. 1149-1154 ◽  
Author(s):  
Jeong Eon Park ◽  
Dong Hack Suh
Keyword(s):  
Mass Production ◽  
Silver Nanowires ◽  
Solution Process ◽  
Silver Nanowire ◽  
Ultrasonic Power ◽  
Two Dimensional ◽  
One Dimensional ◽  
Conductive Materials ◽  
Full Solution

The surface of a one-dimensional silver nanowire was covered with amphiphilic materials, N-(2-aminoethyl)-3a-hydroxy-5b-cholan-24-amide, and patched with two-dimensional graphene to form individually controlled hybrid. Graphene was prepared from ultrasonic in o-dichlorobenzene without any additives. As N-(2-aminoethyl)-3a-hydroxy-5b-cholan-24-amide between silver nanowires and graphene tightly held each other, silver nanowire was individually covered with graphene without introducing ultrasonic power, the necessary process to evenly mix silver nanowires and graphene but lead to damage and oxidize silver nanowires. Although the quality of graphene was inferior, the properties of hybrid were superior compared with pristine silver nanowire/graphene except introducing N-(2-aminoethyl)-3a-hydroxy-5b-cholan-24-amide. All processes to form the hybrid were carried out in solution. Therefore, this makes the processes less expensive and more useful and opens up opportunities for the mass production for conductive materials.

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