Search results for "Digital image"

<title>Photonic vascular diagnostics by four-channel photoplethysmography</title>

2005

A four-channel photoplethysmography device was designed and built at University of Latvia to detect signals from different body parts and to analyze the signal shapes. The device consists of optical contact probes, interface, and a standard PC. Clinical tests were performed with occlusion patients having vascular problems at arm or leg arteries. Results showed significant difference in the pulse wave transit time in occluded and nonoccluded part of the body.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Multichannel single-output color pattern recognition by use of a joint-transform correlator.

1996

A novel method for performing color image recognition by the use of the coherent joint-transform correlator is introduced. The input plane of the proposed method is a spatial rearrangement of the separation into color channels of both the color input scene and the color target. This input plane is gray scaled and monochromatic, thus it can be displayed by the use of amplitude spatial light modulators to achieve real-time operation. The system provides a single output-plane result of the optical coherent addition of the separate channels’ correlation outputs. At the output plane no electronic postprocessing is needed, and the detection decision is achieved simply by the application of thresh…

Multi-channel chromatic transformations for nonlinear color pattern recognition

2002

We present a new approach for color pattern recognition based on multi-channel nonlinear correlations. High discrimination capability is obtained in comparison with common linear multi-channel detection methods. We apply the nonlinear morphological correlation to different color channel decompositions as RGB and ATD channels. Moreover, in order to improve the discrimination we have introduced a new color transformation. When a high selectivity is required, the combination of the nonlinear correlation and the new color decomposition yields to detect the object using just a single channel. Simulation results are provided.

Experimental investigation on the effectiveness of basalt-fibre strengthening systems for confining masonry elements

L’impiego di materiali compositi per il rinforzo di colonne in muratura è diventato una pratica ampiamente diffusa nel corso degli ultimi decenni. Questa tecnica, che consiste generalmente nell’applicazione di materiali polimerici fibrorinforzati (Fibre Reinforced Polymer-FRP), ha mostrato buone potenzialità, essendo in grado di garantire notevoli incrementi di resistenza e duttilità dell’elemento rinforzato, grazie ad un’azione di confinamento passivo. Tuttavia, l’impiego di compositi a matrice polimerica presenta alcuni limiti legati soprattutto alle prestazioni delle resine epossidiche, che a causa della loro natura sintetica danno luogo a problemi di compatibilità con il supporto murari…

Use of wavelet for image processing in smart cameras with low hardware resources

2013

International audience; Images from embedded sensors need digital processing to recover high-quality images and to extract features of a scene. Depending on the properties of the sensor and on the application, the designer fits together different algorithms to process images. In the context of embedded devices, the hardware supporting those applications is very constrained in terms of power consumption and silicon area. Thus, the algorithms have to be compliant with the embedded specifications i.e. reduced computational complexity and low memory requirements. We investigate the opportunity to use the wavelet representation to perform good quality image processing algorithms at a lower compu…

Unmanned Aerial Vehicle-Based Non Destructive Diagnostics

2018

The paper proposes a cloud platform for analyzing the radiometric infrared videos uploaded by drones which patrol large photovoltaic plants. Thanks to artificial vision algorithms, it does not require any human support to select and associate the framed PV modules to the corresponding ones in the topology of the photovoltaic plant. The algorithm implements an innovative diagnostic protocol, which evaluates the thermal state of the photovoltaic module, whichever the environmental conditions are. The data automatically computed and collected in a multimedia database provide the O&M technicians with significant information to monitor the ageing of each module of the photovoltaic plant. The pro…

Image Inpainting Methods Evaluation and Improvement

2014

With the upgrowing of digital processing of images and film archiving, the need for assisted or unsupervised restoration required the development of a series of methods and techniques. Among them, image inpainting is maybe the most impressive and useful. Based on partial derivative equations or texture synthesis, many other hybrid techniques have been proposed recently. The need for an analytical comparison, beside the visual one, urged us to perform the studies shown in the present paper. Starting with an overview of the domain, an evaluation of the five methods was performed using a common benchmark and measuring the PSNR. Conclusions regarding the performance of the investigated algorith…

Change-driven Image Architecture on FPGA with adaptive threshold for Optical-Flow Computation

2006

Optical flow computation has been extensively used for object motion estimation in image sequences. However, the results obtained by most optical flow techniques are as accurate as computationally intensive due to the large amount of data involved. A new strategy for image sequence processing has been developed; pixels of the image sequence that significantly change fire the execution of the operations related to the image processing algorithm. The data reduction achieved with this strategy allows a significant optical flow computation speed-up. Furthermore, FPGAs allow the implementation of a custom data-flow architecture specially suited for this strategy. The foundations of the change-dr…

Perceptual Image Representations for Support Vector Machine Image Coding

2007

Support-vector-machine image coding relies on the ability of SVMs for function approximation. The size and the profile of the e-insensitivity zone of the support vector regressor (SVR) at some specific image representation determines (a) the amount of selected support vectors (the compression ratio), and (b) the nature of the introduced error (the compression distortion). However, the selection of an appropriate image representation is a key issue for a meaningful design of the e-insensitivity profile. For example, in image-coding applications, taking human perception into account is of paramount relevance to obtain a good rate-distortion performance. However, depending on the accuracy of t…

BioImageXD - Free Microscopy Image Processing Software

2008

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008