Search results for "Grayscale"

Texture Synthesis for Digital Restoration in the Bit-Plane Representation

2007

In this paper we propose a new approach to handle the problem of restoration of grayscale textured images. The purpose is to recovery missing data of a damaged area. The key point is to decompose an image in its bit-planes, and to process bits rather than pixels. We propose two texture synthesis methods for restoration. The first one is a random generation process, based on the conditional probability of bits in the bit-planes. It is designed for images with stochastic textures. The second one is a best-matching method, running on each bit-plane, that is well suited to synthesize periodic patterns. Results are compared with a state-of-the-art restoration algorithm.

Decomposable multiphase entropic descriptor

2013

To quantify degree of spatial inhomogeneity for multiphase materials we adapt the entropic descriptor (ED) of a pillar model developed to greyscale images. To uncover the contribution of each phase we introduce the suitable 'phase splitting' of the adapted descriptor. As a result, each of the phase descriptors (PDs) describes the spatial inhomogeneity attributed to each phase-component. Obviously, their sum equals to the value of the overall spatial inhomogeneity. We apply this approach to three-phase synthetic patterns. The black and grey components are aggregated or clustered while the white phase is the background one. The examples show how the valuable microstuctural information related…

Estimation of orientation characteristic of fibrous material

2001

A new statistical method for estimating the orientation distribution of fibres in a fibre process is suggested where the process is observed in the form of a degraded digital greyscale image. The method is based on line transect sampling of the image in a few fixed directions. A well-known method based on stereology is available if the intersections between the transects and fibres can be counted. We extend this to the case where, instead of the intersection points, only scaled variograms of grey levels along the transects are observed. The nonlinear estimation equations for a parametric orientation distribution as well as a numerical algorithm are given. The method is illustrated by a real…

Color stabilizes textbook visual processing

2011

We report that pages with color illustrations elicit more homogeneous duration of fixations in 12 elementary school children. For six first graders, we compared the reading of the color cover and a greyscale illustrated text page of an abcbook. For six second grade pupils, we demonstrated a color and a greyscale fairytale book page. The fixations we recorded are concordant with the duration for preschoolers reported elsewhere. Average duration of fixations on a page with color elements are shorter than on greyscale ones, 425 (SE=13.4) and 461 (18.3) ms, respectively. The correlation analysis lends support that a color page is processed differently than its greyscale version. Fixation durati…

A nonlinear oscillators network devoted to image processing

2004

A contrast enhancement and image inverting tool using a lattice of uncoupled nonlinear oscillators is proposed. We show theoretically and numerically that the gray scale picture contrast is strongly enhanced even if this one is initially very small. An image inversion can be also obtained in real time with the same Cellular Nonlinear Network (CNN) without reconfiguration of the network. A possible electronic implementation of this CNN is finally discussed.

3D Displacements and Strains Solid Measurement based on the Surface Texture with a Scanner Laser

2013

International audience; The developments of non-contact measurement are today widely due to the unprecedented progress of optronic. The applications of these techniques are wide and varied for the 3D measurement of industrial products. In addition to the forms and dimensions, we show in this paper that the devices of laser scanning permit to measure displacements and deformations. In this case, it is necessary to follow a solid particle in its motion. It is then necessary to identify the particle between two configurations of the body before and after displacement. The method of greyscale patterns, obtained by applying a spray, is generally used. The originality of the proposed method is ba…

Strain fields measurement of non-rigid solid by scanning laser coupled with camera

2013

International audience; Abstract. Today, the techniques of measurement without contact by scanning laser are increasingly used. These techniques allow to measure 3D objects without contact and the measurement rates can reach few thousand points by second that is very adapted to complex shapes. To measure displacements and deformations, it is necessary to follow a solid particle in its motion between two configurations of the body before and after displacement. The method of stereovision based on grayscale patterns, obtained by applying a spray, is generally used. The results are obtained by two correlations: spatial and temporal correlations. An alternative method consists to use a scanner …

A Robust Multi Stage Technique for Image Binarization of Degraded Historical Documents

2017

International audience; Document image binarization is a central problem in many document analysis systems. Indeed, it represents one of the basic challenges, especially in case of historical documents analysis. In this paper, we propose a novel robust multi stage framework that combines different existing document image thresholding methods for the purpose of getting a better binarization result. CLAHE technique is introduced to significantly enhance contrast in some poor images. The proposed method then uses a hybrid algorithm to partition image into foreground and background. A special procedure is finally applied in order to remove small noise and correct characters morphology. Experime…

Randomized Hough Transform for Ellipse Detection with Result Clustering

2005

Our research is focused on the development of robust machine vision algorithms for pattern recognition. We want to provide robotic systems the ability to understand more on the external real world. In this paper, we describe a method for detecting ellipses in real world images using the randomized Hough transform with result clustering. A preprocessing phase is used in which real world images are transformed - noise reduction, greyscale transform, edge detection and final binarization - in order to be processed by the actual ellipse detector. The ellipse detector filters out false ellipses that may interfere with the final results. Due to the fact that usually more "virtual" ellipses are de…

2020

Abstract. Despite the availability of both commercial and open-source software, an ideal tool for digital rock physics analysis for accurate automatic image analysis at ambient computational performance is difficult to pinpoint. More often, image segmentation is driven manually, where the performance remains limited to two phases. Discrepancies due to artefacts cause inaccuracies in image analysis. To overcome these problems, we have developed CobWeb 1.0, which is automated and explicitly tailored for accurate greyscale (multiphase) image segmentation using unsupervised and supervised machine learning techniques. In this study, we demonstrate image segmentation using unsupervised machine le…