scholarly journals Both 3D Orientation and Local Contrast Affect Surface Lightness

2012 ◽  
Vol 12 (9) ◽  
pp. 1215-1215
Author(s):  
T. Y. Lee ◽  
D. H. Brainard
Keyword(s):  
Local Contrast ◽  
Surface Lightness

Merging of electron-diffraction intensities acquired with a slow-scan CCD camera of crotoxin complex crystals to 3.5Å resolution

1994 ◽  
Vol 52 ◽  
pp. 104-105
Author(s):  
Jaap Brink ◽  
Wah Chiu
Keyword(s):  
Electron Diffraction ◽  
Ccd Camera ◽  
Crystal Thickness ◽  
Local Contrast ◽  
Camera Model ◽  
Data Set ◽  
3 Dimensional ◽  
Diffraction Mode ◽  
Diffraction Patterns ◽  
Complex Crystals

Crotoxin complex is the principal neurotoxin of the South American rattlesnake, Crotalus durissus terrificus and has a molecular weight of 24 kDa. The protein is a heterodimer with subunit A assigneda chaperone function. Subunit B carries the lethal activity, which is exerted on both sides ofthe neuro-muscular junction, and which is thought to involve binding to the acetylcholine receptor. Insight in crotoxin complex’ mode of action can be gained from a 3 Å resolution structure obtained by electron crystallography. This abstract communicates our progress in merging the electron diffraction amplitudes into a 3-dimensional (3D) intensity data set close to completion. Since the thickness of crotoxin complex crystals varies from one crystal to the other, we chose to collect tilt series of electron diffraction patterns after determining their thickness. Furthermore, by making use of the symmetry present in these tilt data, intensities collected only from similar crystals will be merged.Suitable crystals of glucose-embedded crotoxin complex were searched for in the defocussed diffraction mode with the goniometer tilted to 55° of higher in a JEOL4000 electron cryo-microscopc operated at 400 kV with the crystals kept at -120°C in a Gatan 626 cryo-holder. The crystal thickness was measured using the local contrast of the crystal relative to the supporting film from search-mode images acquired using a 1024 x 1024 slow-scan CCD camera (model 679, Gatan Inc.).

scholarly journals Underwater Image Enhancement Based on Local Contrast Correction and Multi-Scale Fusion

2021 ◽  
Vol 9 (2) ◽  
pp. 225
Author(s):  
Farong Gao ◽  
Kai Wang ◽  
Zhangyi Yang ◽  
Yejian Wang ◽  
Qizhong Zhang
Keyword(s):  
Image Enhancement ◽  
Local Contrast ◽  
Fusion Method ◽  
Formation Model ◽  
Low Contrast ◽  
White Balance ◽  
Multi Scale ◽  
Color Distortion ◽  
Underwater Image ◽  
Enhancement Method

In this study, an underwater image enhancement method based on local contrast correction (LCC) and multi-scale fusion is proposed to resolve low contrast and color distortion of underwater images. First, the original image is compensated using the red channel, and the compensated image is processed with a white balance. Second, LCC and image sharpening are carried out to generate two different image versions. Finally, the local contrast corrected images are fused with sharpened images by the multi-scale fusion method. The results show that the proposed method can be applied to water degradation images in different environments without resorting to an image formation model. It can effectively solve color distortion, low contrast, and unobvious details of underwater images.

scholarly journals Clinical evaluation of ‘local contrast enhancement’ for oral fluorescein angiograms

Eye ◽  
2000 ◽  
Vol 14 (3) ◽  
pp. 318-318 ◽  
Author(s):  
Richard S B Newsom ◽  
Chanjira Sinthanayothin ◽  
James Boyce ◽  
Anthony G Casswell ◽  
Tom H Williamson
Keyword(s):  
Contrast Enhancement ◽  
Clinical Evaluation ◽  
Local Contrast ◽  
Local Contrast Enhancement

Local Contrast in Natural Images: Normalisation and Coding Efficiency

Perception ◽  
10.1068/p2996 ◽  
2000 ◽  
Vol 29 (9) ◽  
pp. 1041-1055 ◽  
Author(s):  
Nuala Brady ◽  
David J Field
Keyword(s):  
Natural Images ◽  
Local Contrast ◽  
Coding Efficiency

Global brightness and local contrast adaptive enhancement for low illumination color image

Optik ◽  
2014 ◽  
Vol 125 (6) ◽  
pp. 1795-1799 ◽  
Author(s):  
Zhigang Zhou ◽  
Nong Sang ◽  
Xinrong Hu
Keyword(s):  
Color Image ◽  
Local Contrast ◽  
Adaptive Enhancement ◽  
Low Illumination

Image Sharpness and Contrast Tuning in the Early Visual Pathway

2017 ◽  
Vol 27 (08) ◽  
pp. 1750045 ◽  
Author(s):  
Eduardo Sánchez ◽  
Rubén Ferreiroa ◽  
Adrián Arias ◽  
Luis M. Martínez
Keyword(s):  
Functional Organization ◽  
Ganglion Cells ◽  
Receptive Fields ◽  
Local Contrast ◽  
Retinal Ganglion ◽  
Image Sharpness ◽  
Image Processing Techniques ◽  
Thalamic Relay ◽  
Processing Techniques

The center–surround organization of the receptive fields (RFs) of retinal ganglion cells highlights the presence of local contrast in visual stimuli. As RF of thalamic relay cells follow the same basic functional organization, it is often assumed that they contribute very little to alter the retinal output. However, in many species, thalamic relay cells largely outnumber their retinal inputs, which diverge to contact simultaneously several units at thalamic level. This gain in cell population as well as retinothalamic convergence opens the door to question how information about contrast is transformed at the thalamic stage. Here, we address this question using a realistic dynamic model of the retinothalamic circuit. Our results show that different components of the thalamic RF might implement filters that are analogous to two types of well-known image processing techniques to preserve the quality of a higher resolution version of the image on its way to the primary visual cortex.

scholarly journals Measuring Streetscape Complexity Based on the Statistics of Local Contrast and Spatial Frequency

PLoS ONE ◽  
2014 ◽  
Vol 9 (2) ◽  
pp. e87097 ◽  
Author(s):  
André Cavalcante ◽  
Ahmed Mansouri ◽  
Lemya Kacha ◽  
Allan Kardec Barros ◽  
Yoshinori Takeuchi ◽  
...  
Keyword(s):  
Spatial Frequency ◽  
Local Contrast
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