40,867 research outputs found
Natural images from the birthplace of the human eye
Here we introduce a database of calibrated natural images publicly available
through an easy-to-use web interface. Using a Nikon D70 digital SLR camera, we
acquired about 5000 six-megapixel images of Okavango Delta of Botswana, a
tropical savanna habitat similar to where the human eye is thought to have
evolved. Some sequences of images were captured unsystematically while
following a baboon troop, while others were designed to vary a single parameter
such as aperture, object distance, time of day or position on the horizon.
Images are available in the raw RGB format and in grayscale. Images are also
available in units relevant to the physiology of human cone photoreceptors,
where pixel values represent the expected number of photoisomerizations per
second for cones sensitive to long (L), medium (M) and short (S) wavelengths.
This database is distributed under a Creative Commons Attribution-Noncommercial
Unported license to facilitate research in computer vision, psychophysics of
perception, and visual neuroscience.Comment: Submitted to PLoS ON
Design Of Neural Network Circuit Inside High Speed Camera Using Analog CMOS 0.35 ÂĽm Technology
Analog VLSI on-chip learning Neural Networks represent a mature technology for a large number of applications involving industrial as well as consumer appliances. This is particularly the case when low power consumption, small size and/or very high speed are required. This approach exploits the computational features of Neural Networks, the implementation efficiency of analog VLSI circuits and the adaptation capabilities of the on-chip learning feedback schema. High-speed video cameras are powerful tools for investigating for instance the biomechanics analysis or the movements of mechanical parts in manufacturing processes. In the past years, the use of CMOS sensors instead of CCDs has enabled the development of high-speed video cameras offering digital outputs , readout flexibility, and lower manufacturing costs. In this paper, we propose a high-speed smart camera based on a CMOS sensor with embedded Analog Neural Network
General Defocusing Particle Tracking: fundamentals and uncertainty assessment
General Defocusing Particle Tracking (GDPT) is a single-camera,
three-dimensional particle tracking method that determines the particle depth
positions from the defocusing patterns of the corresponding particle images.
GDPT relies on a reference set of experimental particle images which is used to
predict the depth position of measured particle images of similar shape. While
several implementations of the method are possible, its accuracy is ultimately
limited by some intrinsic properties of the acquired data, such as the
signal-to-noise ratio, the particle concentration, as well as the
characteristics of the defocusing patterns. GDPT has been applied in different
fields by different research groups, however, a deeper description and analysis
of the method fundamentals has hitherto not been available. In this work, we
first identity the fundamental elements that characterize a GDPT measurement.
Afterwards, we present a standardized framework based on synthetic images to
assess the performance of GDPT implementations in terms of measurement
uncertainty and relative number of measured particles. Finally, we provide
guidelines to assess the uncertainty of experimental GDPT measurements, where
true values are not accessible and additional image aberrations can lead to
bias errors. The data were processed using DefocusTracker, an open-source GDPT
software. The datasets were created using the synthetic image generator
MicroSIG and have been shared in a freely-accessible repository
Research Pattern Classification using imaging techniques for Infarct and Hemorrhage Identification in the Human Brain
Medical Image analysis and processing has great
significance in the field of medicine, especially in Non-
invasive treatment and clinical study. Medical imaging
techniques and analysis tools enable the Doctors and
Radiologists to arrive at a specific diagnosis. Medical Image
Processing has emerged as one of the most important tools
to identify as well as diagnose various disorders. Imaging
helps the Doctors to visualize and analyze the image for
understanding of abnormalities in internal structures. The
medical images data obtained from Bio-medical Devices
which use imaging techniques like Computed Tomography
(CT), Magnetic Resonance Imaging (MRI) and
Mammogram, which indicates the presence or absence of
the lesion along with the patient history, is an important
factor in the diagnosis. The algorithm proposes the use of
Digital Image processing tools for the identification of
Hemorrhage and Infarct in the human brain, by using a
semi-automatic seeded region growing algorithm for the
processing of the clinical images. The algorithm has been
extended to the Real-Time Data of CT brain images and
uses an intensity-based growing technique to identify the
infarct and hemorrhage affected area, of the brain. The
objective of this paper is to propose a seeded region
growing algorithm to assist the Radiologists in identifying
the Hemorrhage and Infarct in the human brain and to arrive
at a decision faster and accurate.¢Lp¤
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