1,149 research outputs found
Spotting Separator Points at Line Terminals in Compressed Document Images for Text-line Segmentation
Line separators are used to segregate text-lines from one another in document
image analysis. Finding the separator points at every line terminal in a
document image would enable text-line segmentation. In particular, identifying
the separators in handwritten text could be a thrilling exercise. Obviously it
would be challenging to perform this in the compressed version of a document
image and that is the proposed objective in this research. Such an effort would
prevent the computational burden of decompressing a document for text-line
segmentation. Since document images are generally compressed using run length
encoding (RLE) technique as per the CCITT standards, the first column in the
RLE will be a white column. The value (depth) in the white column is very low
when a particular line is a text line and the depth could be larger at the
point of text line separation. A longer consecutive sequence of such larger
depth should indicate the gap between the text lines, which provides the
separator region. In case of over separation and under separation issues,
corrective actions such as deletion and insertion are suggested respectively.
An extensive experimentation is conducted on the compressed images of the
benchmark datasets of ICDAR13 and Alireza et al [17] to demonstrate the
efficacy.Comment: Line separators, Document image analysis, Handwritten text,
Compression and decompression, RLE, CCITT. Line separator points at every
line terminal in a compressed handwritten document images enabling text line
segmentatio
GLCM-based chi-square histogram distance for automatic detection of defects on patterned textures
Chi-square histogram distance is one of the distance measures that can be
used to find dissimilarity between two histograms. Motivated by the fact that
texture discrimination by human vision system is based on second-order
statistics, we make use of histogram of gray-level co-occurrence matrix (GLCM)
that is based on second-order statistics and propose a new machine vision
algorithm for automatic defect detection on patterned textures. Input defective
images are split into several periodic blocks and GLCMs are computed after
quantizing the gray levels from 0-255 to 0-63 to keep the size of GLCM compact
and to reduce computation time. Dissimilarity matrix derived from chi-square
distances of the GLCMs is subjected to hierarchical clustering to automatically
identify defective and defect-free blocks. Effectiveness of the proposed method
is demonstrated through experiments on defective real-fabric images of 2 major
wallpaper groups (pmm and p4m groups).Comment: IJCVR, Vol. 2, No. 4, 2011, pp. 302-31
Extraction of Projection Profile, Run-Histogram and Entropy Features Straight from Run-Length Compressed Text-Documents
Document Image Analysis, like any Digital Image Analysis requires
identification and extraction of proper features, which are generally extracted
from uncompressed images, though in reality images are made available in
compressed form for the reasons such as transmission and storage efficiency.
However, this implies that the compressed image should be decompressed, which
indents additional computing resources. This limitation induces the motivation
to research in extracting features directly from the compressed image. In this
research, we propose to extract essential features such as projection profile,
run-histogram and entropy for text document analysis directly from run-length
compressed text-documents. The experimentation illustrates that features are
extracted directly from the compressed image without going through the stage of
decompression, because of which the computing time is reduced. The feature
values so extracted are exactly identical to those extracted from uncompressed
images.Comment: Published by IEEE in Proceedings of ACPR-2013. arXiv admin note: text
overlap with arXiv:1403.778
An experimental and analytical investigation of isolated rotor flap-lag stability in forward flight
For flap-lag stability of isolated rotors, experimental and analytical investigations are conducted in hover and forward flight on the adequacy of a linear quasisteady aerodynamics theory with dynamic inflow. Forward flight effects on lag regressing mode are emphasized. A soft inplane hingeless rotor with three blades is tested at advance ratios as high as 0.55 and at shaft angles as high as 20 degrees. In combination with lag natural frequencies, collective pitch settings and flap-lag coupling parameters, the data base comprises nearly 1200 test points (damping and frequency) in forward flight and 200 test points in hover. By computerized symbolic manipulations, an analytic model is developed in substall to predict stability margins with mode identification. It also predicts substall and stall regions to help explain the correlation between theory and data
THE OLFACTORY SYSTEM REGULATES ACUTE MOUNTAIN SICKNESS
OBJECTIVE:Hyperventilation is the first response to hypoxia in high altitude (HA). Our study on rats was designed to establish an integrated hypothesis to include hyperventilation, increased activity of hypothalamicpituitary-adrenocortical axis (HPA) in response to initial exposure to hypoxia and failure of adaptation to stress in olfactory bulbectomised rats. .METHODS:Albino rats whose olfactory lobes were removed were subjected to hypoxia and hypothermic conditions. Blood and urine samples were collected at various stages to measure biochemical parameters. Rats whose olfactory systems were intact were used as controls.RESULTS:The results suggested that the olfactory system regulated pituitary function and that in rats whose olfactory lobes were removed failed to adapt to the stress created by hypoxia and hypothermia.CONCLUSIONS:Acute Mountain Sickness (AMS) is a type of stress. Normal rats when subjected to stress such as AMSare able to adapt. This adaptation is lost when the olfactory bulbs are removed. It is postulated that serotonin receptors in the hypothalamus, through the splanchnic pathway regulate stress. This mechanism is independent of ACTH – Cortisol feed back system. Perhaps irregular and rapid respiratory rhythm simulates physiological Olfactory Bulbectomy during rapid climbing and AMS manifests as a failure of stress adaptation
Streaming Video QoE Modeling and Prediction: A Long Short-Term Memory Approach
HTTP based adaptive video streaming has become a popular choice of streaming
due to the reliable transmission and the flexibility offered to adapt to
varying network conditions. However, due to rate adaptation in adaptive
streaming, the quality of the videos at the client keeps varying with time
depending on the end-to-end network conditions. Further, varying network
conditions can lead to the video client running out of playback content
resulting in rebuffering events. These factors affect the user satisfaction and
cause degradation of the user quality of experience (QoE). It is important to
quantify the perceptual QoE of the streaming video users and monitor the same
in a continuous manner so that the QoE degradation can be minimized. However,
the continuous evaluation of QoE is challenging as it is determined by complex
dynamic interactions among the QoE influencing factors. Towards this end, we
present LSTM-QoE, a recurrent neural network based QoE prediction model using a
Long Short-Term Memory (LSTM) network. The LSTM-QoE is a network of cascaded
LSTM blocks to capture the nonlinearities and the complex temporal dependencies
involved in the time varying QoE. Based on an evaluation over several publicly
available continuous QoE databases, we demonstrate that the LSTM-QoE has the
capability to model the QoE dynamics effectively. We compare the proposed model
with the state-of-the-art QoE prediction models and show that it provides
superior performance across these databases. Further, we discuss the state
space perspective for the LSTM-QoE and show the efficacy of the state space
modeling approaches for QoE prediction
- …
