@InProceedings{Mesquita:2017:ViSeOb,
author = "Mesquita, Rafael Galv{\~a}o de",
affiliation = "{Universidade Federal de Pernambuco}",
title = "Visual Search for Object Instances Guided by Visual Attention
Algorithms",
booktitle = "Proceedings...",
year = "2017",
editor = "Torchelsen, Rafael Piccin and Nascimento, Erickson Rangel do and
Panozzo, Daniele and Liu, Zicheng and Farias, Myl{\`e}ne and
Viera, Thales and Sacht, Leonardo and Ferreira, Nivan and Comba,
Jo{\~a}o Luiz Dihl and Hirata, Nina and Schiavon Porto, Marcelo
and Vital, Creto and Pagot, Christian Azambuja and Petronetto,
Fabiano and Clua, Esteban and Cardeal, Fl{\'a}vio",
organization = "Conference on Graphics, Patterns and Images, 30. (SIBGRAPI)",
publisher = "Sociedade Brasileira de Computa{\c{c}}{\~a}o",
address = "Porto Alegre",
keywords = "Visual search. saliency detection. visual attention. object
recognition. local feature detectors/descriptors. matching.",
abstract = "Visual attention is the process by which the human brain
prioritizes and controls visual stimuli and it is, among other
characteristics of the visual system, responsible for the fast way
in which human beings interact with the environment, even
considering a large amount of information to be processed. Visual
attention can be driven by a bottom-up mechanism, in which low
level stimuli of the analysed scene, like color, guides the
focused region to salient regions (regions that are distinguished
from its neighborhood or from the whole scene); or by a top-down
mechanism, in which cognitive factors, like expectations or the
goal of concluding certain task, define the attended location.
This Thesis investigates the use of visual attention algorithms to
guide (and to accelerate) the search for objects in digital
images. Inspired by the bottom-up mechanism, a saliency detector
based on the estimative of the scenes background combined with the
result of a Laplacian-based operator, referred as BLS (Background
Laplacian Saliency), is proposed. Moreover, a modification in SURF
(Speeded-Up Robust Features) local feature detector/descriptor,
named as patch-based SURF, is designed so that the recognition
occurs iteratively in each focused location of the scene, instead
of performing the classical recognition (classic search), in which
the whole scene is analysed at once. The search mode in which the
patch-based SURF is applied and the order of the regions of the
image to be analysed is defined by a saliency detection algorithm
is called BGMS. The BLS and nine other state-of-the-art saliency
detection algorithms are experimented in the BGMS. Results
indicate, in average, a reduction to (i) 73% of the classic search
processing time just by applying patch-based SURF in a random
search, (ii) and to 53% of this time when the search is guided by
BLS. When using other state-of-the-art saliency detection
algorithms, between 55% and 133% of the processing time of the
classic search is needed to perform recognition. Moreover,
inspired by the top-down mechanism, it is proposed the BGCO, in
which the visual search occurs by prioritizing scene descriptors
according to its Hamming distance to the descriptors of a given
target object. The BGCO uses Bloom filters to represent feature
vectors that are similar to the descriptors of the searched object
and it has constant space and time complexity in relation to the
number of elements in the set of the descriptors of the target.
Experiments showed a reduction in the processing time to 80% of
the required time when the classic search is performed. Finally,
by using the BGMS and the BGCO in an integrated way, the
processing time of the search was reduced to 44% of the execution
time required by the classic search.",
conference-location = "Niter{\'o}i, RJ, Brazil",
conference-year = "17-20 Oct. 2017",
language = "en",
ibi = "8JMKD3MGPAW/3PJ97CE",
url = "http://urlib.net/ibi/8JMKD3MGPAW/3PJ97CE",
targetfile = "MesquitaMello_final.pdf",
urlaccessdate = "2024, Apr. 29"
}