522 research outputs found
Impact of Feature Representation on Remote Sensing Image Retrieval
Remote sensing images are acquired using special platforms, sensors and are classified as aerial, multispectral and hyperspectral images. Multispectral and hyperspectral images are represented using large spectral vectors as compared to normal Red, Green, Blue (RGB) images. Hence, remote sensing image retrieval process from large archives is a challenging task. Remote sensing image retrieval mainly consist of feature representation as first step and finding out similar images to a query image as second step. Feature representation plays important part in the performance of remote sensing image retrieval process. Research work focuses on impact of feature representation of remote sensing images on the performance of remote sensing image retrieval. This study shows that more discriminative features of remote sensing images are needed to improve performance of remote sensing image retrieval process
Deep Image Retrieval: A Survey
In recent years a vast amount of visual content has been generated and shared
from various fields, such as social media platforms, medical images, and
robotics. This abundance of content creation and sharing has introduced new
challenges. In particular, searching databases for similar content, i.e.content
based image retrieval (CBIR), is a long-established research area, and more
efficient and accurate methods are needed for real time retrieval. Artificial
intelligence has made progress in CBIR and has significantly facilitated the
process of intelligent search. In this survey we organize and review recent
CBIR works that are developed based on deep learning algorithms and techniques,
including insights and techniques from recent papers. We identify and present
the commonly-used benchmarks and evaluation methods used in the field. We
collect common challenges and propose promising future directions. More
specifically, we focus on image retrieval with deep learning and organize the
state of the art methods according to the types of deep network structure, deep
features, feature enhancement methods, and network fine-tuning strategies. Our
survey considers a wide variety of recent methods, aiming to promote a global
view of the field of instance-based CBIR.Comment: 20 pages, 11 figure
Understand-Before-Talk (UBT): A Semantic Communication Approach to 6G Networks
In Shannon theory, semantic aspects of communication were identified but
considered irrelevant to the technical communication problems. Semantic
communication (SC) techniques have recently attracted renewed research
interests in (6G) wireless because they have the capability to support an
efficient interpretation of the significance and meaning intended by a sender
(or accomplishment of the goal) when dealing with multi-modal data such as
videos, images, audio, text messages, and so on, which would be the case for
various applications such as intelligent transportation systems where each
autonomous vehicle needs to deal with real-time videos and data from a number
of sensors including radars. A notable difficulty of existing SC frameworks
lies in handling the discrete constraints imposed on the pursued semantic
coding and its interaction with the independent knowledge base, which makes
reliable semantic extraction extremely challenging. Therefore, we develop a new
lightweight hashing-based semantic extraction approach to the SC framework,
where our learning objective is to generate one-time signatures (hash codes)
using supervised learning for low latency, secure and efficient management of
the SC dynamics. We first evaluate the proposed semantic extraction framework
over large image data sets, extend it with domain adaptive hashing and then
demonstrate the effectiveness of "semantics signature" in bulk transmission and
multi-modal data
Learning to Evaluate Performance of Multi-modal Semantic Localization
Semantic localization (SeLo) refers to the task of obtaining the most
relevant locations in large-scale remote sensing (RS) images using semantic
information such as text. As an emerging task based on cross-modal retrieval,
SeLo achieves semantic-level retrieval with only caption-level annotation,
which demonstrates its great potential in unifying downstream tasks. Although
SeLo has been carried out successively, but there is currently no work has
systematically explores and analyzes this urgent direction. In this paper, we
thoroughly study this field and provide a complete benchmark in terms of
metrics and testdata to advance the SeLo task. Firstly, based on the
characteristics of this task, we propose multiple discriminative evaluation
metrics to quantify the performance of the SeLo task. The devised significant
area proportion, attention shift distance, and discrete attention distance are
utilized to evaluate the generated SeLo map from pixel-level and region-level.
Next, to provide standard evaluation data for the SeLo task, we contribute a
diverse, multi-semantic, multi-objective Semantic Localization Testset
(AIR-SLT). AIR-SLT consists of 22 large-scale RS images and 59 test cases with
different semantics, which aims to provide a comprehensive evaluations for
retrieval models. Finally, we analyze the SeLo performance of RS cross-modal
retrieval models in detail, explore the impact of different variables on this
task, and provide a complete benchmark for the SeLo task. We have also
established a new paradigm for RS referring expression comprehension, and
demonstrated the great advantage of SeLo in semantics through combining it with
tasks such as detection and road extraction. The proposed evaluation metrics,
semantic localization testsets, and corresponding scripts have been open to
access at github.com/xiaoyuan1996/SemanticLocalizationMetrics .Comment: 19 pages, 11 figure
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