5,101 research outputs found
Exploiting feature representations through similarity learning, post-ranking and ranking aggregation for person re-identification
Person re-identification has received special attention by the human analysis
community in the last few years. To address the challenges in this field, many
researchers have proposed different strategies, which basically exploit either
cross-view invariant features or cross-view robust metrics. In this work, we
propose to exploit a post-ranking approach and combine different feature
representations through ranking aggregation. Spatial information, which
potentially benefits the person matching, is represented using a 2D body model,
from which color and texture information are extracted and combined. We also
consider background/foreground information, automatically extracted via Deep
Decompositional Network, and the usage of Convolutional Neural Network (CNN)
features. To describe the matching between images we use the polynomial feature
map, also taking into account local and global information. The Discriminant
Context Information Analysis based post-ranking approach is used to improve
initial ranking lists. Finally, the Stuart ranking aggregation method is
employed to combine complementary ranking lists obtained from different feature
representations. Experimental results demonstrated that we improve the
state-of-the-art on VIPeR and PRID450s datasets, achieving 67.21% and 75.64% on
top-1 rank recognition rate, respectively, as well as obtaining competitive
results on CUHK01 dataset.Comment: Preprint submitted to Image and Vision Computin
A Pose-Sensitive Embedding for Person Re-Identification with Expanded Cross Neighborhood Re-Ranking
Person re identification is a challenging retrieval task that requires
matching a person's acquired image across non overlapping camera views. In this
paper we propose an effective approach that incorporates both the fine and
coarse pose information of the person to learn a discriminative embedding. In
contrast to the recent direction of explicitly modeling body parts or
correcting for misalignment based on these, we show that a rather
straightforward inclusion of acquired camera view and/or the detected joint
locations into a convolutional neural network helps to learn a very effective
representation. To increase retrieval performance, re-ranking techniques based
on computed distances have recently gained much attention. We propose a new
unsupervised and automatic re-ranking framework that achieves state-of-the-art
re-ranking performance. We show that in contrast to the current
state-of-the-art re-ranking methods our approach does not require to compute
new rank lists for each image pair (e.g., based on reciprocal neighbors) and
performs well by using simple direct rank list based comparison or even by just
using the already computed euclidean distances between the images. We show that
both our learned representation and our re-ranking method achieve
state-of-the-art performance on a number of challenging surveillance image and
video datasets.
The code is available online at:
https://github.com/pse-ecn/pose-sensitive-embeddingComment: CVPR 2018: v2 (fixes, added new results on PRW dataset
Component-based Attention for Large-scale Trademark Retrieval
The demand for large-scale trademark retrieval (TR) systems has significantly
increased to combat the rise in international trademark infringement.
Unfortunately, the ranking accuracy of current approaches using either
hand-crafted or pre-trained deep convolution neural network (DCNN) features is
inadequate for large-scale deployments. We show in this paper that the ranking
accuracy of TR systems can be significantly improved by incorporating hard and
soft attention mechanisms, which direct attention to critical information such
as figurative elements and reduce attention given to distracting and
uninformative elements such as text and background. Our proposed approach
achieves state-of-the-art results on a challenging large-scale trademark
dataset.Comment: Fix typos related to authors' informatio
Unsupervised Graph-based Rank Aggregation for Improved Retrieval
This paper presents a robust and comprehensive graph-based rank aggregation
approach, used to combine results of isolated ranker models in retrieval tasks.
The method follows an unsupervised scheme, which is independent of how the
isolated ranks are formulated. Our approach is able to combine arbitrary
models, defined in terms of different ranking criteria, such as those based on
textual, image or hybrid content representations.
We reformulate the ad-hoc retrieval problem as a document retrieval based on
fusion graphs, which we propose as a new unified representation model capable
of merging multiple ranks and expressing inter-relationships of retrieval
results automatically. By doing so, we claim that the retrieval system can
benefit from learning the manifold structure of datasets, thus leading to more
effective results. Another contribution is that our graph-based aggregation
formulation, unlike existing approaches, allows for encapsulating contextual
information encoded from multiple ranks, which can be directly used for
ranking, without further computations and post-processing steps over the
graphs. Based on the graphs, a novel similarity retrieval score is formulated
using an efficient computation of minimum common subgraphs. Finally, another
benefit over existing approaches is the absence of hyperparameters.
A comprehensive experimental evaluation was conducted considering diverse
well-known public datasets, composed of textual, image, and multimodal
documents. Performed experiments demonstrate that our method reaches top
performance, yielding better effectiveness scores than state-of-the-art
baseline methods and promoting large gains over the rankers being fused, thus
demonstrating the successful capability of the proposal in representing queries
based on a unified graph-based model of rank fusions
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