24 research outputs found
Compact Hash Codes for Efficient Visual Descriptors Retrieval in Large Scale Databases
In this paper we present an efficient method for visual descriptors retrieval
based on compact hash codes computed using a multiple k-means assignment. The
method has been applied to the problem of approximate nearest neighbor (ANN)
search of local and global visual content descriptors, and it has been tested
on different datasets: three large scale public datasets of up to one billion
descriptors (BIGANN) and, supported by recent progress in convolutional neural
networks (CNNs), also on the CIFAR-10 and MNIST datasets. Experimental results
show that, despite its simplicity, the proposed method obtains a very high
performance that makes it superior to more complex state-of-the-art methods
Bloom Filters and Compact Hash Codes for Efficient and Distributed Image Retrieval
This paper presents a novel method for efficient image retrieval, based on a
simple and effective hashing of CNN features and the use of an indexing
structure based on Bloom filters. These filters are used as gatekeepers for the
database of image features, allowing to avoid to perform a query if the query
features are not stored in the database and speeding up the query process,
without affecting retrieval performance. Thanks to the limited memory
requirements the system is suitable for mobile applications and distributed
databases, associating each filter to a distributed portion of the database.
Experimental validation has been performed on three standard image retrieval
datasets, outperforming state-of-the-art hashing methods in terms of precision,
while the proposed indexing method obtains a speedup
Image Retrieval using Multi-scale CNN Features Pooling
In this paper, we address the problem of image retrieval by learning images
representation based on the activations of a Convolutional Neural Network. We
present an end-to-end trainable network architecture that exploits a novel
multi-scale local pooling based on NetVLAD and a triplet mining procedure based
on samples difficulty to obtain an effective image representation. Extensive
experiments show that our approach is able to reach state-of-the-art results on
three standard datasets.Comment: Accepted at ICMR 202
Characteristics and patterns of care of endometrial cancer before and during COVID-19 pandemic
Objective: Coronavirus disease 2019 (COVID-19) outbreak has correlated with the disruption of screening activities and diagnostic assessments. Endometrial cancer (EC) is one of the most common gynecological malignancies and it is often detected at an early stage, because it frequently produces symptoms. Here, we aim to investigate the impact of COVID-19 outbreak on patterns of presentation and treatment of EC patients. Methods: This is a retrospective study involving 54 centers in Italy. We evaluated patterns of presentation and treatment of EC patients before (period 1: March 1, 2019 to February 29, 2020) and during (period 2: April 1, 2020 to March 31, 2021) the COVID-19 outbreak. Results: Medical records of 5,164 EC patients have been retrieved: 2,718 and 2,446 women treated in period 1 and period 2, respectively. Surgery was the mainstay of treatment in both periods (p=0.356). Nodal assessment was omitted in 689 (27.3%) and 484 (21.2%) patients treated in period 1 and 2, respectively (p<0.001). While, the prevalence of patients undergoing sentinel node mapping (with or without backup lymphadenectomy) has increased during the COVID-19 pandemic (46.7% in period 1 vs. 52.8% in period 2; p<0.001). Overall, 1,280 (50.4%) and 1,021 (44.7%) patients had no adjuvant therapy in period 1 and 2, respectively (p<0.001). Adjuvant therapy use has increased during COVID-19 pandemic (p<0.001). Conclusion: Our data suggest that the COVID-19 pandemic had a significant impact on the characteristics and patterns of care of EC patients. These findings highlight the need to implement healthcare services during the pandemic