Item


Exploring three faint source detections methods for aperture synthesis radio images

Wide-field radio interferometric images often contain a large population of faint compact sources. Due to their low intensity/noise ratio, these objects can be easily missed by automated detection methods, which have been classically based on thresholding techniques after local noise estimation. The aim of this paper is to present and analyse the performance of several alternative or complementary techniques to thresholding. We compare three different algorithms to increase the detection rate of faint objects. The first technique consists of combining wavelet decomposition with local thresholding. The second technique is based on the structural behaviour of the neighbourhood of each pixel. Finally, the third algorithm uses local features extracted from a bank of filters and a boosting classifier to perform the detections. The methods’ performances are evaluated using simulations and radio mosaics from the Giant Metrewave Radio Telescope and the Australia Telescope Compact Array. We show that the new methods perform better than well-known state of the art methods such as SExtractor, SAD and DUCHAMP at detecting faint sources of radio interferometric images

This work has been supported by Grant AYA2010-21782-C03-02 from Ministerio de Economia y Competitividad. M. Masias holds an FI grant 2012FI_B1 00122. We thank the staff of the GMRT that made these observations possible

© New Astronomy, 2015, vol. 36, p. 86-99

Elsevier

Author: Peracaula i Bosch, Marta
Torrent Palomeras, Albert
Masias Moyset, Marc
Lladó Bardera, Xavier
Freixenet i Bosch, Jordi
Martí Ribas, Josep
Sánchez-Sutil, J.R.
Muñoz-Arjonilla, A.J.
Paredes i Poy, Josep Maria
Date: 2015
Abstract: Wide-field radio interferometric images often contain a large population of faint compact sources. Due to their low intensity/noise ratio, these objects can be easily missed by automated detection methods, which have been classically based on thresholding techniques after local noise estimation. The aim of this paper is to present and analyse the performance of several alternative or complementary techniques to thresholding. We compare three different algorithms to increase the detection rate of faint objects. The first technique consists of combining wavelet decomposition with local thresholding. The second technique is based on the structural behaviour of the neighbourhood of each pixel. Finally, the third algorithm uses local features extracted from a bank of filters and a boosting classifier to perform the detections. The methods’ performances are evaluated using simulations and radio mosaics from the Giant Metrewave Radio Telescope and the Australia Telescope Compact Array. We show that the new methods perform better than well-known state of the art methods such as SExtractor, SAD and DUCHAMP at detecting faint sources of radio interferometric images
This work has been supported by Grant AYA2010-21782-C03-02 from Ministerio de Economia y Competitividad. M. Masias holds an FI grant 2012FI_B1 00122. We thank the staff of the GMRT that made these observations possible
Format: application/pdf
ISSN: 1384-1076
Document access: http://hdl.handle.net/10256/11701
Language: eng
Publisher: Elsevier
Collection: MICINN/PN 2011-2013/AYA2010-21782-C03-02
Reproducció digital del document publicat a: http://dx.doi.org/10.1016/j.newast.2014.10.006
Articles publicats (D-ATC)
Is part of: © New Astronomy, 2015, vol. 36, p. 86-99
Rights: Tots els drets reservats
Subject: Imatges -- Processament
Image processing
Imatge, Tècniques d’
Imaging systems
Title: Exploring three faint source detections methods for aperture synthesis radio images
Type: info:eu-repo/semantics/article
Repository: DUGiDocs

Subjects

Authors


Warning: Unknown: write failed: No space left on device (28) in Unknown on line 0

Warning: Unknown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct (/var/lib/php5) in Unknown on line 0