Montage Image Mosaic Software
Encyclopedia
Montage is a software toolkit used in astronomy
to assemble astronomical images in Flexible Image Transport System (FITS)
format into composite images, called mosaics, that preserve the calibration and positional fidelity of the original input images. It won a NASA Space Act Award in 2006. The software is described in detail by Jacob et al (2009).
Montage was developed to support scientific research. It enables astronomers to create images of regions of the sky that are too large to be be produced by astronomical cameras
. It also creates composite images of a region of the sky that has been measured with different wavelengths and with different instruments; the composite appears as if the area was measured with the same instrument on the same telescope.
Montage is also widely used in developing the infrastructure of the next generation of data-aware computing and cyber-infrastructure, including:
–compliant C for performance and portability. The toolkit contains software components that perform the steps needed to compute a mosaic. Montage operates as a workflow application
, where each component creates an output file that becomes the input to a subsequent component. Figure 2 shows how these components operate together to produce a mosaic. The toolkit design offers flexibility to users. They may, for example, use Montage as a re-projection tool, or deploy a custom background rectification algorithm while taking advantage of the re-projection and co-addition engines.
Montage runs on the command line under all common Unix and Linux platforms, and the same code runs on desktop, cluster and super-computer environments. It is highly parallelizable and has been run through all common workflow parallelization techniques. On a cluster of 128 2.3-GHz processors running Red Hat Linux, it can process 40 million pixels in 32 minutes.
. New versions are released periodically to correct defects and include enhanced functionality. The latest release is version 3.3 (December, 2010).
The distribution includes software components for creating mosaics, ancillary modules for managing and manipulating images, all third-party libraries, and modules for running Montage in parallel on clusters, supercomputers, clouds and grid through the Pegasus workflow management tool and the Message Passing Interface (MPI)
.
The service uses Virtual Observatory (VO)
protocols to access the images. There are plans to extend the service to include more data sets and to offer larger and multi-color mosaics.
A Python wrapper developed by Thomas Robitaille at the Harvard-Smithsonian Center for Astrophysics
automates some of the manual Montage functions and facilitates mosaicking and re-projecting.
A BASH script developed by Inseok Song at the University of Georgia
creates a mosaic of the Pleiades star cluster
from online Digitized Sky Survey (DSS)
data.
A set of C-shell scripts contributed by Dr. Colin Aspin create full-color mosaics of regions of the sky using images from 2MASS, DSS and SDSS.
, California Institute of Technology, the Jet Propulsion Laboratory and the Center for Advanced Computer Research, California Institute of Technology, in collaboration with the Information Sciences Institute
, University of Southern California
.
Montage is maintained at the Infrared Processing and Analysis Center, with support from the Information Sciences Institute at the University of Southern California and the Computational Institute at the University of Chicago
.
.
Astronomy
Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...
to assemble astronomical images in Flexible Image Transport System (FITS)
FITS
Flexible Image Transport System is a digital file format used to store, transmit, and manipulate scientific and other images. FITS is the most commonly used digital file format in astronomy...
format into composite images, called mosaics, that preserve the calibration and positional fidelity of the original input images. It won a NASA Space Act Award in 2006. The software is described in detail by Jacob et al (2009).
Montage was developed to support scientific research. It enables astronomers to create images of regions of the sky that are too large to be be produced by astronomical cameras
Charge-coupled device
A charge-coupled device is a device for the movement of electrical charge, usually from within the device to an area where the charge can be manipulated, for example conversion into a digital value. This is achieved by "shifting" the signals between stages within the device one at a time...
. It also creates composite images of a region of the sky that has been measured with different wavelengths and with different instruments; the composite appears as if the area was measured with the same instrument on the same telescope.
Features
Montage performs the following steps to compute a mosaic according to the user’s specifications, as follows:- Discover the geometry of the input images on the sky from the attributes recorded in the input FITS and use it to calculate the geometry of the output mosaic on the sky. These input images and the output mosaic are two-dimensional representations of regions of the three-dimensional curved surface of the sky. By analogy with terrestrial cartography, a mathematical projectionMap projectionA map projection is any method of representing the surface of a sphere or other three-dimensional body on a plane. Map projections are necessary for creating maps. All map projections distort the surface in some fashion...
describes the relationship between the pixel coordinates in the image and the pixels on three-dimensional surface of the sky. As in cartography, there are many projections in use in astronomy, which formally described them in the World Coordinate System (WCS. Montage supports all projections in the WCS. - Re-project the input images to the required spatial scale, coordinate system, image projection, and image rotation of the output mosaic.
- Model the background radiationBackground radiationBackground radiation is the ionizing radiation constantly present in the natural environment of the Earth, which is emitted by natural and artificial sources.-Overview:Both Natural and human-made background radiation varies by location....
in the input images to achieve common fluxFluxIn the various subfields of physics, there exist two common usages of the term flux, both with rigorous mathematical frameworks.* In the study of transport phenomena , flux is defined as flow per unit area, where flow is the movement of some quantity per time...
scales and background levels across the mosaics. - Co-add the re-projected, background-corrected images into a mosaic.
Applications
Montage is used primarily in scientific research and in the creation of scientific products. Recent examples include:- Stock and Barlow (2010) used it to search for ejecta from WR-stars by creating mosaics of images from the AAO/UKST Southern Hα Survey (SHS).
- Aguirre et al. (2010) used Montage to re-project images to create an atlas of images for the Bolocam Galactic Plane Survey (BGPS)Bolocam Galactic Plane Survey (BGPS)Observations for the Bolocam Galactic Plane Survey took place from June 2005 until September 2007 and covers 170 square degrees of the galactic plane visible from the northern hemisphere. The survey detected 8400 sources to a limiting non-uniform 1-sigma noise level in the range 30 to 60 mJy/beam...
, a millimeter-wave continuum survey of the Galactic plane.
- Anderson et al. (2010) used it to re-sample 350 μm maps of data from the Herschel Space TelescopeHerschel Space ObservatoryThe Herschel Space Observatory is a European Space Agency space observatory sensitive to the far infrared and submillimetre wavebands. It is the largest space telescope ever launched, carrying a single mirror of in diameter....
in their study of the physical properties of the dust of the HII region RCW 120.
- The Arecibo Legacy Fast ALFA survey (ALFALFA) (Giovanelli et al. 2005) used Montage to create a large wide-field mosaic of neutral hydrogen emission at 21 cm.
Montage is also widely used in developing the infrastructure of the next generation of data-aware computing and cyber-infrastructure, including:
- Designing fault-tolerant task scheduling in distributed environments
- Exploring issues of data provenance in scientific workflows
- Exploring the cost and performance of scientific applications running on cloudsCloud computingCloud computing is the delivery of computing as a service rather than a product, whereby shared resources, software, and information are provided to computers and other devices as a utility over a network ....
- Developing application performance frameworks
Design and Performance
Montage was developed as a toolkit written in American National Standards (ANSI)Ansi
Ansi is a village in Kaarma Parish, Saare County, on the island of Saaremaa, Estonia....
–compliant C for performance and portability. The toolkit contains software components that perform the steps needed to compute a mosaic. Montage operates as a workflow application
Bioinformatics workflow management systems
A bioinformatics workflow management system is a specialized form of workflow management system designed specifically to compose and execute a series of computational or data manipulation steps, or a workflow, in a specific domain of science, bioinformatics....
, where each component creates an output file that becomes the input to a subsequent component. Figure 2 shows how these components operate together to produce a mosaic. The toolkit design offers flexibility to users. They may, for example, use Montage as a re-projection tool, or deploy a custom background rectification algorithm while taking advantage of the re-projection and co-addition engines.
Montage runs on the command line under all common Unix and Linux platforms, and the same code runs on desktop, cluster and super-computer environments. It is highly parallelizable and has been run through all common workflow parallelization techniques. On a cluster of 128 2.3-GHz processors running Red Hat Linux, it can process 40 million pixels in 32 minutes.
Licensing and Distribution
Montage is freely available for download and use through a non-exclusive, non-commercial license agreement issued by the California Institute of Technology and the Jet Propulsion Laboratory from the Montage Web site. The software code, documentation and sample files are considered open source softwareOpen-source software
Open-source software is computer software that is available in source code form: the source code and certain other rights normally reserved for copyright holders are provided under a software license that permits users to study, change, improve and at times also to distribute the software.Open...
. New versions are released periodically to correct defects and include enhanced functionality. The latest release is version 3.3 (December, 2010).
The distribution includes software components for creating mosaics, ancillary modules for managing and manipulating images, all third-party libraries, and modules for running Montage in parallel on clusters, supercomputers, clouds and grid through the Pegasus workflow management tool and the Message Passing Interface (MPI)
Message Passing Interface
Message Passing Interface is a standardized and portable message-passing system designed by a group of researchers from academia and industry to function on a wide variety of parallel computers...
.
System Requirements
Montage is built with a simple make script on all common Unix and Linux platforms. It requires 300 MB of disk space for installation. The amount of memory and disk space needed for processing depends on the size of the input and output images, which is calculated using a formula described on the software's Disk Space System Requirements page. Montage does not operate on Microsoft Windows platforms, but has been run on Linux emulators running under Windows.Web Service
In addition to the software toolkit, an online Image Mosaic Service uses Montage to generate image mosaics requested on a simple web form. It offers images from three important wide-area data sets:- The Two-Micron All Sky Survey (2MASS)2MASSObservations for the Two Micron All-Sky Survey began in 1997 and were completed in 2001 at two telescopes located one each in the northern and southern hemispheres to ensure coverage of the entire sky...
, a survey of the entire sky in three Near-Infrared bands. - The Sloan Digital Sky Survey (SDSS)Sloan Digital Sky SurveyThe Sloan Digital Sky Survey or SDSS is a major multi-filter imaging and spectroscopic redshift survey using a dedicated 2.5-m wide-angle optical telescope at Apache Point Observatory in New Mexico, United States. The project was named after the Alfred P...
, which maps one-quarter of the sky in the blue, visible and red. - The Digitized Sky Surveys (DSS)Digitized Sky SurveyThe Digitized Sky Survey is a digital version of several photographic atlases of the night sky, and an ongoing project to produce more digital versions of photographic astronomical datasets.- Versions and source material :...
from the Space Telescope Science Institute (STScI), which cover the whole sky in the blue, visible, and red.
The service uses Virtual Observatory (VO)
Virtual Observatory
Virtual observatory is a collection of interoperating data archives and software tools which utilize the internet to form a scientific research environment in which astronomical research programs can be conducted....
protocols to access the images. There are plans to extend the service to include more data sets and to offer larger and multi-color mosaics.
Support
Montage maintains a dedicated help desk, which can be contacted through a Web form .Community Contributions to Montage
Members of the Montage user community have contributed scripts that enhance or extend Montage’s functionality, including:A Python wrapper developed by Thomas Robitaille at the Harvard-Smithsonian Center for Astrophysics
Harvard-Smithsonian Center for Astrophysics
The Harvard–Smithsonian Center for Astrophysics is one of the largest and most diverse astrophysical institutions in the world, where scientists carry out a broad program of research in astronomy, astrophysics, earth and space sciences, and science education...
automates some of the manual Montage functions and facilitates mosaicking and re-projecting.
A BASH script developed by Inseok Song at the University of Georgia
University of Georgia
The University of Georgia is a public research university located in Athens, Georgia, United States. Founded in 1785, it is the oldest and largest of the state's institutions of higher learning and is one of multiple schools to claim the title of the oldest public university in the United States...
creates a mosaic of the Pleiades star cluster
Pleiades (star cluster)
In astronomy, the Pleiades, or Seven Sisters , is an open star cluster containing middle-aged hot B-type stars located in the constellation of Taurus. It is among the nearest star clusters to Earth and is the cluster most obvious to the naked eye in the night sky...
from online Digitized Sky Survey (DSS)
Digitized Sky Survey
The Digitized Sky Survey is a digital version of several photographic atlases of the night sky, and an ongoing project to produce more digital versions of photographic astronomical datasets.- Versions and source material :...
data.
A set of C-shell scripts contributed by Dr. Colin Aspin create full-color mosaics of regions of the sky using images from 2MASS, DSS and SDSS.
Credits
Montage was developed at the Infrared Processing and Analysis Center (IPAC)Infrared Processing and Analysis Center
The Infrared Processing and Analysis Center is the NASA science center responsible for the data processing, analysis, and archiving of NASA's infrared astronomy and astrophysics missions...
, California Institute of Technology, the Jet Propulsion Laboratory and the Center for Advanced Computer Research, California Institute of Technology, in collaboration with the Information Sciences Institute
Information Sciences Institute
The Information Sciences Institute is a research and development unit of the University of Southern California's Viterbi School of Engineering which focuses on computer and communications technology and information processing...
, University of Southern California
University of Southern California
The University of Southern California is a private, not-for-profit, nonsectarian, research university located in Los Angeles, California, United States. USC was founded in 1880, making it California's oldest private research university...
.
Montage is maintained at the Infrared Processing and Analysis Center, with support from the Information Sciences Institute at the University of Southern California and the Computational Institute at the University of Chicago
University of Chicago
The University of Chicago is a private research university in Chicago, Illinois, USA. It was founded by the American Baptist Education Society with a donation from oil magnate and philanthropist John D. Rockefeller and incorporated in 1890...
.
Acknowledgment
Montage was funded by the National Aeronautics and Space Administration's Earth Science Technology Office, Computational Technologies Project, under Cooperative Agreement Number NCC5-626 between NASA and the California Institute of Technology. The Web-based Image Mosaic Service uses software developed by IPAC for the U.S. National Virtual Observatory, which is sponsored by the National Science FoundationNational Science Foundation
The National Science Foundation is a United States government agency that supports fundamental research and education in all the non-medical fields of science and engineering. Its medical counterpart is the National Institutes of Health...
.
External links
- Montage Web site
- Montage Web Service
- U.S. Virtual Astronomical Observatory
- Better Ways to Make Large Mosaics? Astrobetter blog post and discussion about Montage pros and cons
- Pegasus Workflow Management System Web site
- Montage A Rising Star in Grid-Enabled Sky Mosaics Feature article in International Science Grid This Week
- Pegasus invites new communities to saddle up Feature article in International Science Grid This Week
- Cloud Computing in the Age of Data-Intensive Science Feature article on SPIE Web site
- NASA Space Act Award page
- Infrared Processing and Analysis CenterInfrared Processing and Analysis CenterThe Infrared Processing and Analysis Center is the NASA science center responsible for the data processing, analysis, and archiving of NASA's infrared astronomy and astrophysics missions...