Leader Mudit Mathur
Photogrammetry is the art, science, and technology of obtaining reliable information about physical objects and the environment through the processes of recording, measuring and interpreting photographic images/magazines/2008/sept and patterns of electromagnetic radiant energy and other phenomena. Alternatively, it is the science of optimising photography for and the extraction of measurements, in 2 or 3 dimensions, from photographs.
OPEN SOURCE INITIATIVE
Open source is a development method for software that draws on the power of distributed peer review and transparency of process. The forebode of open source is better quality, higher reliability, more flexibility, lower cost, and an end to predatory vendor lock-in. The Open Source Initiative Approved License trademark and programme creates a nexus of trust around which developers, users, corporations and governments that can organise open-source cooperation.
Precedence to the Open Source Initiative (OSI) includes the history of Unix, Internet free software and the hacker culture. A strand of events that lead to the formation of OSI began with the publication of Eric Raymond’s paper ‘The Cathedral and the Bazaar’ in 1997. As of today, open source is the biggest warehouse of applications which otherwise would not have been accessible due to proprietary.
THE OPEN SOURCE DEFINITION
Open source doesn’t just mean access to the source code. The distribution terms of open-source software ideally should comply with the following criteria:
The license shall not restrict any party from selling or giving away the software as a component of an aggregate software distribution containing programmes from several different sources. The license shall not require permission royalty or other fee for such sale.
The programme must include source code and must allow distribution in source code as well as compiled form. Where some form of a product is not distributed with source code, there must be a well-publicised means of obtaining the source code for no more than a reasonable reproduction cost preferably, downloading via the Internet without charge. The source code must be the preferred form in which a programmer would modify the programme. Deliberately obfuscated source code is not allowed. Intermediate forms such as the output of a preprocessor or translator are not allowed.
The license must allow modifications and derived works, and must allow them to be distributed under the same terms as the license of the original software.
Integrity of The Author’s Source Code
The license may restrict source-code from being distributed in modified form only if the license allows the distribution of “patch files” with the source code for the purpose of modifying the programme at build time. The license must explicitly permit distribution of software built from modified source code. The license may require derived works to carry a different name or version number from the original software.
No Discrimination Against Persons or Groups
The license must not discriminate against any person or group of persons.
No Discrimination against Fields of Endeavour
The license must not restrict anyone from making use of the programme in a specific field of endeavour. For example, it may not restrict the programme from being used in a business or from being used for genetic research.
Distribution of License
The rights attached to the programme must apply to everyone to whom the programme is redistributed without the need for execution of an additional license by those parties.
License Must Not Be Specific to a Product
The rights attached to the programme must not depend on the programme’s being part of a particular software distribution. If the programme is extracted from that distribution and used or distributed within the terms of the programme’s license, all parties to whom the programme is redistributed should have the same rights as those that are granted in conjunction with the original software distribution.
License Must Not Restrict Other Software
The license must not place restrictions on other software that is distributed along with the licensed software. For example, the license must not insist that all other programmes distributed on the same medium must/ must not be open-source software.
License Must Be Technology-Neutral
No provision of the license may be predicated on any individual technology or style of interface.
OPEN SOURCE PHOTOGRAMMETRY (OSP)
In open source photogrammetry, OSGeo is been accepted for Google Summer of Code 2007 programme. This programme provides funding for students to work on open source projects under the support of experienced intellectual. The projects participating through OSGeo are
• GDAL, • GeoServer,
• GeoTools, • GRASS,
• MapGuide, • PostGIS ,
• uDig, • OpenJUMP and
These applications are well suited for processing lots of very large geospatial raster images/magazines/2008/sept – satellite, aerial and multispectral imagery. Written in C++, it provides libraries, command line tools and a number of applications for scientific analysis and geospatial prototyping and production.
COMPARISON OF GIS SOFTWARE (LICENSE, SOURCE, & OPERATING SYSTEM SUPPORT )
In recent years, GIS industry has witnessed phenomenal growth in the development and adoption of open source technologies. The technical GIS community adopted open source technology relatively early, and now mainstream GIS and broader IT industries have come on board as open source products have matured. Organisations are realising the value of incorporating open source software as a core part of their business. The open source GIS has a tremendous advantage of customisation as per the user requirements and the expertise available. A few open source GIS are listed here. Details of many of them can be collected from the site (https://opensourcegis.org/).
OPEN SOURCE PHOTOGRAMMETRY APPLICATIONS
OSSIM is a high performance software system for remote sensing, image pro-
cessing, open source, cross platform software distribution, geographical information systems and photogrammetry. OSSIM-based processing tasks can be run on high performance computing arrays, such as Beowulf clusters, for massive performance increase.
OPEN-SOURCE VISUALISATION AND THE VIRTUAL TERRAIN PROJECT (VTP)
The goal of VTP is to further the creation of tools for easily constructing any part of the real world in interactive, 3D digital form. VTP is synergetic convergence of CAD, GIS, visual simulation, surveying and remote sensing. VTP gathers information and tracks progress in areas such as procedural scene construction, feature extraction and rendering algorithms. VTP writes and supports a set of software tools, including an interactive runtime environment (VTP Enviro). The tools and their source code are freely shared to help accelerate the adoption and development of the necessary technologies.
OpenEV is a GIS viewer application, originally designed for a Linux environment but recently ported to work under Windows as well. OpenEV’s most interesting design feature is the reliance on OpenGL as a screen rendering language. The reliance on OpenGL means OpenEV can provide very good render performance, but it also restricts the platforms on which OpenEV can be run. OpenEV can view large image files and create 3D views of the images/magazines/2008/sept.
ACCURATE, LIVING GLOBE
A number of impressive solutions including OssimPlanet, Google Earth, WorldWind and Microsoft Virtual Earth exist. OssimPlanet has a slightly different focus and set of priorities than these web-based visualisation and navigation systems. These include:
• Geodetic accuracy,
• Native file access,
• Sensor model support
• Live feeds and collaboration,
• Open source and open development.
Most spinning globes require that data be “pre-cooked” into internal formats and layers. Double precision accuracy, native file access and remote collaboration set most of them apart from other navigation and visualisation systems built on top of an advanced open source 3D visualisation system – Open- SceneGraph and the OSSIM libraries. It supports OGC WMS interfaces, conditional access to NASA WorldWind servers and direct drag and drop with most geospatial formats. The topography is generated from geoids and DTED or SRTM format elevation cells.
In fact if we see a truly photogrammetry system amongst the entire bunch, E-Foto stands apart. The idea behind the E-Foto project was to offer a simple set of software that could help students understand the principles of photogrammetry – reading the e-book, using the software, taking a look at its source code and even modifying it or developing new modules for it. The project is based on two main principles (pillars): freedom and self-teaching. The software development is in its early stage of development and hence needs a rare combination of photogrammetry specialist and software developer to modify it.
Like many developments in the IT sector, open source seemed to come out of nowhere. People who thought the whole thing as a storm in a teacup began to realise otherwise when Microsoft’s CEO Steve Ballmer called open source “a cancer” in 2001. It’s in human history that we rarely detected the tempest before it arrives; the open source is tempest in waiting.
“This work is a collection of works done in the field of open source and photogrammetry by various individuals and institutes. Author takes no claim in either designing the concept or its methodologies, however, direct integration of isolated works in the field of open source and photogrammetry is been done in this article. Suitable cross references are marked. “
American Society for Photogrammetry and Remote Sensing (ASPRS)
Michael Tiemann https://www.opensource.org/about