Some of the problems facing by GIS service provider company for GIS service are competitive price, increased staff salaries, unavailability of skilled personnel, incapability to keep existing personnel, Increasing client’s demands, and dull earnings etc. All the above reasons make the companies to think about outsourcing.
Various points come into our mind while choosing a GIS outsourcing services partner .
The Key points may include
• Go through the services provided by those companies whom you are going to outsource your work.
• Analyze your needs and choose the company which can provide all your requirements.
• Go through their website deeply and understand their services thoroughly.
• Check the feedback and testimonials provided by the satisfied customers.
• Whenever you choose a company you have to check all your requirements. Otherwise you have to split up your needs to various companies which may not help to achieve cost benefits.
• The main idea behind the outsourcing is to reduce overheads and achieve cost benefits.
Some of the Outsourcing benefits are as follows
• Access to World Class Capabilities
• Cash Infusion
• Function Difficult to Manage or Out of Control
• Improve Company Focus
• Reduce Operating Costs
• Reduce Risk
• Resources not Available Internally
The GIS services may include
• Image Georectification/ georeferencing
• Geocoding
• Customization and Application Development
• Data Integration and data Format Conversion
• GIS spatial analysis services
and Modeling
• Map Digitization / Vectorization
• Enterprise GIS
• Feature Extraction
• Web mapping etc
Then finally we can choose those companies providing quality output, 24/7 customer service, capability to understand the client requirements, deadlines, technologies & needs may be considered for outsourcing.
Monday, November 9, 2009
Monday, November 2, 2009
What is Photogrammetry services?
We all knows that Photogrammetry is a remote sensing technology developed in which geometric properties about objects are determined from photographic images.
Photogrammetry is used in different fields, such as topographic mapping, architecture, engineering, manufacturing, quality control, weather forecasting, police investigation, and geology. Also it is very helpful to archaeologists to produce plans of large or complex sites and by meteorologists as a way to determine the actual wind speed of a tornado where objective weather data cannot be obtained. It is also used to combine live action with computer generated imagery in movie post-production.
Digital photogrammetry in GIS services includes Aerial triangulation,Aerial photogrammetry service, DTM DEM generation, orthophoto production and rectification, color balancing, Ortho mosaicing and tile generation, pan sharpening, contour generation, digital elevation model (DEM) extraction, 3D terain visualization, orthophotography services,geo-rectification services, photogrammetry service,Orthophoto rectification service,orthophoto generation,remote sensing services and LiDAR data processing services.
Photogrammetry is used in different fields, such as topographic mapping, architecture, engineering, manufacturing, quality control, weather forecasting, police investigation, and geology. Also it is very helpful to archaeologists to produce plans of large or complex sites and by meteorologists as a way to determine the actual wind speed of a tornado where objective weather data cannot be obtained. It is also used to combine live action with computer generated imagery in movie post-production.
Digital photogrammetry in GIS services includes Aerial triangulation,Aerial photogrammetry service, DTM DEM generation, orthophoto production and rectification, color balancing, Ortho mosaicing and tile generation, pan sharpening, contour generation, digital elevation model (DEM) extraction, 3D terain visualization, orthophotography services,geo-rectification services, photogrammetry service,Orthophoto rectification service,orthophoto generation,remote sensing services and LiDAR data processing services.
Thursday, August 27, 2009
Mobile Mapping services
Mobile social mapping service that allows people to share their location with friends.
For instance, let's say you are in France. Instead of having your approximate location detected and shared automatically, you can manually set your location for elsewhere - perhaps a visit to Niagara Falls.
Mobile mapping refers to a means of collecting geospatial data using mapping sensors mounted on a mobile platform. Its development was primarily driven by the advances in digital imaging and direct-georeferencing technologies.
The ability to map a location has become an integral part of the online and mobile experience.
In the online and mobile world, mapping services from Microsoft and Google have in fact trained Yellow Pages users and advertisers on how to immediately benefit from mapping services on websites and mobile portals. Mapping services give our company the opportunity to connect buyers and sellers even more easily than before.
As the Google Maps code is almost entirely Javascript and XML, some end-users reverse-engineered the tool and produced client-side scripts and server-side hooks which allowed a user or website to introduce expanded or customized features into the Google Maps interface.
Using the core engine and the map/satellite images hosted by Google, such tools can introduce custom location icons, location coordinates and metadata , and even custom map image sources into the Google Maps interface. The script-insertion tool Greasemonkey provides a large number of client-side scripts to customize Google Maps data.
The growing market penetration of Internet mapping, satellite imaging and personal navigation has opened up great research and business opportunities to geospatial communities. Multi-platform and multi-sensor integrated mapping technology has clearly established a trend towards fast geospatial data acquisition.
Sensors can be mounted on various platforms, such as satellites, aircrafts or helicopters, terrestrial vehicles, water-based vessels, and may even be hand-carried by individuals.
With the escalating use of telecommunication networks and the increasing availability of low-cost and portable sensors, mobile mapping has become more dynamic, and even pervasive. The book addresses a wide variety of research issues in the mobile mapping community, ranging from system development to sensor integration, imaging algorithms and mobile GIS applications. This book will provide researchers and practitioners a good overall view of what is being developed in this topical area.
For instance, let's say you are in France. Instead of having your approximate location detected and shared automatically, you can manually set your location for elsewhere - perhaps a visit to Niagara Falls.
Mobile mapping refers to a means of collecting geospatial data using mapping sensors mounted on a mobile platform. Its development was primarily driven by the advances in digital imaging and direct-georeferencing technologies.
The ability to map a location has become an integral part of the online and mobile experience.
In the online and mobile world, mapping services from Microsoft and Google have in fact trained Yellow Pages users and advertisers on how to immediately benefit from mapping services on websites and mobile portals. Mapping services give our company the opportunity to connect buyers and sellers even more easily than before.
As the Google Maps code is almost entirely Javascript and XML, some end-users reverse-engineered the tool and produced client-side scripts and server-side hooks which allowed a user or website to introduce expanded or customized features into the Google Maps interface.
Using the core engine and the map/satellite images hosted by Google, such tools can introduce custom location icons, location coordinates and metadata , and even custom map image sources into the Google Maps interface. The script-insertion tool Greasemonkey provides a large number of client-side scripts to customize Google Maps data.
The growing market penetration of Internet mapping, satellite imaging and personal navigation has opened up great research and business opportunities to geospatial communities. Multi-platform and multi-sensor integrated mapping technology has clearly established a trend towards fast geospatial data acquisition.
Sensors can be mounted on various platforms, such as satellites, aircrafts or helicopters, terrestrial vehicles, water-based vessels, and may even be hand-carried by individuals.
With the escalating use of telecommunication networks and the increasing availability of low-cost and portable sensors, mobile mapping has become more dynamic, and even pervasive. The book addresses a wide variety of research issues in the mobile mapping community, ranging from system development to sensor integration, imaging algorithms and mobile GIS applications. This book will provide researchers and practitioners a good overall view of what is being developed in this topical area.
Tuesday, June 30, 2009
Tuesday, March 3, 2009
What is advantages of modern GIS?
GIS has become somewhat mandatory. Our day-to-day myriad activities of life cannot go on without the helping hands of GIS.
Developed recently for the purpose of using and studying geographic information, geography underpins GIS and is the key to understanding it. It expresses and describes the locations of objects and features relating to the distribution and patterns of physical and human features that exist on the Earth’s surface.
Modern GIS
Before the advancement of modern GIS, analysis procedures would have been manually undertaken using transparent overlays or run through very slow and incompetent machines with far less power than today’s machines. GIS in the past mainly meant the information obtained from maps.
The indispensable advantage of modern GIS is that all the functionality for working with manifold sets of geographic data are assembled and automated within one piece of software with improved efficiency and speed.
The input, storage and display of geographical information are now realized in a computer and hence the features and themes can be manipulated, combined and analyzed to generate new information.
Different GIS software packages are available with different functionality and interfaces. ESRI is the world’s most popular GIS software package.
Common examples of GIS
Geographic information is as wide and varied from socio-economic or demographic data to physical and environmental data, treated as separate l ‘themes’ of similar types of information. Eg: Physical features or phenomena such as rivers, roads, forests, earthquakes, volcanoes, erosion, floods, vegetation etc. and Human features or phenomena such as population, migration, electoral territories, poverty, religion, health etc.
One such theme could relate to all the ‘rivers’ in a country. The physical features can include flooding and pollution. The location element is the postcode.
One of the main sources of ‘human’ geographic information is the Census. It records a large number of variables about every person in the a country including employment, housing and health. The geography element of it is the location of where people live.
Essentially, geographic information states WHAT is WHERE which needs to record these two elements somehow. Data can be captured from aerial photography, satellite images, field samples, land surveying, population censuses, global positioning systems (GPS) and government administrative records among others.
For combining geographic information themes, geography or location is used as the common denominator or the link. It has the potential to generate new information on patterns and relationships between multiple sets of geographic information that would otherwise be missed, and to aid in answering more complex questions or decision-making.
A typical example is Jon Snow’s investigation of Cholera in Victorian London in 1854. He identified the locations of incidences of Cholera against the location of water pumps, and noticed its gathering pattern around the Broad Street water pump. He identified the contaminated source and created the beginning of modern epidemiology. A map of just the water pumps or incidences of Cholera alone would have been of little value.
Again take the example of flood risk maps where the combined geographic information on the locations of properties and the locations of flood zones can help to identify properties at risk of flooding. This combined information is of huge value to environmental groups and insurance companies providing new information that would not be detectable otherwise.
Modern GIS has several advantages over the old techniques of map-making and information gathering. Some of modern GIS are:
1.Can cover large study areas (the whole world if necessary)
2.Deal with larger amounts of data
3.Can easily select any sub-study area
4.Can cope with frequent and infinite edits and changes
5.More powerful and resistant to damage
6.Quicker and more efficient
7.Less person, time and money
The Census is the most familiar examples of how GIS can store and display a number of large datasets for the entire country quickly and easily. Without the help of GIS, you would have had to search manually through records on your computer on telephone staff at the Census office to get information about your area of interest.
With GIS, data for any area can be accessed quickly and easily according to a location. We can now store and show maps and aerial photographs covering the whole of a country. For example, Multimap through which you can know exactly where every town and village in the UK was, you would be unable to provide the level of information that Multimap is able to do in just a few seconds. Essentially, you are able to customise your data to suit your needs.
GIS software has a large variety of tools of varying levels of complexity. Shown below are some core standard functions common to GIS software packages.
Query: Ask questions of feature attributes like: where is _? What’s the nearest_? What intersects with _?
Mapping and cartography: Visualize features and edit symbology and colours to create an output map with title, scale bar, north arrow etc.
Select: Classify features and their attributes that meet some criteria.
Distance: Estimate the distance between features.
Buffers: Rings drawn around features at a particular distance from the features.
Overlay: The display of diverse layers of information at one location.
Clip: Makes an input layer to the size and extent of a selected layer.
Merge: Merges multiple layers into a single layer.
Raster analysis: A complete separate suite of tools for raster analysis which includes classifying cells, deriving aspect and slope, mosaicing and calculating new cell values among many others.
3D: Data can be analyzed with ‘height’ in 3-dimensions for powerful visualization
Who uses GIS and Why?
GIS has evolved into a technology that is used by a huge number of industries and agencies to help plan, design, engineer, build and maintain information infrastructures that effects our everyday lives.
Use of GIS in different industry
Forestry: Inventory and management of resources
Police: Crime mapping to target resources
Epidemiology: To link clusters of disease to sources
Transport: Monitoring routes
Utilities: Managing pipe networks
Oil: Monitoring ships and managing pipelines
Central and local government: Evidence for funding and policy (eg.) deprivation
Health: Planning services and health impact assessments
Environment agencies: Identifying areas of risk from e.g. flood
Emergency departments e.g. ambulance: Planning quickest routes
Retail: Store location
Marketing: Locating target customers
Military: Troop movement
Mobile phone companies: Locating masts
Land ReGIStry: Recording and managing land and property
Estate agents: Locating properties that match certain criteria
Insurance: Identifying risk e.g. properties at risk of flooding
Agriculture: Analyzing crop yields
Regards
SBL GEOMATICS
Developed recently for the purpose of using and studying geographic information, geography underpins GIS and is the key to understanding it. It expresses and describes the locations of objects and features relating to the distribution and patterns of physical and human features that exist on the Earth’s surface.
Modern GIS
Before the advancement of modern GIS, analysis procedures would have been manually undertaken using transparent overlays or run through very slow and incompetent machines with far less power than today’s machines. GIS in the past mainly meant the information obtained from maps.
The indispensable advantage of modern GIS is that all the functionality for working with manifold sets of geographic data are assembled and automated within one piece of software with improved efficiency and speed.
The input, storage and display of geographical information are now realized in a computer and hence the features and themes can be manipulated, combined and analyzed to generate new information.
Different GIS software packages are available with different functionality and interfaces. ESRI is the world’s most popular GIS software package.
Common examples of GIS
Geographic information is as wide and varied from socio-economic or demographic data to physical and environmental data, treated as separate l ‘themes’ of similar types of information. Eg: Physical features or phenomena such as rivers, roads, forests, earthquakes, volcanoes, erosion, floods, vegetation etc. and Human features or phenomena such as population, migration, electoral territories, poverty, religion, health etc.
One such theme could relate to all the ‘rivers’ in a country. The physical features can include flooding and pollution. The location element is the postcode.
One of the main sources of ‘human’ geographic information is the Census. It records a large number of variables about every person in the a country including employment, housing and health. The geography element of it is the location of where people live.
Essentially, geographic information states WHAT is WHERE which needs to record these two elements somehow. Data can be captured from aerial photography, satellite images, field samples, land surveying, population censuses, global positioning systems (GPS) and government administrative records among others.
For combining geographic information themes, geography or location is used as the common denominator or the link. It has the potential to generate new information on patterns and relationships between multiple sets of geographic information that would otherwise be missed, and to aid in answering more complex questions or decision-making.
A typical example is Jon Snow’s investigation of Cholera in Victorian London in 1854. He identified the locations of incidences of Cholera against the location of water pumps, and noticed its gathering pattern around the Broad Street water pump. He identified the contaminated source and created the beginning of modern epidemiology. A map of just the water pumps or incidences of Cholera alone would have been of little value.
Again take the example of flood risk maps where the combined geographic information on the locations of properties and the locations of flood zones can help to identify properties at risk of flooding. This combined information is of huge value to environmental groups and insurance companies providing new information that would not be detectable otherwise.
Modern GIS has several advantages over the old techniques of map-making and information gathering. Some of modern GIS are:
1.Can cover large study areas (the whole world if necessary)
2.Deal with larger amounts of data
3.Can easily select any sub-study area
4.Can cope with frequent and infinite edits and changes
5.More powerful and resistant to damage
6.Quicker and more efficient
7.Less person, time and money
The Census is the most familiar examples of how GIS can store and display a number of large datasets for the entire country quickly and easily. Without the help of GIS, you would have had to search manually through records on your computer on telephone staff at the Census office to get information about your area of interest.
With GIS, data for any area can be accessed quickly and easily according to a location. We can now store and show maps and aerial photographs covering the whole of a country. For example, Multimap through which you can know exactly where every town and village in the UK was, you would be unable to provide the level of information that Multimap is able to do in just a few seconds. Essentially, you are able to customise your data to suit your needs.
GIS software has a large variety of tools of varying levels of complexity. Shown below are some core standard functions common to GIS software packages.
Query: Ask questions of feature attributes like: where is _? What’s the nearest_? What intersects with _?
Mapping and cartography: Visualize features and edit symbology and colours to create an output map with title, scale bar, north arrow etc.
Select: Classify features and their attributes that meet some criteria.
Distance: Estimate the distance between features.
Buffers: Rings drawn around features at a particular distance from the features.
Overlay: The display of diverse layers of information at one location.
Clip: Makes an input layer to the size and extent of a selected layer.
Merge: Merges multiple layers into a single layer.
Raster analysis: A complete separate suite of tools for raster analysis which includes classifying cells, deriving aspect and slope, mosaicing and calculating new cell values among many others.
3D: Data can be analyzed with ‘height’ in 3-dimensions for powerful visualization
Who uses GIS and Why?
GIS has evolved into a technology that is used by a huge number of industries and agencies to help plan, design, engineer, build and maintain information infrastructures that effects our everyday lives.
Use of GIS in different industry
Forestry: Inventory and management of resources
Police: Crime mapping to target resources
Epidemiology: To link clusters of disease to sources
Transport: Monitoring routes
Utilities: Managing pipe networks
Oil: Monitoring ships and managing pipelines
Central and local government: Evidence for funding and policy (eg.) deprivation
Health: Planning services and health impact assessments
Environment agencies: Identifying areas of risk from e.g. flood
Emergency departments e.g. ambulance: Planning quickest routes
Retail: Store location
Marketing: Locating target customers
Military: Troop movement
Mobile phone companies: Locating masts
Land ReGIStry: Recording and managing land and property
Estate agents: Locating properties that match certain criteria
Insurance: Identifying risk e.g. properties at risk of flooding
Agriculture: Analyzing crop yields
Regards
SBL GEOMATICS
GIS Mapping services
With the companies emerging in oil and gas, everyone is looking for an edge over the competition. Having access to professional and highly accurate pipeline maps will match the difference between failure and success. A complete pipeline map will provide all information your company needs to rise in competition. Furthermore, SBL has developed GIS pipeline energy datasets that are completely dependable. To be a leader you have to be accurate and precise in measurements and it would not be possible i absence of a accurate pipeline map provider.
Mapping services can be further classified as mobile mapping which is a cutting edge technology applied by another feature-packed GPS. GPS receivers locate your exact position on land or sea and provide visual appearance through navigation and mapping software . We can also produce digital maps, a tracklog summarizes starting time, Ending time, time travelled, Number of waypoints crossed, Distance covered and the average speed. GPS mapping software products provide powerful and easy to use tools to extend the features of almost any hand-held GPS.
GPS technology provides tracking of live objects like lost pets by monitoring & tracking softwares and devices. This works with a device attached to the pet's collar, which emits a signal that can be picked up with a special mobile-phone-type of handheld monitor. Similarly mobile phones being lost can also be tracked.
Have you ever wished for an easier and more enjoyable way to find a hidden treasure site lost hundreds of years ago ?
An easier way to locate a structure that disappeared in the last century? Have you ever stumbled on a remote spot and wished you had a sure way to remember its location?
If yes, then GPS can help you here.
Other mapping services includes web mapping automation & Geodatabase Designing Modelling. By understanding geography and people's relationship to location, we can make informed decisions about the way we live on our planet. Successful businesses use Business Geointelligence.
Regards
SBL GEOMATICS
By : N D
Mapping services can be further classified as mobile mapping which is a cutting edge technology applied by another feature-packed GPS. GPS receivers locate your exact position on land or sea and provide visual appearance through navigation and mapping software . We can also produce digital maps, a tracklog summarizes starting time, Ending time, time travelled, Number of waypoints crossed, Distance covered and the average speed. GPS mapping software products provide powerful and easy to use tools to extend the features of almost any hand-held GPS.
GPS technology provides tracking of live objects like lost pets by monitoring & tracking softwares and devices. This works with a device attached to the pet's collar, which emits a signal that can be picked up with a special mobile-phone-type of handheld monitor. Similarly mobile phones being lost can also be tracked.
Have you ever wished for an easier and more enjoyable way to find a hidden treasure site lost hundreds of years ago ?
An easier way to locate a structure that disappeared in the last century? Have you ever stumbled on a remote spot and wished you had a sure way to remember its location?
If yes, then GPS can help you here.
Other mapping services includes web mapping automation & Geodatabase Designing Modelling. By understanding geography and people's relationship to location, we can make informed decisions about the way we live on our planet. Successful businesses use Business Geointelligence.
Regards
SBL GEOMATICS
By : N D
Monday, February 2, 2009
CAD services and Georeferencing
The word ‘georeferencing’ was originally used to describe the process of referencing a map image to a geographic location.
To describe it now, georeferencing is a process of taking an image and assigning geographic coordinates to it or to georeference something means to define its existence in the physical space by establishing a relation between raster or vector images to map projections or coordinate systems. When data from different sources need to be compiled and used in any GIS application, it is important to have a common referencing system. This is brought about by using various georeferencing techniques.
The process of georeferencing
Georeferencing usually refers to the method by which locations in raster and vector GIS files are related to real earth-surface positions.
Raster data is often taken by scanning maps or collecting aerial photographs and satellite images. Scanned map datasets usually do not have any spatial reference information. The location information delivered with aerial photography and satellite imagery might be inadequate and the data need not align correctly with some other data you possess.
In order to use some raster datasets in conjunction with other spatial data, you sometimes need to align or georeference them to a map coordinate system which can be defines using a map projection to display the curved surface of the earth on a flat surface.
Georeference a raster dataset means defining its location using map coordinates and assigning a coordinate system. This process allows it to be viewed, queried, and analyzed in comparison with other geographic data.
How can you georeference a raster dataset?
Add the raster dataset to be aligned to your projected data in ArcMap.
Add control points that connect known raster dataset positions to the map coordinate positions.
When the alignment becomes correct, save the georeferencing information (registration) for further use.
Though Geomatics users are familiar with the term ‘georeferening’, many of the CAD users are not much aware of the term and the use of georeferencing in CAD.
Why is it needed?
A raster image has no particular size as it is made up of pixels. The size of the vectorised CAD/GIS drawing is determined by the raster's pixel dimensions, without georeferencing. The image resolution (DPI) can determine this. This image size usually has no relationship with the size of the drawing that the raster represents.
A CAD file is usually drawn in a local coordinate system and depicts spatial information which can be drawn accurately without being fixed to a higher global coordinate system. However, when the drawing needs to be related to a higher level in a mapping context with data from many different sources, tools in ArcMap can easily reposition a CAD file and integrate it into that higher level without altering the CAD file.
First thing is to find out two points on the CAD file that matches with two points in the map for which we can use the Georeferencing toolbar in ArcMap.
Different tools on the toolbar can support different workflows and below listed is an easy way to describe georeferencing a CAD file.
First step is to load the CAD drawing and ensure that one of the CAD feature layers are listed in the drop down menu of the georeferencing toolbar.
Zooming to the place roughly on the map where the CAD drawing is to be related is the next step. You can use the ‘fit to display’ tool on the menu to fix the CAD file in the map frame.
ArcMap snapping helps accurate placement of the CAD file which makes precise selection of control points based on existing geometry. Use the ‘rotate’ tool if the CAD file needs to be rotated to get the drawing nearer to its final position. This enables easy picking of control points.
You can use the interactive scaling tool also for the above mentioned reason.
Now when you select the ‘update georeferencing’ option, this creates a .WLD file that will be read from now on to put your CAD file in the right place.
Finally, the coordinates are always adjusted into this position. Now you can select a coordinate system for your CAD drawing so that you can assign or project its coordinates with reference to the map or during any other geospatial operation.
Regards
SBL GEOMATICS
Article By : RARIMA N S
To describe it now, georeferencing is a process of taking an image and assigning geographic coordinates to it or to georeference something means to define its existence in the physical space by establishing a relation between raster or vector images to map projections or coordinate systems. When data from different sources need to be compiled and used in any GIS application, it is important to have a common referencing system. This is brought about by using various georeferencing techniques.
The process of georeferencing
Georeferencing usually refers to the method by which locations in raster and vector GIS files are related to real earth-surface positions.
Raster data is often taken by scanning maps or collecting aerial photographs and satellite images. Scanned map datasets usually do not have any spatial reference information. The location information delivered with aerial photography and satellite imagery might be inadequate and the data need not align correctly with some other data you possess.
In order to use some raster datasets in conjunction with other spatial data, you sometimes need to align or georeference them to a map coordinate system which can be defines using a map projection to display the curved surface of the earth on a flat surface.
Georeference a raster dataset means defining its location using map coordinates and assigning a coordinate system. This process allows it to be viewed, queried, and analyzed in comparison with other geographic data.
How can you georeference a raster dataset?
Add the raster dataset to be aligned to your projected data in ArcMap.
Add control points that connect known raster dataset positions to the map coordinate positions.
When the alignment becomes correct, save the georeferencing information (registration) for further use.
Though Geomatics users are familiar with the term ‘georeferening’, many of the CAD users are not much aware of the term and the use of georeferencing in CAD.
Why is it needed?
A raster image has no particular size as it is made up of pixels. The size of the vectorised CAD/GIS drawing is determined by the raster's pixel dimensions, without georeferencing. The image resolution (DPI) can determine this. This image size usually has no relationship with the size of the drawing that the raster represents.
A CAD file is usually drawn in a local coordinate system and depicts spatial information which can be drawn accurately without being fixed to a higher global coordinate system. However, when the drawing needs to be related to a higher level in a mapping context with data from many different sources, tools in ArcMap can easily reposition a CAD file and integrate it into that higher level without altering the CAD file.
First thing is to find out two points on the CAD file that matches with two points in the map for which we can use the Georeferencing toolbar in ArcMap.
Different tools on the toolbar can support different workflows and below listed is an easy way to describe georeferencing a CAD file.
First step is to load the CAD drawing and ensure that one of the CAD feature layers are listed in the drop down menu of the georeferencing toolbar.
Zooming to the place roughly on the map where the CAD drawing is to be related is the next step. You can use the ‘fit to display’ tool on the menu to fix the CAD file in the map frame.
ArcMap snapping helps accurate placement of the CAD file which makes precise selection of control points based on existing geometry. Use the ‘rotate’ tool if the CAD file needs to be rotated to get the drawing nearer to its final position. This enables easy picking of control points.
You can use the interactive scaling tool also for the above mentioned reason.
Now when you select the ‘update georeferencing’ option, this creates a .WLD file that will be read from now on to put your CAD file in the right place.
Finally, the coordinates are always adjusted into this position. Now you can select a coordinate system for your CAD drawing so that you can assign or project its coordinates with reference to the map or during any other geospatial operation.
Regards
SBL GEOMATICS
Article By : RARIMA N S
Thursday, January 29, 2009
Ortho/Orthorectification process
In the areas of GIS data acquisition, visualization and general mapping,
digital satellite imagery and aerial photographs have a significant place.
Photographs obviously provide a solid visual effect. Imperceptible spatial concepts are more clearly understood by viewing the photographs. These are not photographs taken by ordinary cameras. These are very professional high-end cameras with higher zoom and clarity.
Another important role of these photos is to provide a foundation for collecting the spatial information needed. Data in the form of the satellite images or aerial photographs must be taken without any distortions, if you need to gather information useful for a mapping or GIS system in the case of roads, marine forms or vegetation.
This process of correcting the distortions of a satellite image of aerial photograph is called Orthophoto rectification .This process allows you to make direct and precise measurements of areas, distances, angles, positions etc.
Why an aerial photograph needs correction?
The main challenge of an aerial photograph compared to a non-aerial photograph is that an aerial photograph needs perspective correction. An aerial photo is usually captured at an angle to the object being photographed. Here, the perspective of the photograph will be incorrect with near objects compared to distant objects. By perspective correction, the objects in the image and the real world will have equal size.
Process of Orthophoto rectification service
As topographical variations in earth’s surface and the tilt of the satellite or the aerial sensors can affect the display of the features on the satellite or aerial image with regard to their distance. The image distortion will be more as the topographical diversity of the landscape is more.
Image data acquired by airborne and satellite image sensors are affected by systematic sensor and platform-induced geometry errors, which introduce terrain distortions when the image sensor is not pointing directly at the Nadir location of the sensor.
There can be hundreds of meters of terrain displacement. Image data over an area with at least a kilometer of vertical relief, with the sensor having an elevation angle of 60° (30° from Nadir), the image output will have nearly 600 meters of terrain displacement.
Errors in setting the reference elevation can cause further terrain displacement. Other than this, low elevation angles of images, imperfect terrain models, and inconsistency of sensor azimuth and elevation angles within an image alters the accuracy potential if image orthorectification is attempted. To overcome this defect, high elevation angles of the sensor is used with new high resolution satellite image of irregular terrain.
Creation of digital elevation model (DEM)
For the accurate removal of the image distortions, a digital elevation model (DEM) is used to make image orthorectification or Ortho mosaicing. The requisite DEM can be produced by semi-automatic DEM extraction software from stereo satellite scenes obtained by the QuickBird, IKONOS, SPOT-5, or ASTER satellite sensors, and stereo aerial photography.
In situations where higher mapping accuracy standards are required, the DEM is extracted from the already existing topographic maps with reference to a standard scale or collected using stereo satellite image data.
To obtain this accuracy standard, adequate GPS-derived ground control points (GCPs) are necessary. Other remote sensing techniques can also be used such as radar interferometry or LIDAR.
When a particular vector data needs to be extracted from satellite or aerial image data by raster-to-vector translation, the process of orthorectification of the remotely sensed image data can rectify all digital images of geological, environmental, topographic or any other source map which will be used in the GIS Mapping service environment.
For more informations visit SBL Geomatics
digital satellite imagery and aerial photographs have a significant place.
Photographs obviously provide a solid visual effect. Imperceptible spatial concepts are more clearly understood by viewing the photographs. These are not photographs taken by ordinary cameras. These are very professional high-end cameras with higher zoom and clarity.
Another important role of these photos is to provide a foundation for collecting the spatial information needed. Data in the form of the satellite images or aerial photographs must be taken without any distortions, if you need to gather information useful for a mapping or GIS system in the case of roads, marine forms or vegetation.
This process of correcting the distortions of a satellite image of aerial photograph is called Orthophoto rectification .This process allows you to make direct and precise measurements of areas, distances, angles, positions etc.
Why an aerial photograph needs correction?
The main challenge of an aerial photograph compared to a non-aerial photograph is that an aerial photograph needs perspective correction. An aerial photo is usually captured at an angle to the object being photographed. Here, the perspective of the photograph will be incorrect with near objects compared to distant objects. By perspective correction, the objects in the image and the real world will have equal size.
Process of Orthophoto rectification service
As topographical variations in earth’s surface and the tilt of the satellite or the aerial sensors can affect the display of the features on the satellite or aerial image with regard to their distance. The image distortion will be more as the topographical diversity of the landscape is more.
Image data acquired by airborne and satellite image sensors are affected by systematic sensor and platform-induced geometry errors, which introduce terrain distortions when the image sensor is not pointing directly at the Nadir location of the sensor.
There can be hundreds of meters of terrain displacement. Image data over an area with at least a kilometer of vertical relief, with the sensor having an elevation angle of 60° (30° from Nadir), the image output will have nearly 600 meters of terrain displacement.
Errors in setting the reference elevation can cause further terrain displacement. Other than this, low elevation angles of images, imperfect terrain models, and inconsistency of sensor azimuth and elevation angles within an image alters the accuracy potential if image orthorectification is attempted. To overcome this defect, high elevation angles of the sensor is used with new high resolution satellite image of irregular terrain.
Creation of digital elevation model (DEM)
For the accurate removal of the image distortions, a digital elevation model (DEM) is used to make image orthorectification or Ortho mosaicing. The requisite DEM can be produced by semi-automatic DEM extraction software from stereo satellite scenes obtained by the QuickBird, IKONOS, SPOT-5, or ASTER satellite sensors, and stereo aerial photography.
In situations where higher mapping accuracy standards are required, the DEM is extracted from the already existing topographic maps with reference to a standard scale or collected using stereo satellite image data.
To obtain this accuracy standard, adequate GPS-derived ground control points (GCPs) are necessary. Other remote sensing techniques can also be used such as radar interferometry or LIDAR.
When a particular vector data needs to be extracted from satellite or aerial image data by raster-to-vector translation, the process of orthorectification of the remotely sensed image data can rectify all digital images of geological, environmental, topographic or any other source map which will be used in the GIS Mapping service environment.
For more informations visit SBL Geomatics
Ornithology and GIS
During spring, flocks of migratory wading birds arrive from their natural habitat, which would be usually intolerably cool during winter, to a critical non-breeding habitat on the tropical places.
Protection of these migratory birds is a concern that needs real attention. Some of these birds from northern hemisphere fly more than 20,000 km a year in search of a suitable dwelling place for survival during the winter season.
The use of GIS and remote sensing technology can be used as an integral part to trace the migrating location of these birds from field mapping to reporting of the location.
One tip to find the birds of migration is to identify their food habit. This would give an idea of their prospective migrating location with regard to the availability of the specific food.
For instance, if we take the birds that usually migrate from Siberia to the tropical North coast of Australia. These migratory birds feed on small animals that live in mud such as crabs, snails and worms. These birds naturally migrate to the area of low muddy lands of Australia to feed and refill their energy for their journey back to their natural habitat.
Using compatible and innovative GPS units and enough field staff, samples can be collected from various points of the expected area of migration by producing progress maps and occasional species maps. By these procedures, even the presence of any new species in the area also can be identified.
To cite another example, some migratory birds have time and again halted in Malaysia during their roosting season that usually lasts from November to March because of its Matang Mangrove Forest.
The arrival of these migratory birds was observed by The Department of Wildlife and National Parks and they have decided to create a GIS database in order to study the biodiversity and sustainability of migratory birds.
Finally, they made a GIS database for the migratory birds and conducted an overall analysis on the captured data. The methodology run from need assessment to data collection, database development and system integration. This finally resulted in an analysis on the trends of bird migration, the properties of ecosystem, environment sensitivity analysis and spatial statistic analysis on the distribution of the migratory birds.
As already mentioned, the resultant migratory bird’s database contain statistical results on the trend of bird migration which in turn helped to identify the endangered species of migratory birds. When the endangered species are classified, measures and procedures for the maintenance of the mangrove areas are taken.
The database of the migratory birds with reference to the diversity and sustainability of the birds can been developed using ArcView 3.2, MapObject 2.0, Microsoft Visual Basic 6.0, AutoCadMap 2.0 and S-Plus 2000.
Regards
Geospatial services
Article By: RARIMA N S
Protection of these migratory birds is a concern that needs real attention. Some of these birds from northern hemisphere fly more than 20,000 km a year in search of a suitable dwelling place for survival during the winter season.
The use of GIS and remote sensing technology can be used as an integral part to trace the migrating location of these birds from field mapping to reporting of the location.
One tip to find the birds of migration is to identify their food habit. This would give an idea of their prospective migrating location with regard to the availability of the specific food.
For instance, if we take the birds that usually migrate from Siberia to the tropical North coast of Australia. These migratory birds feed on small animals that live in mud such as crabs, snails and worms. These birds naturally migrate to the area of low muddy lands of Australia to feed and refill their energy for their journey back to their natural habitat.
Using compatible and innovative GPS units and enough field staff, samples can be collected from various points of the expected area of migration by producing progress maps and occasional species maps. By these procedures, even the presence of any new species in the area also can be identified.
To cite another example, some migratory birds have time and again halted in Malaysia during their roosting season that usually lasts from November to March because of its Matang Mangrove Forest.
The arrival of these migratory birds was observed by The Department of Wildlife and National Parks and they have decided to create a GIS database in order to study the biodiversity and sustainability of migratory birds.
Finally, they made a GIS database for the migratory birds and conducted an overall analysis on the captured data. The methodology run from need assessment to data collection, database development and system integration. This finally resulted in an analysis on the trends of bird migration, the properties of ecosystem, environment sensitivity analysis and spatial statistic analysis on the distribution of the migratory birds.
As already mentioned, the resultant migratory bird’s database contain statistical results on the trend of bird migration which in turn helped to identify the endangered species of migratory birds. When the endangered species are classified, measures and procedures for the maintenance of the mangrove areas are taken.
The database of the migratory birds with reference to the diversity and sustainability of the birds can been developed using ArcView 3.2, MapObject 2.0, Microsoft Visual Basic 6.0, AutoCadMap 2.0 and S-Plus 2000.
Regards
Geospatial services
Article By: RARIMA N S
Thursday, January 1, 2009
Scarcity of photogrammetry companies vs more photogrammetry projects
Though the significance of GIS services are moving uphill, the scarcity of companies offering the services becomes a big issue now. When the growing demand cannot be met by us, the opportunities will be grabbed by the competitors.
Due to the spread of mapping sites like google maps, live maps etc., people have become more aware of the satellite images and the possibilities of digital mapping. Hence the popularity graph of GIS has taken a steady ascend now compared to the year 2005.
GIS makes use of specialized software that is in vogue for its variety of services and customized software for some of the projects according to the specifications of the client.
The GIS application areas are wide ranging from Forestry, Utilities, Oil and Gas industry, Central and local government, Public Health, Hospitality and Tourism, Environmental Management, Emergency Management, Retail Marketing and Management, Mobile mapping, Real Estate, Insurance, LIDAR and Laser Scanning , Agriculture and Research, Transportation ,to Public works.
What makes the scarcity in the photogrammetry companies? One reason is the difficulty to find people with specialization in photogrammerty. Many of the Western universities offer courses in this field. Things are not that easy in many of the Asian countries.
For a GIS company to be successful, it needs to have the appropriate infrastructure which updated technological advances. Moreover it requires highly experienced professionals to carry out the projects in photogrammetry. Other than this, very innovative and specialized workstations are quintessential for the undisturbed workflow of photogrammetry jobs.
Even if a company garners all the above mentioned essentials in this field, they have to pay through the nose to maintain them. This becomes another obstacle in the forming and functioning of a photogrammetry company.
There are very few GIS companies in India as compared to its wide ranging applications.
Regards
SBL GEOMATICS
Due to the spread of mapping sites like google maps, live maps etc., people have become more aware of the satellite images and the possibilities of digital mapping. Hence the popularity graph of GIS has taken a steady ascend now compared to the year 2005.
GIS makes use of specialized software that is in vogue for its variety of services and customized software for some of the projects according to the specifications of the client.
The GIS application areas are wide ranging from Forestry, Utilities, Oil and Gas industry, Central and local government, Public Health, Hospitality and Tourism, Environmental Management, Emergency Management, Retail Marketing and Management, Mobile mapping, Real Estate, Insurance, LIDAR and Laser Scanning , Agriculture and Research, Transportation ,to Public works.
What makes the scarcity in the photogrammetry companies? One reason is the difficulty to find people with specialization in photogrammerty. Many of the Western universities offer courses in this field. Things are not that easy in many of the Asian countries.
For a GIS company to be successful, it needs to have the appropriate infrastructure which updated technological advances. Moreover it requires highly experienced professionals to carry out the projects in photogrammetry. Other than this, very innovative and specialized workstations are quintessential for the undisturbed workflow of photogrammetry jobs.
Even if a company garners all the above mentioned essentials in this field, they have to pay through the nose to maintain them. This becomes another obstacle in the forming and functioning of a photogrammetry company.
There are very few GIS companies in India as compared to its wide ranging applications.
Regards
SBL GEOMATICS
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