Imagery refers to raster based datasets acquired from sensors on satellites or aircraft.

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516 views

Tasseled Cap Transformation Rapid Eye

I want to do tasseled cap transformation on rapid eye data. the main question would be about the parameters which are used. Somebody has a suggestion? A short update concerning this attempt to ...
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1answer
297 views

Is it possible to determine Collection Date of ESRI World Imagery Basemap

It seems like it was possible to do this with Google Imagery if I recall but is there any way to determine the date of collection of Esri's World Imagery basemap (or other basemaps) at a given ...
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3answers
686 views

Which Software can derive building footprints from imagery?

I'm looking for a software solution that can process large areas of imagery to produce building footprints. For the area of interest, I can source either satellite stereo pairs or oblique imagery. I ...
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2answers
129 views

How many stereo satellite imagery required to prepare DEM of an area?

I want to know how to find the nos. of scene of stereo CARTISAT-1 data required to prepare DEM of an area(say 84000 sq km)? any suggestion/solution/calculation?
3
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2answers
401 views

Third party base layer other than Google map

Can we use third party base map (images tiles) for displaying vector data?, like we use google map as base layer for displaying vector data in OpenLayers application.
3
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1answer
548 views

gdal_merge.py with single band raster

I'm trying to mosaic the True Marble world imagery 250M geotiffs using gdal_merge.py though one of them doesn't have RGB bands like the rest and gdal_merge fails (same number of bands is listed as a ...
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4answers
228 views

Place image without using points in QGIS

I am trying to find a GIS software that does this, so I am trying QGIS but other suggestions are welcome. I have a basic shp boundary such as a rectangle. I want to be able to import an unreferenced ...
3
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2answers
170 views

Geographically georeference image with limited information

It is possible to semi-accurately georeference an image given only the following information? I'd like to do this programmatically. Center point of terrain, Lat/Lng (WGS84) Pitch of camera FOV ...
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2answers
135 views

Google maps white striations / false artifacts

What are the common white striations running from NW to SE visible when you zoom in around 5mi scale? For example at (+81, -80)? But they appear 'all over'. Are they snow drifts? or satellite sweeps? ...
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2answers
261 views

Memory and Processing Efficient Approach to Read a Timeseries in Python

I am trying to store a timeseries of high resolution raster images containing NDVI values into a dictionary for calculations. I am curious as to which approach may the most efficient when loading ...
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1answer
3k views

Is there a way to export online ESRI basemap layers to raster?

I have been working on polygonizing the vegetation areas in some counties from imagery. When I have the mosaic raster locally I can easily get the polygons using Image Classification Toolbar. But when ...
3
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1answer
1k views

Clipping MrSID files in ArcGIS Desktop?

Does anyone have experience subsetting/clipping a large NAIP imagery file in MrSID format? Some of the NAIP files we have are by county and they have really large file sizes. The files are from the ...
3
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1answer
64 views

Obtaining free satellite imagery for Australian floods?

How can I obtain free satellite imagery for Australia? I want to find the extend of flood in specific time. I have already tried land-sat.But unfortunately there is no data available for that specific ...
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2answers
133 views

Is it possible to highlight water steam sources on Landsat 7 image?

I am trying whether it is possible to view hot steam sources like power plant cooling towers and resulting cloud using satellite images. I was advised to try Landsat (needed free data for initial ...
3
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1answer
265 views

How to easily import aerial imagery into gvSIG?

I have used ArcView GIS 3.x for years. I have decided to try some of the free GIS desktop software. I am now trying gvSIG. One feature I was hoping for was the importation of aerial imagery relatively ...
3
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1answer
524 views

How can I georeference a second image without losing georeferencing for first image in ArcGIS 10?

What happens: 1) Take a map with an image that was georeferenced earlier, which works fine. 2) Add a second image to the TOC and fire up the georeferencing toolbar. 3) Select the new, ...
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1answer
500 views

WMS Image Services Do Not Display

We recently upgraded to Image Server 10.0.1 and in the process our WMS Image Services quit displaying. The connection to them works in ArcCatalog, but it never displays. If I preview the service it ...
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6answers
351 views

Source for high-res subscription imagery service

I'm developing a diagramming tool using aerial imagery as a reference layer. This tool should allow the user to zoom in quite close to a roadway or intersection. Unfortunately none of the public map ...
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1answer
322 views

gdal_warp of multiple rasters keeping maxium intensity value

I have multiple rasters which overlap eachother geospatially but do not completely occupy the same space. I can combine them with gdalwarp like: gdalwarp -s_srs EPSG:4326 *.tif larger_output.tif ...
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1answer
30 views

How to know the required scene required to cover an area?

I want to know how to find the nos. of scene of LISS 4 data required to cover an area(say 84000 sq km)? any suggestion/solution/calculation?
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1answer
461 views

Viewing panoramic imagery in ArcGIS

Is there an ArcGIS extension or utility that will view 360 degree panoramic images? I've found utilities that are part of larger software packages for managing mobile scanning data, but all I'm after ...
3
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1answer
1k views

How to add images containing attributes in QGIS?

I am new to QGIS. I know how to add vector and raster files into QGIS. I have some satellite images taken at different times of the same location. In addition, there are some annotation data ...
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0answers
69 views

how can i save a satellite raster image as a layer file in arcmap 10.2

I am trying to save a raster satellite image from esri world imagery as a georeferenced layer file. i still want to be able to zoom in and out as i can when veiwing it through the server.
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175 views

Counting animals using near infrared imagery from a drone [closed]

I am playing around with an idea of using a near infrared camera to fly transects to count animals on the ground. I have been involved in such work earlier, but on bigger mammals and observer based ...
3
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0answers
495 views

Novel ways of filling in missing values in a raster

I am looking for robust ways to fill in missing values in some rasters. They all have a single layer. Missing values consist of single pixels to medium sized patches. Rasters are around 1000 x 1000 ...
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0answers
107 views

Is there a tutorial explaining the basics of WMS?

I'm building some software that needs to download satellite map images to display behind some survey charts. I understand that, to download these images, I need access to a Web Map Service. The only ...
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2answers
159 views

What exactly is 'anti-aliased image generation'?

I tried to google it, but didn't quite get it. Any help and/or examples? Thank you!
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3answers
2k views

Where to download 4 band NAIP imagery?

I seem to recall USGS Earthexplorer providing current and historic 4 band NAIP imagery over the last few years. It appears that these data have been migrated to the National Map. However, the ...
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2answers
1k views

Where can I find non-rectified stereo satellite imagery?

I'm looking for free (as in beer and as in commercial-use-friendly freedom) sources of stereo satellite imagery. I assume that such imagery should not be rectified since that would remove the benefits ...
2
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1answer
440 views

How to create NDVI map From LiDAR intensity and RGB image

I am new with GIS and I've been looking for ways on how I could create a NDVI map from LiDAR intensity and RGB image. Is there any way I could do this? I have read that you could create an intensity ...
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2answers
451 views

How to identify image footprints of an aerial photograph

I need a tool that will take aerial images with Lat, Long, and Alt in their EXIF data and produce foot prints of the images. We need to verify that the images cover the photographed area with proper ...
2
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1answer
420 views

How to extract vegetation polygons from Imagery using Python?

I have been trying to roughly polygonize vegetation areas from Imagery (RGB). I tried using Iso Cluster Unsupervised Classification (Spatial Analyst) but it is still too detailed for my purpose. I ...
2
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2answers
417 views

Is there a source for leaf-off aerial imagery?

I am looking for leaf-off imagery for Oklahoma, Kansas and Texas. 1m leaf-off imagery would be ideal, although any substitute would be helpful. I need fairly high resolution imagery to distinguish ...
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3answers
374 views

Finding Satellite Imagery For Use Without Internet Connection

So, I am not a GIS expert. I just write software and I've done some work with ArcMap, ArcGIS Server, and FalconView. What I need is world wide satellite imagery I can use on a local machine. Street ...
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3answers
55 views

Saving extent of satellite imagery in ArcGIS Desktop?

I'm using 50cm imagery for the whole country of South Africa, which make zooming and panning painfully slow. Can I save imagery for just the area I am working with (ie. data frame, city, province)? ...
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1answer
291 views

Rf-Classification seems to work but gives an error 15 seconds later

This is my code. It classifies an imagery-stack(xvars) and reads a shapefile with training-points. If I run single rows they work. Even if I run them all, they work and start to predict but after 15s ...
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2answers
63 views

How to produce maps with copyright imagery on it in GRASS?

I'm having some trouble with a GIS that I've got to produce. I work for a contractor and we'll have to produce maps to do the work for our client. The client has specified that if we print maps out ...
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3answers
187 views

Medium resolution imagery for the US?

For my web map application http://ian01.geog.psu.edu/geoserver/www/pa/pa3.html I have three levels of background imagery as the user zooms in. At small scales I'm using NASA Blue Marble and a large ...
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1answer
32 views

Primary and secondary data

If I am creating data from satellite imagery, is this classed as primary or secondary data? If I am creating slope data from a DTM, is this then classed as primary or secondary data?
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1answer
36 views

Are there free maps available that can show me land planted with oil palm?

Currently I am taking gps coordinates of oil palm plantations in Africa. I'm putting the waypoints in a GIS program but the free basemap provided isn't always giving high resolution images, making it ...
2
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2answers
351 views

SPOT NDVI time series

I have 423 spot.vgt ndvi from first April 1998 till 31 Dec 2009. I want to know how to stack these NDVI to have one image for time series analysis? Or better to ask how is it possible to analyze a ...
2
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2answers
454 views

Convert Georeferenced imagery to vector data using python

Are there any opensource tools I could use to take a projected georeferenced image such as a jpg with world file, that is UTM projection such as NAD83 and convert it into distinct vector polygons ...
2
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1answer
228 views

Trouble viewing MrSID in ArcView 3.3

I have been using 3.3 for some time and now I have Arcmap10 on the same computer. My problem is that I cannot pull up the Mr Sid files. 3.3 can't find them ,the id has the right info but no image of ...
2
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1answer
74 views

Why does the peak of a mountain appear bright on Radar images

Why does the top of a mountain appear bright on a SAR (radar) image. I know that the peak of a mountain is subject to a layover effect, thus appearing closer on the radar image than the bottom part of ...
2
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1answer
52 views

QGIS: raster image georeference and overlay

I've created a grid and points in QGIS which I used to survey. Using a test image at the moment and I'm trying to fit this image as an overlay within a boundary. When I insert the image it has a white ...
2
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2answers
102 views

Stereoscopy Software

I'm learning the Manual Photogrammetry process, Stereoscopy, to Process UAV Imagery. I'd like to know about others software, especially open source or low cost. ERDAS Imagine, Erdas Extensions for ...
2
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1answer
77 views

Imagery on March 6, 2014 @ Lat 42dd55'22“ N, Long 079dd37'36” W

I am looking for any advice where to find imagery on March 6, 2014 (or a few days following) for: I have searched the USGS, ImageHunter, and Digital Globe with no luck. Does anyone have a resource ...
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5answers
289 views

Where can I get high-resolution (at least 1 foot) imagery of California?

Is there a national site or state site that will allow me to download High Res (1') aerial imagery of California? I have tried Cal-Atlas Download but they are at one meter. I have also tried USGS ...
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2answers
1k views

How to compress raster image for publishing?

I have a (8-bit) satellite image that is e 6 gb. Is there a way I can compress the image smaller size without losing the quality? Format: .tif Reason: After publish the image, I notice a higher usage ...
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1answer
287 views

How to programatically replace ArcGIS Online image with new imagery in mxd's?

I have many mxds that previously used ArcGIS Online Bing imagery. I want to replace those with newly purchased imagery. I know I need to use the arcpy.mapping.MapDocument module to do this though not ...