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

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348 views

viewing GMapCatcher downloaded tiles in ArcGIS Explorer? (as basemap?)

We have a full set of 20 zoom levels of downloaded satellite imagery that we downloaded with (and view in) GMapCatcher - great program! All of these operations are done offline (for a Search and ...
12
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3answers
834 views

Is there a programmatic way to retrieve Landsat 8 Satellite Images?

I have not been able to find out this myself, but is there a way to programmatic access Landsat 8 Satellite Images? I know that I can go to USGS EarthExplorer to search and browse through the scenes, ...
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2answers
260 views

What does MODIS data reflectance values (MOD13Q1) mean?

Several publications suggest filtering MODIS data (in my case MOD13Q1) prior to use. They recommended to filter out pixels having blue reflectance more than 10%, but what 10% here means? is it 10% of ...
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2answers
285 views

Practical Building Extraction Algorithm Implementation

I've been reading many papers over 3D building extraction using LiDAR data and Aerial images. I see that there are many different algorithms for doing such things, such as this and this. Those ...
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40 views

Satellite Imagery for North America with options for different CRS

Ok, everyone I think this question has been asked before and maybe there is no answer yet. I need a satellite imagery layer of North America where I can change the projection. The OpenLayers plugin ...
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0answers
95 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 ...
4
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1answer
111 views

Do OrthoRectified Images have shadow?

Orthorectified images have removed relief displacements and tilt displacements. Since the assumption of orthorectification is to keep the light source at infinite distance so that the light rays are ...
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1answer
739 views

How to convert a bil image into grid in ArcGIS?

GIS beginner here. I've downloaded RFE data from FEWSNET. It's a compressed file which includes .bil files. Now i want to convert this ".bil image" into a grid to use the precipitation data in an ...
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1answer
520 views

how to stack landsat 8 layers correctly?

i downloaded a landsat8 satellite image from USGS, it was separated into 12 layers. So, what i would like to do is to stack some of them. To do that, i am not sure which layer should be excluded from ...
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5answers
183 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 ...
2
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1answer
61 views

From where I can get 4-band satellite imagery of Sweden?

I'm looking for good quality, fine resolution 4-band satellite photos of Sweden for academic use (and I'm willing to pay for it). What I'm after is as detailed as possible photos of certain part of ...
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1answer
343 views

How to list raster bands?

I am interested in looping through a directory and listing only the red bands (Band 1) from 4-band NAIP imagery. From there I would like to mosaic all of the band 1 layers into a new single band ...
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1answer
83 views

Satellite imagery options for small/medium sized countries?

I need to create land cover classifications for a couple countries in central/eastern Asia. The largest country is 50,000km^2 and the smallest is 10,000km^2. What are my options for recent imagery? At ...
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2answers
200 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 ...
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1answer
194 views

Convert from Mercator to transverse Mercator projection in C++?

I'm writing code to import images from a WMS server into some software. However, the software expects the images to be in transverse Mercator, but the WMS server provides it in Mercator. This ends up ...
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1answer
200 views

How did Nova create the globes in Earth From Space?

Nova recently aired Earth From Space on PBS. (I highly recommend it.) Also found here on youtube. Produced in extensive consultation with NASA scientists, NOVA takes data from ...
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2answers
99 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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0answers
263 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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2answers
645 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
173 views

How to modify 2 raster images to have the same resolution?

I have data for 2 rasters images that have different resolutions: z downloaded from trmm An MSAVI2 output image. For calculating the correlation between them, the data has to be in the same ...
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0answers
124 views

ESRI imagery service that is WMS Compliant

I want to use the ESRI free online imagery service http://services.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer But I want a service that is WMS compliant. Is there a version of ...
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1answer
47 views

How to detect which Quickbird data product?

I have some Quickbird imagery, for further processing I would like to know what kind of data product are these images. The imagery only has an additional text file containing some order numbers. ...
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0answers
88 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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1answer
299 views

Atmospheric Calibration for Landsat 7 ETM+ Gap Filling

This is for thesis work involving mapping of above-ground mangrove forest biomass using Landsat 7 ETM+ imagery. I am assessing correlations between biomass with vegetative indices, e.g. NDVI, and ...
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1answer
301 views

Issues calculating NDVI from ASTER

I'm having an issue with ASTER data. I have two mosaics; one for 2008 and one for 2012. Both are composed of 4 ASTER scenes and the scenes are all from the same two month period (i.e. no seasonal ...
3
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1answer
283 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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1answer
859 views

How to adjust online basemap to Arcmap

How can I adjust the online basemap imagery file to our existing ArcMap data. Below are steps I perform to add the basemap data. I Added basemap from "Add Data From GIS Online" in the file menu and ...
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2answers
253 views

Pictometry Accuracy and/or Alternative

I'm looking for some insights into the accuracy (x,y,z) of oblique imagery from Pictometry in terms of providing accurate measurements for property evaluation. Is the high cost of this product ...
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3answers
1k views

How to crop a satellite image?

I am wondering how to or if it is possible to crop a SPOT satellite image (the image has black edges) using ArcMap 10 and if so how do you do this. I appreciate any advice.
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2answers
316 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?
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2answers
229 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 ...
3
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3answers
371 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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1answer
155 views

trouble with i.landsat.toar failing to identify satellite

I am trying to use the i.landsat.toar tool on L7 bands. I have tried to use both the MTL and MTLold, but no matter what I try, it returns "Failed to identify satellite." What am I doing wrong?
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3answers
2k views

Free Imagery WMS Feeds in QGIS

I was wondering if anyone knows of a free WMS of imagery that I could use within QGIS. The imagery does not have to be high resolution (Blue Marble even). I would like to have a base imagery feed ...
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2answers
664 views

What countries allow commercial use of drones to collect aerial imagery?

Currently the US government forbids commercial use of drones to collect aerial imagery. The FAA is supposedly reviewing this to determine what sorts of restrictions are needed to allow this to happen ...
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4answers
201 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 ...
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3answers
314 views

Where can I get aerial images for commercial use?

Related question: Free aerial map images for commercial use - Alternatives to Google maps I'm looking for a service that will allow me to download images at up to 1 meter resolution. Currently our ...
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1answer
422 views

Coordinate system in aerial imagery

I am calculating WGS84 coordinates of points in an aerial image, given the WGS84 coordinates of the center of the image and the ground distance width and height (calculated from altitude and lens ...
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2answers
361 views

How to perform enhancement operations on an satellite imagery in QGIS?

I am a new user of QGIS please suggest how to perform image enhancement operations on an satellite imagery like ratioing, contrast stretching, edge engancement, filtering etc. in QGIS?
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2answers
1k 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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1answer
188 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 ...
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0answers
211 views

Raster satellite images for QGIS

When I try to apply a downloaded GIS satellite (t=rimage to Quantum, it doesn't seem to open properly. There must be a step-by step description on how this would be done effectively. Can anyone tell ...
3
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1answer
206 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 ...
3
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1answer
202 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 ...
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2answers
360 views

Extract certain area of contours/satellite images

I have 2 satellite images (jpeg2000 format) and 2 xyz-files from the same area. I am trying to extract certain region from the area including contour lines and the satellite image in order to import ...
3
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2answers
105 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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1answer
28 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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2answers
1k views

How to equalise colour, brightness and contrast across several scanned paper maps

I am a vectors guy mostly, but for a current project I need to work with a bunch of old scanned paper maps (ww2 bomb damage maps for London, if your interested!) We scanned and georeferenced the ...
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0answers
476 views

Automated testing for GIS apps

There are several commercial and opensource tools for regression automation. While many of them could be employed to test GIS apps, they fall short, at times, dealing with the unique characteristics ...
2
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2answers
316 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 ...