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

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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
292 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
156 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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588 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
2k 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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2answers
256 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
375 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
94 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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113 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
455 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
553 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 ...
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1answer
638 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
2k 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
388 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
2k 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
561 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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2answers
555 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
816 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
177 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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4answers
4k 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
907 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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2answers
530 views

Calculate potential of solar radiation on rooftops (without LiDAR data)

I'm trying to calculate the solar radiation for rooftops, but I have a big problem, I don't have LIDAR data. I need to give the buildings the information of height. I've tried to do these, but for a ...
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4answers
252 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
446 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
775 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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1k 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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3answers
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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
317 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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325 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 ...
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1answer
368 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
282 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
556 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 ...
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2answers
153 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?
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36 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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2k 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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880 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 ...
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2answers
514 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 ...
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1answer
610 views

Is there a way of viewing a photo has a point tag from Photo2shape in QGIS?

Is there a way to view images (photos) that have location point from Photo2shape by clicking on the point in QGIS?
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4answers
2k views

Where can I download free satellite imagery of Cambodia for offline use?

I am an entry level GIS user - I have had one semester of GIS in college. I have successfully downloaded raster satellite imagery from Seamless (tiff files) for my class project. Now I am trying to ...
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3answers
1k views

Alternative vegetation indices

I have been using NDVIs with limited success to identify trees in the central Great Plains region of the USA. The problem I have been encountering is that reflectance from farm fields/pastures have ...
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5answers
2k views

Visualization of satellite image - directly in python

Is there any way (a package or what not), to visualize a geotiff image directly in Python? I don't want to use ENVI or ArcGIS or anything else. Thank you in advance.
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1answer
1k views

Convert 3-band raster imagery to distinct vector zones in ArcGIS

So much like the title says I would like to convert a 3-band infrared image TIF file of vegetation into distinct vector feature zones using ArcGIS. I'm guessing the only way to do this is with ...
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2answers
2k views

Creating a multispectral image from scratch

I want to make a multispectral image from cero to do some tests on it. Something really simple like 5 completely uniform bands with salt and pepper noise on them or a square of different values at the ...
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2answers
400 views

Wavelet vs Discrete compression for imagery

What is the main reasons to choose wavelet (jp2, sid, ecw) instead of discrete (JPEG) compression methods for raster data? Lets limit this question to aerial imagery and lossy compression. Why ...
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3answers
428 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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2answers
519 views

Purpose of building footprints

What are the uses (public and private industry) of building footprints? I'm trying to figure out how polygon building footprints can be used. i.e. are they used for determining tax liabilities, ...
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3answers
837 views

Looking for high resolution (1m or better) aerials for Turkey?

Would prefer free but under a couple hundred dollars is also doable. It would be nice to have actual tif, sid, etc. files but a WMS would also work. The WMS (bing and esri) I have been able to ...
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0answers
93 views

Are there any naming conventions for aerial imagery?

Do GIS projects involving high resolution NAIP quarter quad imagery typically use the USGSID code and qq (e.g. 3910232ne) or the GNIS code and qq (e.g. 39102e1ne) to organize data? I can't seem to ...
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3answers
710 views

Combine aerial imagery pictures to create a layer

We are looking for software or a web service that we can put in pictures we took using our weather balloon to create a single image, that we can use as a layer for our GIS project. Preferably free, or ...
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3answers
11k views

Where can i download a good World image in GeoTIFF?

I can either be from MERIS (ESA) or from MODIS (Nasa). I already reached these sites: http://www.unearthedoutdoors.net/global_data/true_marble/download ...