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

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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
713 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
207 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
334 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
498 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
480 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
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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1answer
208 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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240 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
248 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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224 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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416 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
111 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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1answer
29 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
584 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
360 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
386 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
964 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
665 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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4answers
999 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
911 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
1k 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
278 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
301 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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384 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
613 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... using ArcGIS 10 Would also consider any of the ...
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0answers
82 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
571 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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2answers
6k 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 ...
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2answers
141 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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1answer
384 views

GDAL Brightness RGB Contrast Gamma Saturation

I've not had much experience with modifying imagery, I've recently been playing with GDAL for some batch processing of geo-referenced images, I've been supplied with some imagery in ECW format that is ...
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1answer
354 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 ...
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369 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.
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1answer
95 views

Is there an image service from GOES available for ArcGIS?

I have an arcmap project using an arcims service from NOAA ENC (http://ocs-spatial.ncd.noaa.gov) but maybe the service is unavailable right now and I can't access to imagery... Is there an image ...
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3answers
2k views

Poor image quality of raster pyramid files in ArcGIS (no anti-aliasing)

There are several GeoTIFF files (size ~7000x7000 px) which I try to open in ArcGIS Desktop 10.0. I have already created raster pyramids for them (.ovr files) using geoprocessing tool but their quality ...
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2answers
367 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 ...
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2k views

How to convert GeoTIFF to grayscale and add gaussian blur?

I have a giant GeoTIFF I'd like to convert to grayscale and add a gaussian blur to. As far as I know, GDAL can strip two of the three color bands and call it grayscale, which might work, but is there ...
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1answer
202 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 ...
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1answer
439 views

Is there any plugin for QGIS to calibrate contrast and brightness of a raster layer?

I frequently need to deal with the contrast and brightness of raster layers in QGIS and I miss the tools in ArcGIS for this task. Should there be a plugin already developed for QGIS? If there is, ...
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2answers
830 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 ...
4
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1answer
727 views

How to identify image location?

I have a satellite image of only one part of some city with a lot of vegetation. I need to find out where is that image taken. I'm interested is there any way to find out where it is taken on Google ...
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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 ...
5
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2answers
396 views

Which is the best way to create a polygon with the extents of a raster file in QGIS?

I have a tiff image file and want to get a polygon with the extent of the tiff. Is there a direct way of doing this? Right now i have to convert the image to vector (with gdal_polygonize) and then ...
3
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1answer
439 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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402 views

50cm imagery - aerial or satellite?

The area of interest is 1450 km2. My options are: 50cm newly collected aerial natural color imagery for $28,300 OR 50cm recent archival satellite imagery (includes near IR band) for $20,600 The ...
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311 views

Incorrect spatial extent for imported hdf image on ArcGIS

I imported an hdf image onto ArcGIS but I cannot make correct projection of it. Also, it does not have correct spatial extent (please see the enclosed figure, the small one is projected under WGS84). ...
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4answers
3k views

How to redefine the nodata value into zero in QGIS?

I have an image which i cliped with an AOI polygon. The contour area was set to pixel value = 0 and I have a nodata value of -32768. I want to redefine the nodata value into zero. I used to do this ...
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5answers
1k views

Georeferencing aerial photos when only centroid is known using ArcGIS for Desktop or ERDAS Imagine?

I have heaps of aerial photos that need to be georeferenced. I have access to ArcMap and ERDAS. All I am given is an excel sheet with the centroid coordinates of each image. Each photo covers ...