A representation or description of a scene, typically produced by an optical or electronic device, such as a camera or a scanning radiometer.

learn more… | top users | synonyms

7
votes
4answers
338 views

How to compare areas in scanned historical land use maps

I am a relative beginner to using GIS, and am running QGIS 2.0.1 in Linux. I have two historical maps which I want to analyze, that show land use patterns in the same area at two different moments in ...
7
votes
2answers
697 views

How to Georeference Photos With No Spatial Reference?

I have about 100-200 field ground shot photos I would like to overlay in ArcGIS 10 that have no spatial information which I need to somehow develop using a photogrammetric formula. The camera was ...
6
votes
1answer
2k views

Creating a mask with transparent pixels in python

I have a geotiff image with pixel intensities ranging between certain values. Lets say bewteen -2 and 2 (the image is normalized). I have a certain threshold which interests me, lets sat 1. I would ...
6
votes
3answers
534 views

How to generate image tiles from custom geo data for use with Leaflet

Migrating a webapp from Google Maps API V3 to OSM + Leaflet, which displays custom data that consists of lots of lines and points, on a background map. When this custom data is drawn by Leaflet on ...
5
votes
4answers
444 views

Is there a way to filter the colors out of an image?

I am using ArcGIS 10.2 to show a facility's size and position in a project area. I was not given any shape files or survey files of the area. I only have a deed (.pdf) with a B&W sketch of what ...
5
votes
2answers
557 views

How to display a lot of images with OpenLayers?

I would like to display a lot of images at same time. The images are georeferenced (they have extents), with some labels on top of it which, on click, open popup. I can not say how many exactly ...
5
votes
2answers
107 views

Retrieving heights of buildings using remotely sensed data (except lidar)

How can I get the height values of buildings from a certain sector a city without going into the field to collect data? Is there anyway to do via satellite imagery, SRTM, ASTER GDEM or any DEM for ...
5
votes
2answers
345 views

10 GB Raster Aerial Image in Quantum and POSTGIS

I have a problem... I have been successful in uploading the raster in postgis but when I access it through Qgis. it does not open even after several hours. I have 10GB aerial image raster and ...
4
votes
4answers
2k views

Free radar (SAR) satellite data

I'm looking for free (non-commercial use) sources of radar (SAR) satellite imagery. Does anyone know of sources?
4
votes
3answers
494 views

Software for opening .img files

I have some cpc precipitation data stored in IMG format.Could anyone suggest a software beside ERDAS imagine or Arcgis which can be freely downloaded?
4
votes
2answers
178 views

What Information Does the Blue Band Provide?

I am playing around with ERDAS and was implementing image difference on two rasters separated by interval of time. I was using a blue band raster and I created a default threshold for percentage ...
4
votes
2answers
391 views

How do I Capture GDAL projection and create matching output (OGR or GDAL) shape files?

Working in C++, using GDAL and OGR: Depending on what the user has supplied for image input, I need to output point (or other) shape files in the same projection as the input raster images. The ...
4
votes
0answers
656 views

I have a Web Application (ASP.NET) made ​​in ArcGIS Server Manager. How to create a button for the user to export his vision for PDF / Image?

I am using ArcGIS Server Manager to create Web Applications (ASP.NET). I would like the customer to access has an option to export your vision to PDF or Image, or both. I would like to generate the ...
3
votes
1answer
56 views

How to load multiple images with the same CRS?

When I add several images to QGIS 1.8 it asks the coordinate reference system for each one. There are several seconds in between the dialog and it is not easy to just continue working as the dialog ...
3
votes
3answers
1k views

Merge DEM and Hillshade to create one file?

I am wondering if I could merge DEM and Hillshade ? What is the pro and cons for that? Thanks
3
votes
1answer
726 views

Panchromatic Image association with high spatial resolution

How and Why is a Panchromatic Satellite Image associated with high spatial resolution? I googled and found that it is a single band image, but then why is it called pan-chromatic(All Colors). Does it ...
3
votes
2answers
309 views

How to create georeferenced and projected data from hand-drawn map?

I am preparing datasets for students in a spatial statistics course for a module on spatial autoregressive models. We will use ArcGIS 10.1. The first dataset will correspond to a mythical ...
3
votes
1answer
297 views

ESRI/ArcGIS draw protractor

I am using ArcGIS maps and trying to follow JS API. I am trying to understand how can I add a protractor on the map which will help in angles while drawing polygons. I understand I could add a Feature ...
3
votes
2answers
200 views

High resolution satellite

Can any one tell me from where I can buy commercial High resolution Satellite images for Biodiversity research ? I need some websites that sells these kind of images ?
3
votes
5answers
2k views

Automatically download and merge webmap tiles into one big image?

Is there an easy way to download a bunch of web map tiles (in /z/x/y.png format) and stitch them together into a single large image? I could probably script this using ImageMagick, but would prefer ...
3
votes
1answer
1k views

circle detection on binary image

My image is gray scale image which i have converted to binary by smoothing and then edge detection method. Now i want to place the circle /ellipse on edge detected. I don't know how to proceed ...
3
votes
1answer
583 views

Relative Hyperlinks in QGIS without end user's software dependency

I am trying to work out how can I add a relative path hyperlink to a shapefile in QGIS. I have found several great tips on various forums but only one has so far potential to be implemented. The ...
3
votes
2answers
2k views

Is it possible to add a simple image or graphic to the map canvas?

Is it possible to add a simple image or graphic to the map canvas in QGIS (e.g. a symbol marker)?
3
votes
2answers
1k views

How to save MapServer output to a file?

How can I save the results from a MapServer file as an image? I would like to be able to write a png file as a result of a query. My query which I can display in browser is the following: ...
3
votes
0answers
38 views

Automate Exporting of Rasters Using Renderer in ArcGIS

It is possible to export rasters in ArcMap by right clicking the layer-> Data-> Export: You can then click 'Use Renderer' check box to ensure the image you export uses the current ...
3
votes
0answers
353 views

Convert land-based camera image pixel x,y to ground lat/long or x,y,z

I have a number of cameras at various known locations (x,y,z) and directions that are above ground about 20 feet pointed at different ground locations about 100 feet away from each camera, and whose ...
3
votes
0answers
221 views

How to read pixel values from an image server layer with ArcObjects?

I'm having a problem with reading pixel values from the image server layer. The image server layer class implements IRasterLayer, so when I tried to read pixel values using IRaster2 obtained through ...
2
votes
3answers
65 views

Turn latlngs into image file?

I have a huge CSV file of WGS84 latitudes and longitudes, and I would like to turn these into a large image file that I can print (with each point being a pixel on the image). What is the best way ...
2
votes
4answers
646 views

Determining which “color” each image band represents?

I have a satellite image that has a few bands in it. But I don't know what colors they are supposed to represent, nor do I know where to look for this information--the file's metadata say nothing ...
2
votes
2answers
860 views

Leaflet.geojson webpage performance out of hand, how to convert to .png?

I exported some countries as a single .geojson file. The file includes every country's vertices and coordinates, as that's what a .geojson is ─ a vector file. Thing is, there are about 20 countries ...
2
votes
1answer
2k views

Convert X Y Pixels to Easting Northing

I'm trying to find out what the formula would be to convert the X, Y of an image to the Easting and Northing coordinates. I've downloaded some of the raster maps from OS UK web site and I'm looking ...
2
votes
1answer
155 views

Sort colors from light red to dark red

I have the following png image displaying tanker traffic density: The colors are from dark red to light red, dark red means 'lowest density' and light red means 'highest density'. For example, the ...
2
votes
1answer
642 views

How to Determine to world map size in pixel given this data?

How to Determine the world map size in pixels given this data? Map size of a particular area say, for example: Makati city, Philippines with bounds: Top-Right: 121.0281, 14.56497 Bottom-Left: ...
2
votes
1answer
730 views

How to have a layer with many images that scale?

I know that in OpenLayers you can add Features to a Vector Layer which each have image but then they will not scale (i.e. their size stays the same independent of the current zoom) or at least I do ...
2
votes
1answer
98 views

ArcGIS Report with images based on a field

Just a quick question for all the experts out there. I'm currently trying to generate a report through ArcGIS 10.2.2 based on my attribute table in which one of the field is a photo links field. I ...
2
votes
1answer
149 views

Determining the transformation between a satellite image and long/lat

I'm trying to overlay some data onto a satellite image of the UK. The image is a hi-resolution version of the image below (originally from dundee university): ...
2
votes
1answer
1k views

Added PNG dissapears when I export/print map

Ive added a PNG image of a chart to my map and when i try to export as any image file or print the map the PNG image is not there. Im using arcmap 9.3. in layout view im adding image which ive tried ...
2
votes
1answer
49 views

Cache - how to give QGIS more?

Another question... how do you increase Cache size? think QGIS is falling-over as haven't given it enough... image to export 1080 x 800 mm! would like at least 120 dpi or 200 : ) Many thanks, Cas
2
votes
1answer
38 views

Georeferencing an image to a Progressive JPEG

I am using the Georeferencing tool in ArcGIS 10.2 to georeference a normal JPEG image. I want to produce a georeferenced Progressive JPEG image from that image, but there is no JPEG Progressive ...
2
votes
1answer
120 views

Extract all unique values from a RGB raster

I have a .png file in RGB format showing the intensity of ship traffic: For my analysis I need to convert it to a one-band raster with values between 0 and 1 where 0 means lowest density and 1 ...
2
votes
1answer
170 views

Spot 6 - Reflectance calibration

I have a Spot-6 image and the metadata contain 9 values of SUN_ELEVATION (BottomRight BottomCenter BottomLeft CenterRight Center CenterLeft TopRight TopCenter TopLeft). I've used before Landsat and ...
2
votes
1answer
200 views

Create image (TIFF/PNG) from geodetic (lat/long) data

Using Java, I need to render a bunch of geodetic data to an image, ideally TIFF or PNG. Specifically this is weather data, with each sample having a latitude, longitude, and amplitude value. I'd like ...
2
votes
1answer
297 views

Can I edit pixels values of an image with GDAL?

There is a method with GDAL (used in C/C++) to edit pixel values of a georeferenced image, maintaining the original file? Or I have to create a new dataset? My goal is to maintain ALL originals ...
2
votes
1answer
122 views

How to determine if an image file is georeferenced

I have a task to scan a folder for georeferenced images. There might be a lot of images, some quite large, and some not georeferenced. The spatial information can also be either embedded or in a world ...
2
votes
1answer
144 views

Adding images to placemarks multiple times

I have a route that I travel that is saved by coordinates to a .csv file for use in GE. I have images (pictures) that I would like to add to placemarks I have along the route. Is there a script or ...
2
votes
3answers
5k views

help displaying jpg in openlayers?

I am trying to overlay a jpg image over an openlayers map. I have been to the example on their site and looked all over for a solution with no luck. So I am guessing that their are rules for setting ...
2
votes
0answers
51 views

Is it possible to get coordinates for point from satellite image? [closed]

Is it possible to get coordination for point from satellite image using any programming language? For example, if I clicked on a specific point on a satellite image hosted on a web application, I ...
2
votes
0answers
81 views

ArcGIS for Desktop is rotating attachment pictures from feature service of ArcGIS Online?

I have a web map on my ArcGIS Online account. In that map are features (line polygon points) with a picture attached to each feature. After saving the feature service as a local copy on my desktop ...
2
votes
1answer
47 views

Cannot save map from composer as image or pdf

I have created a map and made a nice lay-out in the printer composer (in QGIS 2.4), the weird thing is, that if I try to save my map as an image or as a pdf immediately after entering the name in the ...
2
votes
0answers
91 views

multiple image in OpenLayers

I'm fairly new to OpenLayers so please bear with me. I'm trying to add multiple images to OpenLayers. I have the following (some code is excluded): var images = [image1,image2,image3] // these are ...