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

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7
votes
4answers
253 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
452 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
1k 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
215 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
2answers
460 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
318 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
3answers
259 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
156 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
326 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
544 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
52 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
882 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
229 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
5answers
954 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
2answers
616 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
2answers
210 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
403 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
782 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
223 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
183 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
4answers
171 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
1answer
349 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
375 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
1k views

Convert X Y Pixels to Easting Northing

Hopefully someone can help. 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 ...
2
votes
1answer
587 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
34 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
123 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
2answers
1k 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)?
2
votes
1answer
728 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
128 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
106 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
135 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
4k 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
29 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 ...
2
votes
0answers
36 views

Can a DXF File contain raster images (TIFF/JPG)?

I am maintaining a large Program with a graphical editor. Our Program can export DXF and it can show Background Raster Images of various types (TIFF, JPG, BMP etc.). Is it possible to embed these ...
2
votes
0answers
279 views

How to extract road line pattern from satellite images using Matlab? [closed]

Firstly we applied canny edge detection to the image, then detected lines using houghlines, then we got start and end points of the lines. Then we applied delaunay triangulation and voronoi diagram ...
2
votes
1answer
102 views

QGIS image export changes the map center and scale

I've been trying to export a few map layers using QGIS print composer. First, I loaded the layers and opened the composer using Project -> New Print Composer: Gave it a proper name: Added a ...
2
votes
0answers
73 views

Flood extent extraction from satellite images

How i can extract the floodwater from satellite images? Is the image classification method accurate for moderate-resolution satellite (Terra/Aqua MODIS)? Or is there a more accurate methods? Thanks.
2
votes
0answers
77 views

Adding dynamic picture elements to mapbook [closed]

I have a feature class full of traffic signal data including up to 3 pictures of each traffic signal. I want to create a series of data driven pages that include 3 picture/data frames that ...
2
votes
0answers
475 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 ...
1
vote
2answers
778 views

Merging many rasters using Python

I have a list of many many rasters. I want to have a simple and easy to understand script that takes this and merges it into one big mosaic. I found a similar question but the accepted answer adivises ...
1
vote
2answers
131 views

Where to find Icon library for custom GIS software?

I am building a desktop application and currently utilizing a mix of icons for pan, select, zoom, attribute table, etc that have been randomly taken from the internet and modified. The overall look ...
1
vote
1answer
74 views

How to convert jpgs to RST for IDRISI Selva Image Processing

I would like to create a mosaic data set in IDRSI Selva however, my images are jpg. Is there a way to convert these within IDRISI or otherwise? Thanks.
1
vote
1answer
47 views

image rectification with Mercator projection

I have written an image rectification function which allows a user to select 2 points on an image and 2 points on a map. The function will then rectify the image so it is translated, scaled and ...
1
vote
1answer
60 views

Katalog for Envi

I am working In Process of Image Cataloging of Satellite Imagery. For That I have found Free extension software in ENVI called "KATALOG" .But I cannot find any useful resources for Downloading it. ...
1
vote
2answers
2k views

How to display a image from Postgres database

I have Images in bytea form in PostgreSQL/PostGIS database, i want to display them in a webpage using PHP - PostgreSQL. I got lot of examples and I worked out but not getting output from them... Few ...
1
vote
1answer
1k views

Overlay the big map image with Google Maps API

I put the image on my website with overlay option in Google Maps API. But the map image which is overlayed is too big: 2.85 MB. I can't resize it, so I wonder is there an option to put it somewhere on ...
1
vote
1answer
51 views

Which wavelengths are assigned to which bands in NAIP imagery?

I cannot seem to find a definitive source on which wavelengths are assigned to which bands for 4-band NAIP imagery. Here is an example of the imagery I am working with (2011 4-band NAIP imagery). I ...
1
vote
2answers
92 views

Permanently attaching Image file to Feature Class in 10.1

I need to forward on a File Geodatabase, and I am using the attachment manager to attach the file images associated with the different features in my Feature class. If I forward on this FGD, will the ...
1
vote
1answer
151 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 ...