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Questions tagged [image]

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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18
votes
1answer
32k 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 ...
10
votes
5answers
26k views

Free radar (SAR) satellite data [closed]

I'm looking for free (non-commercial use) sources of radar (SAR) satellite imagery. Does anyone know of sources?
10
votes
3answers
3k views

Rendering images in OpenLayers?

My organization has a web application for displaying global and regional climate data and we're considering improvements to it. Our leading idea is to create an OpenLayers-based application to ...
10
votes
4answers
1k views

Comparing areas in scanned historical land use maps using QGIS?

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 ...
9
votes
2answers
1k 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 ...
8
votes
2answers
16k views

image segmentation of RGB image by K means clustering in python

I want to segment RGB images for land cover using k means clustering in such a fashion that the different regions of the image are marked by different colors and if possible boundaries are created ...
8
votes
1answer
127 views

Creating vector (with lines/polygons) from raster based on paper map in QGIS

For a task I have several maps created with GIS that look like the following: I am mainly interested in the colored zones that aren't roads (red) or rivers (blue) and would like to turn these into ...
8
votes
2answers
2k views

Georeferencing 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 ...
7
votes
3answers
2k views

Seeking 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?
7
votes
6answers
9k 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 ...
7
votes
2answers
628 views

LiDAR intensity image from multiple flight lines?

I'm working with multiple raw las tiles, and I've used Fusion to create an intensity image, but it shows the flight line overlap (see below). Any idea how can I smooth the image so that the overlap is ...
6
votes
4answers
2k 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 ...
6
votes
1answer
4k views

Creating a mask with transparent pixels in Python

I have a GeoTIFF image with pixel intensities ranging between certain values. Let's say between -2 and 2 (the image is normalized). I have a certain threshold which interests me, let's sat 1. I would ...
6
votes
2answers
3k views

Detecting overlapping blobs in image?

I have read the following two posts related to my question; however, my problem is slightly different and I'm having a hard time solving it. Finding if two polygons Intersect in python? Getting ...
6
votes
1answer
4k views

How to export the map in very high resolution

I made a map in QGIS. Now I want to export the resulting image (layers upon layers) for further processing in GDAL. The print composer only lets me export an image up to a fixed size. If I try to ...
6
votes
1answer
622 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 symbology/rendering ...
6
votes
3answers
2k 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 ...
6
votes
1answer
1k 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 ...
5
votes
4answers
472 views

ArcGIS 10.3: Insert rotated image without background

How can I insert this image into an mxd so the white background doesn't show up? I've tried using photoshop to delete the background and save it as a format that supports transparent backgrounds (gif ...
5
votes
2answers
5k 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 ...
5
votes
2answers
1k 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 cannot say how many exactly because ...
5
votes
1answer
5k views

Creating scatterplot with icons (svg or png) instead of points?

I'm just starting with R and I wanted to know if it's possible to create a scatterplot with custom icons (svg or png) instead of points. I started to import a shapefile, and then I have a set of ...
5
votes
2answers
12k 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)?
5
votes
3answers
740 views

Is it possible to export my FME workbench canvas as a JPEG?

I want to print my FME workbench to a JPG so that the entire canvas is in one image. I have tried printing it to a PDF but it is trying to put it on multiple pages. I have even tried setting the ...
5
votes
1answer
445 views

How can I achieve high quality supervised classification?

For the supervised classification I use: QGIS, Semi-Automatic-Classification Plugin, a Landsat-8 Satallite Image and the CORINE Land Cover classes (http://uls.eionet.europa.eu/CLC2000/classes/...
5
votes
2answers
490 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
517 views

I cannot find full Sentinel-2 scenes

I want to download Sentinel-2 images of "Navarra" zone from June to December of 2016. I want to download all swith image (all tiles in a SAFE file) but when I search this I only can download up to ...
4
votes
1answer
2k views

Is the reflectance required to get the NDVI, for Landsat 8 images?

I'm a beginner in satellite optical imagery. I have a landsat 8 image (11 bands downloaded from http://earthexplorer.usgs.gov/) for which I need to calculate the NDVI (Normalized Difference Vegetation ...
4
votes
2answers
617 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
1answer
244 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 ...
4
votes
1answer
941 views

Otsu thresholding and classic image processing algorithms on radiometrically calibrated Sentinel-1 SAR images

Is it possible to apply the Otsu thresholding (or any other image processing algorithm dedicated to image digital values in the interval [0, 255]) to a Radiometrically calibrated Sentinel-1 SAR ...
4
votes
3answers
3k views

Merge DEM and Hillshade to create one file?

I am wondering if I could merge DEM and Hillshade? What are the pros and cons for that?
4
votes
1answer
398 views

Embedding Images in map layouts and documents (*.mxd)?

I wanted to place some images in my map layout but I found that images are not embedded in the MXD files so now, after I deleted them, I've lost the graphics and have to do them again. Is here any ...
4
votes
2answers
678 views

Creating georeferenced and projected data from hand-drawn map using ArcGIS Desktop?

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 pre-...
4
votes
2answers
1k views

Capture GDAL projection and create matching output (OGR or GDAL) shapefiles?

Working in C++, using GDAL and OGR: Depending on what the user has supplied for image input, I need to output point (or other) shapefiles in the same projection as the input raster images. The ...
4
votes
2answers
4k views

Saving MapServer output to 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: http://...
4
votes
1answer
4k views

Put png map image as a background to draw upon

I have an image of a fiber optics network map: I want to turn this map image (without any actual GIS data) into a vector map where each point is defined by lat, long. To do this, I'm trying to ...
4
votes
1answer
232 views

Select feature one by one and save it as image

I have used following code for selecting the features and save it as image. layer = self.iface.activeLayer(); layer.setSelectedFeatures([]) count =layer.featureCount() lstChalta = [] lstFeatures = ...
4
votes
0answers
38 views

Displaying images as part of multiattribute labels using QGIS

I would like to display images referenced in an attribute column as part of a multiattribute label, so that I can eventually print them with the map. I do not want to display geotagged images, since ...
4
votes
0answers
1k 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
2answers
5k 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 adivices ...
3
votes
3answers
3k views

Adding excel table to QGIS print composer?

Can anyone suggest some ideas to add a excel table to the print composer which will then be exported as a A3 png while retaining resolution. Attempted pasting in word as an enhanced meta file then ...
3
votes
4answers
6k views

Multi Temporal Images

I am new to remote sensing, so I would want to clarify my understanding of the meaning of Multi Temporal Images. As far as I understand, multi temporal images are multiple images of the same scene ...
3
votes
3answers
518 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
2answers
801 views

How to drape image on surface using open source software?

I have a image with a known projection - say an aerial photo. I also have a raster surface grid with the same projection - say a DEM. Both are in the same projection. Both have the same extent. How ...
3
votes
1answer
3k views

How to Read&Write .tiff images in java using GDAL library

I searched many sites to learn about this but I didn't find anything. I need step by step process for reading .tiff monochromatic image in java using Gdal library.
3
votes
1answer
104 views

Down sample with imagemagick then import worldfile?

I'm trying to get a better understanding of the limitations of world files and how I can use them in a current project. If I produce an ESRI world file (tfw) with listgeo: listgeo -tfw clip.tif ...
3
votes
4answers
8k 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 ...
3
votes
1answer
2k 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
1answer
606 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 ...