Raster is a data format consisting of regular grids of values, usually stored in an image-like format.

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MapServer map file shows Raster image as white

I'm using PAN image for raster publishing but the output in browser shows a full white image? Please give me the solution? My map file is ass follows: MAP NAME "terra" # Map image size SIZE 600 600 ...
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1answer
89 views

Calculating road density in R using kernel density

I have a large (~70MB) shapefile of roads and want to convert this to a raster with road density in each cell. Ideally I'd like to do this in R along with GDAL command line tools if necessary. My ...
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1answer
46 views

Error adding MrSID raster layer to QGIS for Mac OS X 10.10.2 (Yosemite)

I want to add a MrSID layer to QGIS (version 2.6.1) with a computer running Mac OS X Yosemite. I installed QGIS through macports from the terminal and all python packages through macports, as well. I ...
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2answers
30 views

Dealing with NoData Values in Arcgis

I have a set of rasters which I want to calculate mean of them,these rasters has some NoDate values,I have two approaches first using this code in raster calculator I interpolate them ...
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1answer
61 views

Removing salt and pepper effect

In a land cover raster (categorical map) that is a product of classified satellite image, what is the best way to remove "salt and pepper" effect from the image after classification. I am not ...
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1answer
18 views

How to turn a vectorgraph into raster correctly?

In QGIS2.8 version, I added several points in a point vectorgraph. When using the grid - > Conversion - > rasterized vector , The results turn out into a black figure. How to turn a vectorgraph into ...
3
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4answers
186 views

Convert line shapefile to raster, value=total length of lines within cell

I have a line shapefile representing a road network. I wish to rasterize this data, with the resulting values in the raster showing the total length of the lines that fall within the raster cell. The ...
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2answers
32 views

Combine overlapping rasters and include cells with no data

I'd like to combine about a dozen rasters into one raster that contains the "summed" cell values where overlaps occur. In doing so, I need to be able to retain cells that either have no data, or that ...
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2answers
23 views

Merging raster data in QGIS using wildcards

I have a problem merging raster data sets in QGIS, and I have searched various forums, but have not found a solution yet. An "ordinary" merge, for example merging the raster files ...
0
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1answer
131 views

Issues calculating range with QGIS 2.0 raster calculator

I would like to calculate a simple range using the QGIS 2.0 Raster Calculator, but am getting strange results. I believe I am not using the correct syntax. To get all values between .003-.5, I ...
2
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5answers
282 views

Greyscale Raster (tif) in ArcMap

I've searched all over google and have found nothing. I want some tiff files I have in ArcMap to be in greyscale with the rest of the layers in colour, similar to the style override > greyscale option ...
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2answers
678 views

Calculate area covered by a particular raster layer within polygons in QGIS

I am trying to extract information on vegetation cover within a set radius of point locations (my sites). I have succeeded in creating a new vector layer of circles with a 5 km radius around my sites. ...
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2answers
679 views

GDAL/proj4 equirectangular projection coordinate system units assumed by OGRSpatialReference and GDALDataset::GetGeoTransform()?

How do I configure my OGRSpatialReference object to specify an equirectangular projection system http://en.wikipedia.org/wiki/Equirectangular_projection where the affine geo-transform matrix (provided ...
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1answer
41 views

Coordinate system ID ArcGIS

I have satellite image files with metadata generated from ArcGIS: Raster Download Information Coordinate system ID WGS84: 4326 Top edge WGS84: 35.0003681085064 Degree Bottom edge WGS84: ...
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1answer
33 views

Conditional statement, apply different equation based on raster value R

I am trying to find the best way to apply a set of equations to a raster conditional on values in a separate raster. For example, suppose r1 has the values of interest and raster 2 (r2) is a raster ...
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1answer
34 views

Convert a lat, long, value table into a raster

I would like to to convert a table with latitude, long, and a value into a raster. My file looks like this: X Y Z 32.85138942 -6.643054718 0 32.85138942 -7.059721474 1004 32.85138942 ...
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1answer
56 views

QGIS 2.8 Convert a vector to a raster layer

When I change a vector layer to raster using raster button->converse->Vector rasterization in QGIS2.8. I get only a black picture. Why is that so and how can I convert a vector layer to a raster ...
2
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1answer
27 views

Loading Raster using QGIS API in Windows

I am trying to develop a C++ application using QGIS. I have to load a tif file and show it. First I wrote an app similar to samples on the internet. It works on Linux, but it does not work on ...
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2answers
24 views

How to compute climatology of 3 days moving averages for rasters pixel by pixel?

I have one year of datasets that I want to compute the climatology of 3-day moving averages and then I subtract this climatology from the original values for each pixel. example: # Set up the ...
2
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1answer
182 views

Spectral profile (z-profile) viewer for ArcGIS

I have multilayer raster with 6 bands. Is there a way to select one specific pixel and to display the z profile (the values of each band) for this pixel as a chart or table? I am looking for a tool ...
5
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7answers
4k views

How can I align two non-coincident equi-resolution raster grids?

I have two rasters: a digital elevation model (DEM) and a Landsat band. The grid resolution of both is 30 m, but the grids are not coincident (see image: the dark raster on top is the DEM; the light ...
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2answers
110 views

QGIS raster calculator using abs() function

Is it possible to use the Abs() function in the raster calculator in QGIS? I've tried it, but it didn't work.
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1answer
38 views

Qgis raster calculator not giving output

I want to calculate some result using QgisRasterCalculator and using the code mentioned below.Problem is i am not getting any output raster also if i use this formula in raster calculator it gives ...
2
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1answer
732 views

Problem in importing raster data from PostGIS to Geoserver

I am using Opengeo Suite 3.0.2, PostGIS 2.0.3 and PostgreSQl 9.2. I am trying to import raster data from PostGIS to Geoserver but facing an error. I follow this tutorial link to import the raster ...
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1answer
83 views

Why are raster z-values changed when reprojecting?

I have raster data with height values (z). When I try to reproject/warp the raster to Gauss Kruger 3, the z-values are changing (several meters). (The data is already GK3, but I have to reproject ...
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15 views

Creating raster from points that conforms to a reference geometry using PostGIS, python, QGIS

Please forgive my ignorance, I'm fairly new to processing GIS data. My bread and butter is statistics but I'm now working on a project that requires more data preprocessing and cleaning than I've ...
3
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1answer
69 views

Unsupervised classification in QGIS

I was trying to learn unsupervised classification in QGIS 2.6 following the tutorial video: https://www.youtube.com/watch?v=mI80eENtWSE When trying myself, clicked Run during the process it shows the ...
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2answers
3k views

How to visualize grd files in QGIS?

How to visualize grd files in the software QGIS?
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0answers
19 views

Overlay polygons on raster in different projections

I'm overlaying polygons on a raster to get the average value inside the polygon (using SAGA->Shapes-Grid->Add grid values to shapes in the QGIS Processing Toolbox), using a geographic and a ...
0
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0answers
14 views

Weighted Overlay not showing all values

In a ModelBuilder, my final step is to add a weighted overlay at the end. I have 4 reclassified layers as the input, all equally weighted and all contains values 1-10. However, when I run the Weighted ...
2
votes
1answer
351 views

USGS GeoTiff extent via GDAL

I have 2006 land cover GeoTiff from the USGS site (for a county in VA, USA). The projection is Albers Conical Equal Area Units. The download came with an HTML metadata file that tells me the geo ...
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1answer
30 views

QGIS how to save loaded min/max values for raster layers?

I am working with many layers. Each time I open my saved project, I must reload the min/max (properties/style) values. Is there a way to turn off the default 2% cut?
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1answer
435 views

Histogram Matching Python

I am trying to do histogram matching using Python to improve the mosaicking process of multiple overlapping rasters. I am basing my code on that found at: ...
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34 views

Project Raster Data Loss - 2 Billion People

I am using the SEDAC/CIESIN raster data for population counts. This data is in WGS1984, and I want to project this data to a Fuller projection. After running through "Project Raster" in ArcMap 10.1, ...
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8answers
8k views

How do I create a shapefile showing footprints of Rasters?

I have around 1,000 satellite images in tiff format, and I want to create a shapefile which will serve as an index to the rasters. This is something similar to a raster catalog, but I do not want to ...
0
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1answer
23 views

Creating an R factor raster in RUSLE Soil Loss equation with multiple input rasters

I am attempting to obtain the rainfall erosivity "R" factor for the RUSLE Soil Loss equation using rainfall PRISM 30 year history data. I have both monthly and annual data that comes into ArcMap as ...
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2answers
81 views

Multiply Rasters from two subfolders

I have two subfolders with Rasters named with the same parameters. I am trying to figure out a way to Loop a multiplication of each raster into a folder with its pair of the other subfolder. Looks ...
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1answer
22 views

Raster Calculator or Local-Combine tool? (in ArcPy)

i have 3 classified rasters and i wanted to use the following query from r. calculator: (rclslope>=45) & (rclmosaic>=2000) & (rclfocal>15) to arc.py how can i write it? Is it ...
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2answers
79 views

How to load projection along with raster in R?

Why the operation myraster = raster("test.asc") does not load the associated projection file test.prj located in the same directory as test.asc? Does raster() need a specific argument? It seems ...
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2answers
31 views

Zonal histogram for each region (row) in a polygon (table) with python script

I have DEM.tif (symbology uses equale interval - 100m) and a polygon file (regions.shp) with many regions (names are defined in 'reg_name' column). I would like to use Zonal Histogram to produce ...
2
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1answer
91 views

Reprojecting a raster image using gdalwarp

I am trying to reproject an ECW Orthophoto from 25830 to 23030 srid. I tried the following but I am getting an error: C:\Program Files (x86)\FWTools2.4.7>gdalwarp -s_srs 25830 -t_srs 23030 ...
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0answers
29 views

OpenLayers/Geoserver - can I create a tiled, zoomable raster layer?

Still a relative newbie with Geoserver and OpenLayers. Developing an application with Geoserver in the back, OpenLayers (3.0) in the front. I have a requirement to display imagery on top of a base ...
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1answer
23 views

how can I make “weighted sum overlay analysis” in QGIS? Ordered Weighted Averaging manual may be useful

I have weighted raster data converted from polygons with different categories. I have ArcGIS with 3D Analyst extension, unfortunately do not have Spatial Analyst, and I would like to use QGIS to make ...
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0answers
16 views

Reprojecting a ECW raster with fwtools [duplicate]

I have a ECW Orthophoto and i want to repoject it from 25830 to 23030 srid. I haven´t found a free software to do this but i heard of a command line utility called FWTools that could do the job. I ...
4
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1answer
55 views

How can I identify lines that intersect a certain raster layer area?

How do I identify certain roads ( of a line shapefile) that intersect with a layer that is produced from the reclassify tool (for raster data)? I am trying to identify which roads specifically are in ...
2
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2answers
672 views

Clip_management to raster extent outputs larger raster than raster extent

Using Python and ArcMap 10.0 SP5, I'm trying to reproject and clip a large input raster to exactly the same grid as a smaller target raster (same extent, pixel sizes and projection). The problem is ...
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2answers
23 views

Aspect Patch Count

I am using ArcMap to create aspect maps. I want to find the how many different directions the land faces (total aspect patch count) with continuous patches greater than three. So for example I want ...
3
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1answer
3k views

How can I compute raster pixel width and height given raster bounds, row count, and column count?

Restated, how do I convert arc degrees to meters? For example, I have an elevation data raster that has the following metadata: WEST LONGITUDE=64.97798789° E NORTH LATITUDE=33.02003415° N EAST ...
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0answers
27 views

Point to Raster Converting Result

I had a problem with Point to Raster converting result. I had an Excel file which contains x, y and z values. I wanted to create an individual raster data from classified z values so I planned to use ...
2
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2answers
1k views

Why is Raster Layer not visible?

I have a raster dataset that is not visible in Data View, but it is listed in the Table of Contents. I have tried viewing it in ArcCatalog but it is not visible there either. Is there something I ...