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

learn more… | top users | synonyms

1
vote
1answer
440 views

Building attribute table from raster in ArcMap 10.1

I have a NetCDF file containing the latitude, longitude and porosity for the entire US. I am trying to add another value (wilting point) which depends on the porosity. I wanted to extract the netcdf ...
0
votes
0answers
83 views

Dates are off when opening netcdf file in R

I have a netcdf file with the time dimension that goes from 12/2007 until 12/2010 with monthly time steps. I can see the correct dates in both arcgis and panoply. Panoply tells me this file is a ...
0
votes
1answer
211 views

Cannot read postgis RASTER into ArcGIS using the interoperability extension, either directly by Query Layer

This post accessing postgis raster data using Query layer in ArcGIS was created in Jul-12. Since then, I have not found any other related-post published. Using QGIS with DBManager ON, my postGIS ...
0
votes
1answer
479 views

How to load Georeferenced Scanned Maps in R

I have a geo-referenced scanned Map in GeoTiff format, which I would like to load into R. My intention is to plot some vector data (points and polygons) over this map using maptools package. Is ...
2
votes
1answer
237 views

Cannot upload an IMG file into PostGIS using raster2pgsql

I cannot upload into PostGIS a raster with the following code: raster2pgsql -s 4326 -I -C -M "C:\lyr\gebco.img" -F public.gebco ¦ psql -d test -U postgres -W It says ERROR: Unable to read raster ...
2
votes
0answers
124 views

How to display images as cross sections in 3d

I want to display a base map and several vertical cross sections in 3D. The base map image is easy to rectify as a geotiff. How can I also display the cross sections? The cross sections are at ...
0
votes
1answer
25 views

How do you distribute values evenly within zones when converting polygon to raster?

I'm trying to convert a (traffic analysis zone) TAZ polygon to raster so that the population values are evenly distributed within each zone. So far, when converting the TAZ polygon, the same ...
0
votes
2answers
59 views

how to specify -t critical dowloading raster with raster2pgsql

I'm trying to download a raster into postgres/postgis. So far I wrote: raster2pgsql -s 3006 -I -C -M -R filename.tif -F -t 463.313x463.313 schema.rastername | psql -h localhost -U postgres -d db ...
2
votes
1answer
54 views

does Pseudo Mercator Projection causes problem while clipping rasters

I tryed to clip a Raster file using an ESRI shapefile using gdalwarp command, but i always get an empty output file or a wrong clip with wrong location. this the command bellow: gdalwarp -dstnodata ...
21
votes
6answers
967 views

How to buffer raster pixels by their values?

The pixels to the left represent tree locations and their associated crown radii (i.e. pixel values ranging from 2 - 5). I would like to buffer these raster pixels by their crown radius value. The ...
0
votes
0answers
53 views

Publish rasters stored in PostGreSQL with GeoServer [duplicate]

we are trying to publish some raster images stored in our Postgres database. First, they were generated from satellite images (spectral indexes). Then we uploaded them with raster2psql as tables. So ...
3
votes
1answer
223 views

QGIS - How can I convert a raster file to a vector file without making same value cells into one polygon?

How can I convert a raster file to a vector file without making same value cells into one polygon? In the attached image, the values "2124", "2269", "2321", "2634", and "2920" are the polygons ...
2
votes
1answer
571 views

how to extract a variable at specific time and depth from netcdf in r

I have the following netcdf file containing 7 variables and 4 dimensions. [1] "file data.nc has 4 dimensions:" [1] "depth Size: 12" [1] "time Size: 37" [1] "x Size: 305" [1] "y Size: 432" ...
0
votes
1answer
62 views

QGIS problems getting layers to line up correctly.

I am trying to add a raster layer and a vector layer to qgis. I have set both of their CSR to NAD83 Oklahoma North State Plane. It doesn't seem to work even with all the files set to those CSR. ...
2
votes
3answers
2k views

How to extract one band from a three band raster in ArcMap?

I'm fairly new to ArcGIS and I get into trouble extracting a single band layer from a raster image .img in ArcMap that I want to use after in zonal statistics. So far, all help I found is to do the ...
1
vote
2answers
949 views

Can you change the processing extent in environment settings using python to a shapefile?

I have managed to do this manually at Geoprocessing>Environments>Processing Extent and setting the shapefile in the drop down bar. I was wonder if this could be automated with a python script? My ...
0
votes
1answer
147 views

TileMill raster-colorizer

I am trying to use the raster-colorizer in Tilemill (v0.10.1) but it is giving me an error. I did set in the advanced section the band to band="1". What else do I have to do in order to use ...
2
votes
3answers
228 views

How do I get the value of the pixel under the cursor?

Is there a tool or something that will give me the value of the pixel under the cursor? What I've got in mind in something like the eyedropper tool in graphics programs that allows you to ...
1
vote
2answers
158 views

Create line between polygon and nearest raster cell

I need to create a line between polygons (centroid) and the nearest cell of a raster dataset. The polygon and raster do not intersect. Each polygon has a UID. One cell can be linked to many polygons, ...
3
votes
2answers
44 views

Average Proximity Metric

I'm looking for a metric that gets at average distance to a given feature. For example, for a point in the water, how far, on average, is the land or to what extent is the point surrounded by land. ...
6
votes
2answers
433 views

How to force 1-bit raster output in ArcGIS 10.1 for Desktop?

Any ideas on how to force a 1bit raster output in ArcGIS 10.1? By default, ArcGIS is being very dense about recognizing pixel depth. I have a binary raster [0,1] and a mask raster [1] and they are ...
2
votes
5answers
352 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 ...
1
vote
0answers
199 views

QGIS 2.0 Problem with loading a Layer Style file that contains a transparent pixel list

I work with QGIS 2.0.1. For my raster file I have created a Layer Style with a transparent pixel list. When I import a rasterfile in a new project and load the layer-style file, the map changed to ...
1
vote
1answer
129 views

Geoserver GeoTiff Raster Layer Turns Shade Pink (Not Pink Error Tiles) [duplicate]

I have been given some geotiff files, sample of one is here I published these files as an Image Mosaic Layer in Geoserver. All is fine except that all the displayed geotifs, at all zoom levels are a ...
0
votes
0answers
85 views

Update a NetCDF file using GDAL

I have to edit a NetCDF file using GDAL in C++ code. When I try to update a subset I have this error message: ERROR 6: The NETCDF driver does not support update access to existing datasets. How can ...
1
vote
0answers
144 views

Fill tool creating large output files from sections of a Raster

(This raster information for one of the clipped rasters) I have a raster image representing a landscape that is about 1.3Gb. I clipped the raster into 31 sections which vary in size from 10Mb to ...
4
votes
2answers
475 views

Merge two rasters with no data value

I have two rasters: Raster A and B. Raster A has has only values of 0. The white area in Raster B are No Data values. I want to merge them to one raster (Raster C). So basically I want all pixels in ...
1
vote
1answer
253 views

ListRasters not recognizing raster files in python

I have 2 rasters in my workspace, one in TIFF Format and the other in GRID format: "C:\ExampleFolder" When I use the python script: import arcpy >>> ...
0
votes
1answer
433 views

Error in raster displays of NoData cells when “zoomed in” past scale 1:3,000,000

I looked around GIS stack exchange and ArcGIS Help pages and didn't find anything on this issue. I have encountered an error in how Arc displays a Raster file (.TIF format) at different scales. At ...
1
vote
1answer
257 views

How to calculate size of a pixel for a scanned map?

A land use map has a scale of 1:150000. The map is scanned at a resolution of 150 DPI. What will be the surface area in m square represented by each pixel in the resulting easter map?
3
votes
1answer
143 views

Why does Save as “Rendered Image” change the raster styling?

Rasters exported from QGIS (via Save As > Rendered Image) do not retain original styling. See attached. Any thought on how to prevent this error? The top image is exported from QGIS as a .bmp, the ...
1
vote
2answers
72 views

View an .ecw-file in QGIS 1.8.0? [duplicate]

I have got a .ecw-file that I want to somehow import into QGIS 1.8.0. Is there a plugin that I can install that can help me do this or is there another way? The .ecw-file contains rasterdata.
3
votes
4answers
2k views

Clip a raster using a shapefile into multiple rasters?

I have a raster file representing a large area and a shapefile of 30 polygons representing watersheds. I would like to clip the raster with the shapefile to create 30 rasters representing each ...
1
vote
2answers
171 views

gdal_grid has some problem with reading vrt file

I am using gdal_grid module(from gdal 1.10) and it has some problem with reading the vrt file. I checked this link but it does not work. gdal_grid problem reading vrt file The command is ...
0
votes
1answer
178 views

Topo To Raster executing but not creating the raster

I am using Topo to Raster by File (ArcGIS version 10.1) via arcpy on a large stream and point dataset. Arcpy runs fine and executes without issuing any error message, however it does not create the ...
0
votes
1answer
72 views

Attribute names being truncated during extraction

I have 30-40 raster layers and each raster has approximately 40 columns. The attribute/column names are very long, and the beginning of each column name is the same. During the extraction process, ...
1
vote
1answer
305 views

Converting a raster to a polygon

I need to convert a raster into a polygon, and I ran into "Error 000863: Invalid GP Data Type" After searching, I saw this solution online. Basically I needed to convert the float raster to an ...
0
votes
3answers
93 views

ArcGIS - ModelBuilider - Collect Values not working as expected

I am trying to iterate through a folder of rasters, reclassify each raster, then combine all of the reclassified rasters using Cell Statistics (to get the overall SUM of the reclassified rasters). I ...
2
votes
0answers
104 views

Write raster with its attribute table and symbology

I am classifying lots of rasters and I'd like to automate the legend creation and symbology displaying for easy manipulation. Here is the kind of raster I'm dealing with: library(raster) r <- ...
1
vote
2answers
343 views

How to change raster cell values within a polygon using QGIS GUI?

I would like to know how to change the values of raster cells which are within a polygon, leaving all cell values outside the polygon unchanged. I would like to subtract 1.5m from each raster cell ...
1
vote
2answers
230 views

QGIS howto create raster from map canvas easily

i have question ho to create raster from QGIS map canvas (what i seen in my qgis) easily. Now i have used print composer and after some luck i get whole dataset into map item, after that i throw lucky ...
0
votes
2answers
470 views

Batch merge large numbers of.asc grid files

I have >2.5k .asc grid files which I need to merge into a single overarching dataset. I would like to avoid having to convert them into esri grids first so was looking to use QGIS (v.2.0). I am ...
0
votes
2answers
92 views

Is it possible to alter raster values without Arcpy? [closed]

I'd like to be able to alter raster values, through fairly simple equations, without using the module Arcpy. Is that possible? It seems like gdal, numpy, and rasterlang might make this possible but ...
2
votes
3answers
961 views

How to get count of non-NA raster cells within polygon using R

I've been running into all sorts of issues using ArcGIS ZonalStats and thought R could be a great way. Saying that I'm fairly new to R, but got a coding background. The situation is that I have ...
0
votes
1answer
278 views

QGIS 2.0 Howto copy raster data from a QgsRasterDataProvider to an OpenCV matrix

I'm hacking the half day arround a problem and that I' thought it was simple one. I'm using C++ (QtCreator) QGIS 2.0 und openCV2 on an 64 bit Workstation runnig Debian Wheezy. The Application I try to ...
2
votes
0answers
224 views

How to best intersect vector data with raster data?

I have Open Street Map [OSM] data imported so that I can access the geometry of buildings. I have also loaded SRTM digital height data from NASA from a GeoTIFF raster. I have projected the raster into ...
2
votes
1answer
169 views

Analyse slope gradient from LiDAR .asc data

I'm new to using QGIS. I have purchased some LiDAR data which downloads as .asc format, is there a way to analyse the terrain slope angle from this data or does it need to be converted into DEM? ...
1
vote
3answers
187 views

How to create a multi-colored raster image based on long,latt,color information?

I want to create a multi-colored raster layer to overlay on my map in OpenLayers I have the following information in my DataBase: D_Cell_ID Long Lat ColorCode 055113 ...
4
votes
1answer
93 views

Cutting Raster using two Polygons as Masks

I am trying to cut this raster in order to drop the outside of the walls white area and the area with the dots. I made one step using as mask the green polygon but i couldn't remove the inside of the ...
1
vote
0answers
313 views

TIN to Raster Tool, output elevations are 3.40282e+038 and -3.40282e+038, tried calculate statistics didn't work

I have an input TIN file that I created using Create TIN. The elevations are all correct. When I convert the TIN to Raster using the tool, my output elevations are 3.40282e+038 and -3.40282e+038 ...