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

learn more… | top users | synonyms (1)

0
votes
0answers
13 views

Exporting QGIS Raster/Vector layers into one PDF? [duplicate]

I have seen a similiar post to this a while back (Is it possible to export GeoPDF from QGIS?), and thought I would try asking it again to see if there has been any improvement or new knowledge on ...
0
votes
1answer
24 views

Creating Dem from cross sections

I have a question I appreciate that if someone can help me I have a DEM in arcmap and cross section of a river which flows on the Dem in Hecras. I now the cross sections are more accurate. I want to ...
1
vote
0answers
10 views

Retrieve list of all features and values from raster layer (Geoserver and Openlayers)

I'm trying to retrieve a list of all values from a raster layer (GeoTIFF) in geoserver (2.5.x). I tried to modify the code from http://trac.osgeo.org/openlayers/wiki/GetFeatureInfo but I can't seem ...
2
votes
1answer
17 views

Harvesting pixels using GRASS GIS

having a binary raster map of pixels of interest, a road network, and a target point, my goal is to get a raster map with network pixels having as value the number of pixels of interest they allow to ...
0
votes
0answers
15 views

WPS: how to write output to a raster layer in GeoServer

In GeoServer vector-based Web Processing Service (e.g. gs:Import), we can have the output saved to a GeoServer Layer, as described in the documentation. Outputs Name Description Type ...
2
votes
1answer
26 views

How to convert different lidar data formats to raster DTM and measure its geographic position accuracy?

I'm trying to generate a DTM from lidar data and I'm new in the this field. I have different kind of files which describe the same area (different versions): *.dtm *.xyz *.xyz with variable grid ...
5
votes
1answer
53 views

How can I match the cells of two rasters?

I have many raster files each one containing information that is different from the others (e.g. one contains information on rain, the other on altitude, and another on land use). The cells in each ...
0
votes
1answer
26 views

scatterplot of two rasters in R

I am very very new in programming and I want to ask how can I make a scatterplot of two rasters in R and also get their correlation of determination?
0
votes
0answers
33 views

Creating spatial Reference to ASCII file

I have produced ASCII files in MaxEnt. These files are able to be loaded into Arcmap10.1 and display as an image, but i cannot interpret them or create them into a polygon for further analysis. I have ...
3
votes
0answers
33 views

Postgis database query optimisation

I have a set of rasters in DTED format which I load into postgis database using raster2pgsql command line tool. Each of rasters is simply stored in a row and described by rid and a value of raster ...
1
vote
1answer
11 views

regression model with randomForest in raster package

I'm learning randomForest classification method in R and I performed land-use classification with randomForest and raster packages. But when I try uesd a regression model produced with randomForest to ...
2
votes
1answer
36 views

Opening GeoTIFF (georeferenced in ArcGIS for Desktop) in QGIS?

I tried to open a georeferenced geotiff created in ArcGIS for Desktop in QGIS. I could open them but they are not in the right spots. These raster datasets contains .aux .rrd .tfwx .tif.aux.xml ...
0
votes
0answers
18 views

Update Raster extent

How do you update raster's extent after you export the raster ? I forgot to enable the Date Frame rather than it's original Dataset ? Thanks.
4
votes
2answers
45 views

Visualization of a field in Leaflet

In a Leaflet app I want to overlay raster data (technically speaking, a field) on a web map. The data consists of triples < lat,lon,value >, where value is in range [0,1], for example: ...
0
votes
0answers
11 views

PostGIS raster write support in R

I want to push/write some generated raster layers to my postgres database directly in R. In theory this could be supported by the rgdal package, but sadly it isn't. In the latest version only copy, ...
2
votes
2answers
48 views

Arcpy Slope Analysis Script

I'm trying to run slope analysis in ArcGIS. I have written an ArcPy script that converted feature layers to raster files. Now I have a list of rasters (each with a unique name) in the table of ...
3
votes
2answers
42 views

OpenWind Zone of Visual Impact transparent pixels?

How do you make pixels which are not visible from a point be made transparent and the pixels which are visible opaque so that I can overlay the raster over a map to see clearly where you can and ...
2
votes
0answers
24 views

geoserver and openlayers select rectangle pixel values

I'm running a geoserver (2.5.x) with 1 raster file (GeoTIFF) as a layer. From my application I can access a single pixel value when clicked (through WMS), but what I'm really interested in is to get a ...
3
votes
2answers
21 views

QGIS ASCII Grid output problem

I have this .asc file of maximum temperature of a local place. This file is a result of vector to raster (GeoTIFF) conversion then GeoTIFF to ASCII grid conversion, both using QGIS. Here is a snippet ...
1
vote
2answers
27 views

Overlaying Raster image with Google Maps in OpenLayers3

I am trying to overlay Google Maps with a raster image layer in Openlayers3 and am new to this. Can anyone help by providing the steps involved in performing this task?
2
votes
1answer
33 views

Subset multiband tiff file using Python in ArcGIS for Desktop?

I have a multiband (1140) raster file in tiff format that I want to subset. Each band represents a prediction of monthly rainfall (12 bands for each year) over a 95 year period (12*95=1140). I need to ...
2
votes
1answer
32 views

What are the PostGIS Raster Constraints used for?

My question is quite basic, but I have not found a simple explanation of why raster constraints are useful. I have worked with rasters in PostGIS for a while but only recently I realized that I do ...
2
votes
1answer
24 views

Looking for smallish raster of global elevation data

I'm trying to find elevation data for the whole globe for a simple mapping application and I'm not having any luck. I really don't want anything fancy, just something like a 4000x2000 raster of ...
3
votes
1answer
23 views

raster statistics by line shape (vector)

I have a georeferenced area where I created 7 raster maps (classified with suitability values from 1 to 5) as I have 7 factors to check e.g. natural reserves, floods, slopes etc. From there I did a ...
0
votes
1answer
30 views

How to load postgis raster layers into R?

It is easy to get Vectorlayers into R from a PostgreSQL+PostGIS solution. library(rgdal) dsn="PG:dbname=plots host=localhost user=test password=test" plots = readOGR(dsn,"Plots") But how to do the ...
1
vote
0answers
25 views

How to get transparent nodata values in GeoExplorer?

I have a single-band raster image with NoData values set to 0. Is it possible to get them transparent in GeoExplorer?
1
vote
1answer
35 views

Loading raster in postgis and link it with an existing table

Relatively new to PostGIS and I am currently exploring the options to make one of my PostgreSQL Tables spatial. Essentially I want to store a raster object in a table that also contains essential ...
3
votes
1answer
65 views

make a raster from dataset (csv)

I was trying to make a raster from an dataset (https://www.dropbox.com/s/jsm1x06lnzfbqty/data.csv?dl=0) code: inter1= read.table("c:/data.csv", header=TRUE) #convert to spatial points ...
3
votes
1answer
30 views

Fast editing in raster calculator — adding lots of images together

I need to add pictures together to make one raster. In one session there are about 150 - 200 images (named randomly - see syntax example) There are about 50 sessions (named randomly) Is there any ...
1
vote
0answers
6 views

What should be used for website building for displaying raster data? [duplicate]

I am trying to learn website development and want to display raster data on the website which i will build, i want to know how to begin with website development and what libraries should be used for ...
3
votes
1answer
51 views

how to delete a row in grid attribute table of a raster?

How can I delete a row in a raster file table? The raster format is GRID I get this error "grid attribute table is blocked from deletion". It seems absurd that I am not able to manipulate my own ...
1
vote
0answers
31 views

How to assign lat/lon points to raster?

I'm trying to work in PostGIS with the tri.txt raster found on this website: http://diegopuga.org/data/rugged/that The raster has no SRID specified, but I know it's made up of 30 arc-second cells ...
3
votes
0answers
17 views

Distortion in projected raster

I am having a frustrating problem with something that I think should be very simple. I have a number of DEMs from the National Elevation Dataset (NED), that come standard in the NAD83 coordinate ...
2
votes
2answers
43 views

How to remove the no data area (sea) from a raster in arcmap?

I have some difficulties removing the no data part from a Geotif SRTM . I need to remove all sea part. Im new in arcgis and, help is appreciated. Thanks There you go Sir This is the result i ...
2
votes
1answer
61 views

Georeferencing a raster using GDAL and Python

I want to georeference a raster using python and GDAL. My current approach is to call gdal_translate and gdalwarp using os.system and an ugly list of ground control points. I'd really like a way to do ...
1
vote
1answer
27 views

Create Reduced Resolution Dataset (.rrd) file with modern software

I need to create, very specifically, a set of reduced resolution dataset (.rrd) pyramid files for a large set of TIFF imagery. I'm using ArcGIS 10.2, and have access to Global Mapper and QGIS. ArcGIS ...
2
votes
0answers
16 views

ArcMap - Adding Multiple raster datasets to mosaic dataset (for temporal change)

I have a number of raster datasets containing lake water temperature data. I am looking to make these time enabled as to be able to scroll through them. I have converted them to .TIFF format and have ...
3
votes
2answers
59 views

Reprojection of shapefile in R and final extraction of values

I need to extract values from some raster files (stack) using a shape file. to bring both of them in the same CRS, I first transformed the shapefile using the EPSG codes. Opening it in an GIS software ...
2
votes
2answers
52 views

Reclassify rasters using GDAL and Python

Using @SS_Rebelious very useful answer, I am trying to reclassify rasters using GDAL and Python. I have a grayscale raster (with values ranging from 0 to 255) and I want to reclassify it to a binary ...
4
votes
3answers
55 views

Converting raster file from float to integer type in ArcGIS for Desktop?

I have a float type raster file (an NDVI made from ERDAS IMAGINE) and would like to convert it to an interger type raster file in order to use Focal Statistics function (Majority). Is there any way to ...
1
vote
1answer
40 views

Extracting data, not colors, from geotiffs in R

I'm an experienced R user new to GIS, but finding my way. I've recently run into an issue that I haven't been able to find any satisfactory documentation on (but could just be searching poorly). I'm ...
2
votes
1answer
26 views

basic understanding of ArcGIS for Flex not clear on the concept

I am a complete newbie to GIS so please excuse the simple question. I am looking for someone to point me in the right direction to get some answers and/or maybe provide links to where I can find some ...
2
votes
0answers
27 views

What are my options to handle Raster Clipper ERROR 6: ADRG driver doesn't support 4 bands?

I have a tif file which contains 4 bands (RGB + alpha). The clipper does not work and gave me the message below; ERROR 6: ADRG driver doesn't support 4 bands. Must be 3 (rgb) bands. Any patch file ...
1
vote
1answer
18 views

Select value of zero from a raster and assign new value based on the majority of its neighborhood

I have a raster layer has values +1, -1, and zero. Now I want to select those pixels whose value is zero and assign them new values based on the majority of its neighbor 5*5 cells. Is there anyway ...
1
vote
0answers
23 views

QGIS 2.4 Clip function in Raster layer Style Single band pseudocolour not working?

I've been using QGIS for a while and recently upgraded to 2.4, but now find that displaying raster layers is difficult. In particular, the clip function (tick box bottom left of "Style">"Singleband ...
3
votes
1answer
37 views

Export Raster Attribute Table using Open Source software

I've got 120 or so geotiff files that I'd like to build and export the raster attribute table to something a little more friendly (e.g. csv). I'm curious if there is an open source way to do this. ...
3
votes
1answer
43 views

Zonal Statistics Tool on raster

I am working on a one-band raster with pixel values from 1 to 7, each representing a land-use class. I also have a grid of polygons and what I need is to obtain the percentage of each class in each ...
2
votes
1answer
29 views

r.recode rules file issue

I have a raster that I want to reclassify and I'm using GRASS r.recode from within QGIS v.2.4.0. The rules file I am using has this content: 0:149:1 150:229:2 230:379:3 380:459:4 460:*:5 The raster ...
2
votes
1answer
26 views

Least cost path with one-off cost for highest elevation

I'm trying to write a script to calculate the least cost path between two cells on a raster. I'm reasonably familiar with the approaches used by tools such as GRASS GIS's r.cost and ArcGIS's ...
3
votes
1answer
60 views

How are raster pixels determined whether they are in or out of a zone?

I just needed to confirm something that I think I already know the answer to because help pages are always unclear. I am running ArcGIS 10.2.2 and often use the Zonal Statistics and Tabulate Area ...