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
19 views

Convert colorized/styled vector (KML or qgis-project-origin) to raster and preserve the colorization

I can very rapidly create nice heatmaps (chloropleths actually) using qgis that I can then export as kml's that have the correct colorization when displayed on Google Earth, etc. I'm wanting to ...
0
votes
0answers
12 views

How to repeatedly mosaic raster in Erdas?

I have found script to mosaic raster in R. But the output raster size is almost 9 times bigger (92mb) than mosaic it in Erdas (12mb). So I prefer mosaic raster in Erdas. But it wastes so much time to ...
0
votes
0answers
36 views

Bi-Weekly NDVI data into monthly Datasets

I have NDVI data in both Ascii Grid format (0.250 degrees resolution) and raster format twice a month like: ndvi1981_07a ndvi1981_07b I would like to combine these bi-weekly values (average) into ...
0
votes
0answers
11 views

Oncoming intersection or intersection density

Through the use of Android and its on board GPS module, I am looking to calculate the density of intersections in a given area. Say 1 km x 1km. How would I go about accomplishing this? I am new to any ...
0
votes
0answers
21 views

How to view a raster in CartoDB?

What is the easiest way to view a raster in CartoDB? From the list of formats that you can upload into CartoDB, I noticed that .tif is available, so I've tried adding a GeoTIFF, but it says that ...
0
votes
0answers
32 views

How do I convert a .bil (and associated .clr, .blw, .hdr, and .stx) files into georeferenced rasters in R? OR to geotiffs using gdal_translate?

The title says it all. I've got a bunch of .bil files, which I can open in R using the raster command pointed to the path to the .bil file. But I don't know how to efficiently incorporate the ...
0
votes
0answers
17 views

How do you visualize change in rasters over time in CartoDB?

I have a series of satellite image rasters. I need to show the change over time of these rasters. Would the best way be to change the basemap with the click of a button for each? Has anyone got an ...
0
votes
0answers
18 views

Qgis Server, show Oracle Georaster dynamically

I have an Oracle Spatial database and I use rasters (SDO_GEORASTER). I can render some rasters on a web page with Qgis Server : when I render the maps on the webpage, it come from a qgis project ...
0
votes
0answers
14 views

gt:VectorToRaster in Openlayers

i would like to opa vector table using "gt:VectorToRaster" a WPS function in Openlayers. my vector table is stored in Postgis 2.1 and published in geoserver. i need the code to do this, can you help ...
0
votes
0answers
59 views

R plot raster with real colors

I'have a raster image from Scran25 IGN. In Qgis, it opens perfectly but in R (with rgdal or raster packages), I do not know how to keep the original colors like this exemple? I have tried ...
0
votes
0answers
36 views

rasterize table polygon postgis 2.1

I would like to rasterize a postgis 2.1 polygon table, but I don't undersand how to create the SQL function syntax for ST_AsRaster. My vector table has 3 fields: gid, recharge, and geom. The SQL ...
0
votes
0answers
23 views

GeoTIFF Mosaic/Crop/Translate: Easiest Method in QGIS?

I routinely have to mosaic multiple GeoTIFFs together, extract a rectangular area, and save that area as a JPG with a world file. Typically I've been using commercial software for that (Geographic ...
0
votes
0answers
20 views

QGIS-Merge or create virtual raster files without losing definition?

I am new to QGIS and relatively new to GIS (so please be aware I am not that familiar with a lot of technical terminology). I am trying to merge several tiff files as either a virtual raster or a ...
0
votes
0answers
38 views

How to calculate a population weighted centroid using a raster and shape file in QGIS?

I am very new to QGIS so please help me with a step by step answer. I have a raster file with population count and a shape file based on a large population and shape file. I have successfully created ...
0
votes
0answers
5 views

View information raster data in postgresql

I download and use raster2pgsql.exe import tiff image into postgresql. Can i use the query to retrieve the information of the image does not? Information such as: date of capture, capture time.
0
votes
0answers
26 views

The difference when querying raster and vector

Hi everyone I have two queries have the same meaning but different results. Why is there a difference?. Queries are true? query 1: query 2:
0
votes
0answers
25 views

Is there a Raster2pgsql GUI?

Has anyone ever attempted to create a raster2pgsql gui (like the shp2pgsql gui). As I am sometimes lazy to use command line, this could be a very nice to have.
0
votes
0answers
29 views

qgis's georeferencer renders my white map with a translucent blue tint, can I prevent this?

I'm running QGIS 2.0.1-Dufour on MacOSX and when loading a PNG or TIFF into qgis as a raster its always getting rendered with a blue tint. Here's what it looks like before being loaded into QGis's ...
0
votes
0answers
25 views

Rasterizing vector contour data: Python error message

would anyone know why qgis kicks up this error message (image attached) when using v.to.rast.attribute? the rasterise related to a contour set. i duplicated it twice to create 3 copies. the first ...
0
votes
0answers
40 views

Arcpy raster calculation producing random no data cell in output

I've been trying to get the raster calculation below to work using python: import arcpy from arcpy import env import os from arcpy.sa import * arcpy.CheckOutExtension("spatial") KSat_mm = ...
0
votes
0answers
38 views

time processing

I am computing NDVI for Landsat TM in grass 6.4.3 in raster map calculator, and time processing is many hours and finally tke message is "failed". trying to find a solution I discovered that it ...
0
votes
0answers
24 views

Disable option in QGIS which picks 4th band as alpha band

Is there a way to disable that function? As somebody who works with 4 band orthoimagery on a daily basis, it is annoying to go to the transparency options every time I load an image to disable the ...
0
votes
0answers
21 views

Slope regions from elevation points using QGIS 2.0

I am using QGIS to create a layer of slope region polygons (e.g. less than 30% slope, 30-50%, more than 50% categories). My data comes from point elevations and I interpolated using SAGA b-spline ...
0
votes
0answers
22 views

rasterize a geography polygon using postgis 2.1

I am still bit new to Postgis 2.1. I am trying to rasterize a polygon, meaning that I have a polygon of Syria and I want to create an empty raster that contains the shape and geography reference of ...
0
votes
0answers
65 views

Issues creating slope raster layer from a point layer

I'm trying to create a slope raster layer using QGIS 2.0 on Windows XP. I started with a points layer with the Z elevation attribute. I then used the interpolation plugin to create a DEM. But, ...
0
votes
0answers
15 views

extracting values from maps and inserting into a summary table

I have several maps that I am working with. I want to extract the values (1, 0 and NA) from the maps and place them all into a summary matrix. Since I have so many maps, I think its best to do this as ...
0
votes
0answers
31 views

How to draw rotated symbol RASTER type layer in Mapserver?

[PARTIALLY SOLVED]: I was on the wrong track I need to use a UVRASTER, see this part of the docs But doing leaves with with another question about how to get the angle correctly, please see this ...
0
votes
0answers
46 views

How to get RasterToPolygon working

We have a process that is almost working except for this one call ... This is the one tool function that is requiring a FeatureClass and I found code that I thought would work. Unfortunately all I ...
0
votes
0answers
26 views

R equivalent of GRASS r.grow?

What is a good R equivalent of the GRASS function r.grow? The closest I've been able to find is the script suggested by whuber in response to Creating randomly shaped clumps of cells in a raster from ...
0
votes
0answers
33 views

Assign a particular projection for un-projected raster/vector files in a folder/sub-folders

We are having 1000's of raster images/vector (shp,tab,dxf) files in a folder/sub folders. Is it possible to check the projection of those and if it is an un-projected one? WGS 1984 has to be ...
0
votes
0answers
36 views

QGIS 2.2. raster color ramp

I have just upgraded from QGIS 1.8 to QGIS 2.2 and I am missing very much 1-band raster color ramp plugin that I had easily colorized my DEMs by using pre made color brewer such as DEM screen or DEM ...
0
votes
0answers
22 views

glm with raster data: species decline~ ndvitrend

I have species decline data (number of population per year, over a period of 23 years) out of ndvi data for these 23 years I calculated the trend, and mapped it. now i'd like to relate the negative ...
0
votes
0answers
37 views

Why does merge/mosaic four DEMs into one give ERROR 01042?

I'm unable to merge 4 dems into one using ArcGIS Home 10.2. Raster Calculator, adding them, gives me the error: RuntimeError: ERROR 010422: Error in processing the environment mask. I created a ...
0
votes
0answers
22 views

Is the “1-band raster colour table” plugin available in QGis 2.0?

I used to use the "1-band raster colour table". Is it still available in QGIS 2.2.0? It seems like I can't install it (I don't find it in the list of plugins available, even after installing the BC ...
0
votes
0answers
33 views

How to crop an image into more than 80 small sections automatically in R

I'd like to crop an image into 15 sections in R. The image projection is Geog lat/long, extending 87 to 120 degree in East and 45 to 55 degree in North. I want to separate it by every 2 degree. So I ...
0
votes
0answers
55 views

Opening netcdf in arcmap as a raster with uneven coordinate spacing?

I have SMOS CATDS 2010-2013 daily data that is in EASE-grid netcdf format. I have 100 sites that I need specific daily soil moisture values for from this dataset. I have daily AAFC CATDS soil ...
0
votes
0answers
22 views

Display one of many rasters in Web Map

I would like to interactively add a georeferenced tif to my webmap. Use case is: I have a raster catalog of georeferenced tax maps. I would like to be able to select those tax maps (there are ...
0
votes
0answers
27 views

Regression analysis - creating dataset

I have a vector-based dataset of soils/parent material. The statistics have already been done, with coefficients for each category of parent material. I am not sure how to use this information to ...
0
votes
0answers
30 views

Raster projection problems

How would I go about specifying the following projection in Arc and QGIS? After defining this, how would I then go about changing the spatial reference to ESPG 27700? The following are the details of ...
0
votes
0answers
26 views

Calculating raster values from center to edges to represent normal distribution

Edit for simplification/clarification: What I want to do is take a raster and calculate cell values from center to edges such that the center has an arbitrarily determined high value which decreases ...
0
votes
0answers
39 views

Error: .asc is not a supported raster data source

I am new using QGIS and struggling with this error "...... .asc is not a supported raster data source" when trying to add a ."asc" file as a raster. I downloaded the files from ...
0
votes
0answers
82 views

Unserialize socklist error when using rasterEngine in r

Basically, I am running the "rasterEngine" function in R. I want to use parallelization to change values in a raster image (I have around 400 images that I need to work on). However, the rasterEngine ...
0
votes
0answers
54 views

How to open a raw binary raster in QGIS or R

I have a raw binary raster without a file ending, and no header file. I would like to open this in either QGIS or R and then convert to geotiff, but opening it seems to be a challenge. Here is a ...
0
votes
0answers
54 views

Is it possible to apply affine transformation (translation) to raster image?

Is it possible to move/translate a raster image in QGIS 2.2 (without using georeferencer) just like it can be done with a shapefile ? If not, alternatively can this be done with ArcGis?
0
votes
0answers
63 views

Make a raster with pixel scale 100 by 100 meter with gdal_rasterize

I'm asking here, because, I've got great results last time. Here it is the next of my adventure with gdal_rasterize, I want to make a raster picture where each pixel correspond to a square of 100 by ...
0
votes
0answers
28 views

How to accurately join data based on 1x1 degree grid-cell points to a shapefile

In the data file each row represents a country and a grid-cell at 1x1 degree resolution, and the given coordinates, in longitude and latitude, label the south-west corner of the grid-cell. The ...
0
votes
0answers
16 views

Edit a classified grid file (.grc) to improve accuracy

I have a .grc file (classified grid file) which contains some clutter information, forest, sea, woodland, etc... I need to alter the data in some area to improve accuracy. Basically a larger forest or ...
0
votes
0answers
43 views

How to set raster values to NULL?

how can I define values to null? I tried it with the processing reclassify tool but I always get an error log (cannot open the result shape...or something like that).
0
votes
0answers
30 views

How to raster vector- and shape-files correctly

does anybody know how to convert vector- and shape-files correctly? Doesn't work with tab Raster/convert/vector to shape files. The output always contains strange input-data (wrong and strange ...
0
votes
0answers
34 views

Error building pyramids/statistics on raster with arcpy

I am building a script to process rasters with the option of adding the extra step of building pyramids and statistics at the end. For some reason, it will not recognize inputs as legitimate raster ...