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
2answers
48 views

Creating a raster file from a shapefile using GeoTools with different colours for different features

The shapefiles that I am processing display information on an operation of a piece of equipment over an area, where the information is stored in steps as polygon features with various attributes and ...
0
votes
0answers
19 views

Loading rasters using agent analyst

I'm new to agent-based modelling, but have been using GIS for a number of years now. I am trying to create a simple model that shows the potential loss of salmon from a number of locations due to ...
2
votes
2answers
97 views

Selecting Polygons that have certain raster data within them

I am using a raster layer with either 1 or 0 in each cell. On top of this layer, I have a European countries shape file. The countries that contain a '1 cell' in the raster beneath are the Countries I ...
0
votes
0answers
75 views

Improve Slope Raster Precision?

Im working with ArcGIS and i have a raster layer created with just four points in XYZ, the plane that forms between these four points has a slope of 10 percent. When using the tool SLOPE (3D Analyst> ...
1
vote
0answers
15 views

QGIS world files rather than .xml [duplicate]

Is there a way to get QGIS to write out a world file (.wld/.pgw/.jpw) etc rather than an aux.xml. I see the aux.xml is in general better but it isn't supported by the other software I am using. I can ...
4
votes
3answers
81 views

Points to raster - interpolation

I have a point layer with soil values. How can I get a raster layer with different classes of values, since there are areas without point sampling, what´s the best way to have a regular cover of the ...
-1
votes
1answer
29 views

Converting UTM55 to WGS84 in ArcMap? [closed]

I've got a raster in UTM55 over Australia and I would like to convert it to WGS84. Any idea how to do it ? The problem starts when ArcMap recognize it as 'Geo-Reference' only and not as UTM55, so I ...
1
vote
1answer
37 views

How large is the entire ASTER Global DEM on disk?

I see from various online sources (including GIS.SE's own How to download the entire ASTER GDEMv2 dataset?) that the ASTER GDEM has 22'000 tiles, each 1°×1° and 3601×3601 pixels (each pixel being ...
1
vote
0answers
35 views

Handling warning about DX and DY in gdal_translate from .Gtiff to .ASC?

When I try to convert Gtiff to .asc file, QGIS shows the warning: Producing Golden Surfer style file with DX and DY instead of CELL SIZE since the input pixels are non-square. Use the FORCE CELL SIZE ...
2
votes
1answer
51 views

Displaying RGB raster on QGIS with no enhancement with Python Console?

I'm working with a RGB raster on QGIS 2.6.1, on a Windows 7 machine. I need to set the Contrast Enhancement option to No Enhancement with the Python Console (not through the Layer Properties ...
2
votes
2answers
85 views

How to calculate the distance to the nearest water source?

I have a polygon hydro layer of my study area and am trying to calculate the distance to nearest water bodies from my site. Since my site are 2km*2km grids I am not sure how to calculate it? Whether ...
1
vote
1answer
53 views

Problem with importing GeoTif files in QGIS

I have installed the new version of QGIS (2.12) and the newest OSX version (El Capitan). When I tried to open GeoTif files with QGIS, it always crashed! Then I tried an older version of QGIS (2.8) and ...
1
vote
1answer
34 views

Using OR and ISNULL in Raster Calculator

I am using ModelBuilder for ArcGIS Desktop 10.2 I have the following code in the Raster Calcualtor which works in some cases but not in others. Int(Con(IsNull("%A%")|"%A%"== 0,"%B%",float(%Max%) + ...
1
vote
0answers
39 views

Raster to ascii tool converting all data to one value (ArcMap)

I am having an issue when converting a raster to ascii. With extract by mask I have selected the area I am interested in and subsequently resampled the data from 5km to 2 by 2 m (required for use in ...
0
votes
0answers
19 views

USGS Raster Conversion with GDAL Returns Blank .TIF File

I am new to GIS systems. I installed GDAL to convert .ADF files to .TIF files to obtain image heightmaps. It outputs a GeoTIFF .TFW file that I can't open, and a .TIF file that is blank (all white). ...
0
votes
0answers
30 views

Preserving Reclassified Values as Attributes?

What is the BEST way to preserve original raster values as attributes in the output raster when reclassifying? I see that this question has been asked before as Making reclassified raster layers ...
1
vote
0answers
26 views

Attribute table not changing when using Mosaic on rasters

I'm looking to "merge" 2 rasters together. One is the original base land cover raster with 6 classifications/land use classes. The other is a raster from converted polygons that are essentially ...
1
vote
0answers
25 views

Can't set transparency to a RBG raster on QGIS

I need to display an RGB raster on QGIS, with Multiband Color render type. After I set the Contrast Enhancement option to No enhancement, this is how the image is displayed. No issues so far, since ...
1
vote
2answers
46 views

Changing height/interpolation/shape of raster layer

I am kind of a beignner in ArcGIS and thought about and googled this problem for two days now. I am working in ArcScene making a 3D visualization of a bedrock surface of a town. I have a polygon ...
0
votes
1answer
48 views

Creating point shapefile from GeoTIFF using GDAL/OGR?

I have a 0.05 deg global maps (~8000 files) in GeoTiff format. It's a kind of a mask containig "1" and "0". I need to create a point shapefile for each raster with points located over "1" values of ...
0
votes
0answers
13 views

need to clip multiple USGS quadrangles in Geotiff format to statewide index in polygon format

I need to trim the collars off of many USGS 7.5 minute quadrangles for a state. I have the quads as GeoTiffs and have the polygon boundary for the whole state. I think there are about 1446 ...
0
votes
1answer
33 views

Raster copy multiple rasters keeping name but dropping extension

I have ~100 rasters I need to clip to an area. All rasters are saved as .bil files, and for use in later processing I was trying to make these have 'no extension for esri grid', but keep the same ...
1
vote
1answer
55 views

Raster data QGIS and SpatiaLite?

I am a german student and study Geoinformatik. I have the task to store Raster data in SQLite. So use the turotial from the gaia page to Create a database and store a image (TIFF) named NaturalEarth. ...
1
vote
0answers
29 views

I clip a raster with a vector mask in qgis, the result is correct but its a little bit of, why is this?

On one side the result is "bleeding" over the vector on the other side its more than one raster pixel from the vector on the inside. How to correct this? http://i.imgur.com/d0v6mqt.png ...
0
votes
0answers
16 views

Display PostGIS raster as GeoTIFF layer in QGIS [duplicate]

I want to display a raster loaded into a PostGIS (2.2) enabled PostGRES database (9.3) as a GeoTIFF layer in QGIS. I get the sense that this needs to be done by creating a view in PostGRES and then ...
1
vote
1answer
45 views

QGIS slope percent calculation

I'm using QGIS and I'm trying to calculate slope < 20% from a file I have but when I use the raster calculation SLOPE < 20 the result is all black. What am I doing wrong? The data is already in ...
0
votes
0answers
31 views

How to test if a point shapefile is in a raster in ArcMap using Python?

I have a shapefile where the features are points. It should be about 500 points. All of this points are on top 5 different rasters. Some points are in one raster, but some others are not. I need to ...
3
votes
2answers
141 views

R raster predict using lm() time series

I try to make a prediction in raster using linear regression based on past rasters but I can not capture the lm() model in order to feed it to predict(). # # calculate regression in a raster stack ...
0
votes
1answer
25 views

Performing spatial join on two rasters using ArcGIS for Desktop?

Have search on this question but cant quite find the solution i seeking. I have two rasters, one with nodata cells the other is complete. I am seeking to combine the two rasters. Where there is a ...
0
votes
0answers
21 views

Spatial Join Points Vector with Raster Dataset using Arcmap

I have a points file of taxi drop off locations and a raster file grid. I am trying to get a count of each point on a raster cell. How do I go about doing that? It is like I am doing a spatial ...
1
vote
1answer
41 views

PostGIS Raster performances

I ingested two Landsat images into PostGIS database using : raster2pgsql -I -C -s 28356 -M -t 100x100 LS7_20150425_B40.tif public.red | psql -d postgres -U postgres raster2pgsql -I -C -s 28356 -M -t ...
1
vote
0answers
24 views

Best way to store, elaborate and query raster data [closed]

I have created multiple raster images with GRASS-GIS (~150Gb), that I'll need to multiply for a certain coefficient, and query the results that need to by saved just temporally. The portions of the ...
0
votes
0answers
32 views

Strange display of raster in ArcMap

I have a Raster file jp2, in the full zoom there is a strange black dots on the border of the raster, but keep zooming these dots disperses see images
3
votes
1answer
54 views

What is faster - a matrix, raster or a dataframe?

I have rasters over which I am performing mathematical operations. For example, where I need to calculate flow distance or distance between two grid points. What format is generally considered faster ...
1
vote
0answers
9 views

Adding .tif files with various bit depths to a raster mosaic

So I have a few georeferenced .tif files that I need to add to a raster mosaic, however the problem is that some of these are 8 bit unsigned TIFFs while others are 1 bit unsigned. After adding all ...
1
vote
1answer
51 views

Using raster2pgsql to display data in QGIS

I am quite new to this process (using raster data in PostGIS) and tried to find some tips/solutions on other threads but I didn't manage to get things working. I ingested some Landsat data into my ...
4
votes
3answers
103 views

Irregular XYZ point data to raster (TIF) - LASTools alternative?

I am trying to convert my irregular spaced point data (xyz) to a DEM and then, to a raster (geotiff). Because of the irregular spacing I need a triangulation first, right (so, no spaces are in the ...
1
vote
0answers
41 views

G_Malloc error for Grass module(r.stream.extract) in R

I am having a big issue of this G_malloc Error while using a module of Grass (6.4.4) (r.stream.extract) in R. Initially I thought my computers configuration was low, So I switched to 8gb Ram 64-bit ...
1
vote
1answer
44 views

No Data in raster while Mosaic using ArcGIS

i have several tif files, which some of them have No data values. when Mosaic these files the ArcGIS replace the NoData value with black color RGB(0,0,0). I want to keep the No data value in the ...
0
votes
0answers
22 views

DEM Mosaic Dataset Processing - Output Surface and Hillshade raster to same extent as input raster tiles

I have a lot of DEM rasters, tiled adjacent to each other. I would like to make a surface and a hillshade raster to the same extent as each DEM tile. Current issue: processing on a tile-by-tile basis ...
0
votes
1answer
76 views

Best resampling method for DEM?

I have a task to slice 10m elevation model into the 0.1 x 0.1 degree tiles. I also have to change the projection method used in the TIFF - the WGS84 (Mercator) is a must. I have implemented the ...
1
vote
1answer
34 views

Assigning a value to a polygon cell

In ArcMap 10.3 I have a raster file with a polygon grid overlayed on it: If the pixels in the colored raster have values such as blue = 5, yellow = 1, green = 3 etc, is there a way to output a table ...
0
votes
0answers
35 views

Convert raster to polygon then join attributes

I'm trying to convert IMG files to shapefiles, then joining the attributes of the IMG file to the new shapefile. I got the conversion part to work, but am a stuck on how to join the tables. I have ...
0
votes
1answer
76 views

Reading netcdf sub variables and convert to raster grid in r

I want the open the fs variable which in under Retrival category and covert that into raster grid. library(ncdf4) file <- ...
0
votes
1answer
35 views

Merge several .lyr files that contain a raster photo column

Shapefiles do not support raster files, so I created a geodatabase and made feature classes of the points. I then added a column titled "photos" and added the photo as a raster to the point. I now ...
2
votes
0answers
48 views

Create a raster dataset containing the number of returns from a las file? [duplicate]

I already created DEMs, DTMs, DSMs from a LiDAR (LAS) file with a little help from the internet. However, right now I'm kind of stuck in my research. I want to create a raster file which contains ...
1
vote
1answer
39 views

How to interpolate only cells in a raster that are adjacent to existing cells with a value

I have raster data of a continuous field. I need to calculate zonal statistics on that data for some polygons (e.g polygons A and B in the image). It is essential that I have as complete as complete ...
0
votes
1answer
47 views

Create a World File from bounding box

What is the most pythonic way to create a Word File for a .png image, having only it's bounding box? For example, given the following bounding box: <LatLonBox> ...
1
vote
0answers
36 views

Calculating flow distance of pixel from outlet using R?

I have created these raster files for a river basin: DEM Flow Direction Flow Accumulation Also, I have another raster with values of rainfall. All the 4 rasters have same spatial extent, ...
1
vote
1answer
55 views

How to add time and elevation dimension attributes to Geoserver rasters?

In geoserver, when I edit a postgis raster layer and click on the Dimensions Tab, I can't enable either of the Time or Elevation dimensions. The following message appears next to each of the ...