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

learn more… | top users | synonyms

7
votes
1answer
381 views

How to store Large Raster Images of Equipotential Surface Generation Using Monte Carlo Simulation?

I have a large (1GB+) raster that I am using as the base for the generation of an equipotential surface. This is to assess the accuracy of DEMs derived from another source. In situ observation is ...
6
votes
1answer
165 views

Automate Exporting of Rasters Using Renderer in ArcGIS

It is possible to export rasters in ArcMap by right clicking the layer-> Data-> Export: You can then click 'Use Renderer' check box to ensure the image you export uses the current symbology/...
5
votes
1answer
162 views

Optimizing Python GDAL ReadAsArray

I am using the GDAL ReadAsArray method to work with raster data using numpy (specifically reclassification). As my rasters are large, I process the arrays in blocks, iterating though each block and ...
5
votes
1answer
999 views

How to force RGB in a raster in QGIS?

I have rasters in 1 band 64bits float that represent real data values and for which I can set min and max using the stretch to min and max option in QGIS. I would like to convert these rasters to RGB ...
4
votes
1answer
40 views

Grid size of a Digital Elevation Model developed from topographic surveyed elevation contour line?

I have generated a Digital Elevation Model from elevation contour line. I got these elevation contour line at 20 cm interval from DGPS survey. What would be the grid size of generated DEM in "m". ...
4
votes
1answer
22 views

Conditional Combine Rasters and Track which Raster pixel used

I have 6 rasters with pixel values ranging from 0 to 1. I want to extract the highest pixel values from each raster to create a new raster, but also have a way to show which raster the highest value ...
4
votes
1answer
52 views

Is it possible to locate a specific marker point on a raster using python and use that location for georeferencing

I have several scans of the same map, which I would like to georeference. I can not use arcpy.WarpFromFile_management(...) as the rasters are slightly different due to scanning. Is there a ...
4
votes
1answer
119 views

Does gdal_calc only support 26 input raster files at a time?

In gdal_calc.py, input files are specified with letters A-Z. Here are two files, input.tif and input2.tif, being averaged into result.tif: gdal_calc.py -A input.tif -B input2.tif --outfile=result....
4
votes
1answer
181 views

Iterate through rasters in subfolders using Model Builder

I have a directory folder of precipitation data; within this folder are subfolders for years 1901-2014. In each of these subfolders are 12 .asc grid files; each file represents a month of the year (i....
4
votes
1answer
517 views

ArcGIS model builder: How to reclassify 16,000+ rasters and do weighted sums on these rasters per year?

I've been trying to build a model in model builder (ArcGIS 10.1) which can do the following task: I have a folder full of ca. 16,000 raster files (.asc) representing mean temperatures for each day ...
3
votes
1answer
32 views

Splitting, disaggregating, breaking up a merged raster file

I am using ArcMap 10.4.1 but I am also more than familiar with QGIS. I have a raster file (single band) from a merged grid on population statistics for Europe (please see image attached). The red ...
3
votes
1answer
33 views

Configuring Project CRS to reflect degree coordinates

seems like this is a common problem, but posts with similiar questions did not solve my problem. I have close to zero GIS background so apologies for my ignorance. My goal is to extract only a ...
3
votes
1answer
47 views

QGIS Has Rendering Error on JP2000 Raster. Works in ArcGIS

I've got a large .jp2 raster file that was created using 'Mosaic to New Raster' in ArcGIS. I'm trying to open it in QGIS 2.8.6 (I've tried 2.8.14 as well) and am getting a vertical line that won't ...
3
votes
1answer
76 views

Build a table with columns of raster values from multiple raster datasets, using Python, GDAL, or PyQGIS?

I have a series of raster datasets, clipped to the same extent, with matching cell resolutions, each of which represent land surface temperatures (LST) captured by the MODIS sensor. Each raster ...
3
votes
1answer
37 views

Displaying Raster Source Information

I have a large number of raster files I'm working on. I need to figure out how each of the files was processed from. I have a composite land cover map and would like to view the file names and ...
3
votes
1answer
88 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 ...
3
votes
1answer
47 views

Help with Rastercalculator - Filter areas with a certain height difference

I'm struggeling a little bit with the rastercalculator tool of QGIS. At the moment I am working with a DSM and a DTM. My aim is to filter all wind turbines out of the DSM and replace it with the ...
3
votes
1answer
318 views

Split raster into tiles

I have a raster that needs to be split into tiles (each tile a new raster). I have a Shape file with multiple polygons (these polygons are how I want the raster split). I have Gdal and QGIS. Any ...
0
votes
0answers
431 views

How to convert Raster to points in MapInfo?

I wanted to convert Raster data to point data in MapInfo.Does there any tool to convert? can anyone help me?
0
votes
0answers
87 views

Interpolation Technique

We have following solar metro logy parameter through satellite data with resolution of 100 Km^2 (10Kmx10Km) Insolation on horizontal surface Diffuse radiation on horizontal surface ...
0
votes
0answers
263 views

Problem with merging 15 DEM files in ArcGIS

I have 15 DEM files downloaded from USGS website. The pixel depth of each file is 32 bit floating, generic with format FLT. I'm then using data Management Tools > Raster dataset > Mosaics to new ...
0
votes
0answers
718 views

Tabulate area - Spatial Analyse

I am trying to calculate the amount (sqm) of land cover types (forest, water ect.) in 1045 buffer zones, all the same size (500m in diameter).. The buffer zones are polygons and the land cover is a ...
0
votes
0answers
910 views

Trying to build pyramids for large raster

I finally was able to make a slope with a rather large 5m DEM. But now I it usually wont finish drawing. When ArcMap asks to 'build pyramids' it always freezes sometimes instantly after accepting ...
0
votes
0answers
199 views

QGIS 2.0 cannot open TIFF

I've just installed QGIS 2.0 on my Windows 7 computer. I'm trying to open a raster and the system reports this message: Cannot open TIFF file due to missing codec. How can I solve it? Thanks in ...
0
votes
0answers
364 views

How to create a raster dataset from a known decimal extent?

I have an input raster pInputRaster. I want to create a new raster dataset called pOutputRasterDS that is the same width, height and cellsize as my input raster dataset (I'm not worried about ...
0
votes
0answers
49 views

How to select raster layers for averaging based on values in another layer?

I wonder if anyone have some ideas about how to solve this geoprocessing situation: 1: I have a raster layer called mixlyr_apr (representing depth values) 2: I have a series of raster layers called: ...
0
votes
0answers
99 views

Vector/Raster Intersection - Speedup and replacement for ST_Centroid

I have some raster data which is the altitude above sea level and also some vector data which represents building outlines. What I want to do is grab some buildings outlines and fetch all the raster ...
0
votes
0answers
304 views

Assign spatial reference for 1000 different ECW raster datasets using 1000 different *.prj files through python programming or .net

I am having 2000 ECW raster datasets without spatial reference and also I have 2000 *.prj files in another folder. I know only the way as right click on raster datasets-->properties-->Spatial ...
0
votes
0answers
68 views

How to deal with the situation when two rasters stacked together in arcgis?

I am doing a project about petroleum geology. There are several formations needed to add attributes (e.g. name, thickness and age). I have the raster data of thickness, so I created a raster catalog ...
0
votes
0answers
131 views

Copy Raster Tool and 1bit to 8bit

I have a bunch of 1 bit rasters (700+) of scanned maps that I need to convert to 8-bit rasters. It's the only way Geosoft will recognize the spatial coordinates of the TIF as they don't deal in 1bit ...
0
votes
0answers
88 views

QGIS: “No data” raster value for missing rows conflicts with data?

I’m having a problem with specifying “no data” in a raster dataset in QGIS 1.8.0-Lisboa. QGIS does fine in interpreting pixels I don’t have rows for as “no data” if I set Layer Properties -> ...
0
votes
0answers
109 views

Why does a shapfile shift after transformation?

I have a shapefile created in the raster package (ER_14.3_2000_poly). > #read in a raster file > ER_14.3_2000<-raster('E:/Ecoregions Models/Outputs/ER_14.3/ER_14.3_ConsensusMap3.asc') > ...
0
votes
0answers
618 views

How to fill in the parameters for kernel density estimation?

I am desperately trying to calculate animals home range with kernel. Unfortunately, the result is obviously incorrect and I cannot identify my mistake (I would like to post a screenshot but its not ...
0
votes
0answers
77 views

ArcGIS API for Silverlight: Retrieve all Data From a Raster layer?

Is it possible to use ArcGIS api for silverlight to get the data in each cell of a raster layer and store them in an array?
0
votes
0answers
107 views

Copy Raster Catalog from .mdb to .gdb, but only within a certain extent with arcpy?

I am stumped again, this website has really helped me before so here is another shot. I am trying to copy a raster catalog from a personal geodatabase to a newly created file geodatabase but only ...
0
votes
0answers
450 views

How can I calculate raster cell area for upslope contributing area

I am new to spatial analysis, and trying to follow this tutorial to generate a topographic wetness index for my area of interest: http://gracilis.carleton.ca/CUOSGwiki/index.php/...
0
votes
0answers
393 views

Use a WMS raster in ArcGIS 10 and combine it with vector layer

I have connected to a WMS server which provides raster images, more specifically, LIDAR surface elevation maps. I also have a vector layer which contains the outline of buildings. I would like to ...
0
votes
0answers
956 views

Manually edit cell value in DEM in Arcmap10?

Is there any chance that I could manually pick a group of cell in DEM, then edit the value of them in Arcmap 10? I know about the Aris Grid Editor for Arcmap but it requires licence and it's too ...
0
votes
0answers
60 views

Problem with Georeferencer not scaling TIFcorrectly

I am trying to use QGIS and the Georeferencer to digitize paper maps but I am unable to get the raster to rotate afte I pick my control points. Below is a brief outline of the steps I used to ...
0
votes
0answers
37 views

QGIS: Unable to project raster layers correctly on a Toshiba Tecra 64# Win7

I know how to project a raster, I can do it on other machines. On this particular machine the raster loads but are no where near the correct position as if the datum is on another planet.
0
votes
0answers
189 views

Display raster outlines

I guess mine is a very simple task, however I don't know how to solve it. I m trying to display the outlines of a raster created from a polygon shp. What I would like to come up with is an image where ...
0
votes
0answers
152 views

Searching Pixel Location (idrisi) on Another GIS

I'm Searching similar command Pixel Location (like idrisi) on Another GIS, I, need create raster file with values ​​lat, long by separately... Update: I need a raster file where the value of each ...
0
votes
0answers
1k views

How to resample a raster in QGIS?

I've got a boundary file that I would like to resample the raster file from a 30m grid to a 10m grid inside the boundary file. When I try and do it in Qgis or Grass all I get is one big raster cube ...
0
votes
0answers
217 views

Calculate optimal paths between different points

How can I calculate all the possible paths between a group of points, taking into consideration the SRTM and the Slope ? I am trying to do this in ArcGIS, my dataset is a group of points (shape ...
0
votes
0answers
239 views

QGIS Georeferencer and Coordinate Systems

I'm having an issue with Ubuntu and Windows versions of QGIS where the georeferencer does not properly assign the coordinate system to the output raster. When I assign the output CRS to 'EPSG:900913 -...
0
votes
0answers
274 views

QGIS Invalid Data Source in raster calculator

I just installed QGIS and am new to it. I want to use the raster calculator, but after assigning a name to the output layer QGIS tells me "Invalid Data Source" and "filename.tif is not a valid or ...
0
votes
0answers
207 views

SAGA grid VRT, file how to apply a LUT?

I've created a heap of saga grid files for some hydro survey work. I'm looking at a way to read these into a mapguide raster/grid layer, I'm able to load up the grids using a vrt file, I can't figure ...
-1
votes
0answers
29 views

Iterating columns and feature to raster conversion?

I cannot do iterations on fields correctly. The fields contain rain intensities. Each field represents a time ... 15 minutes, 30 min, 45 min .... I have 50 fields. I want to end with 50 raster ...
-1
votes
0answers
27 views

Merge village level shapefiles by sub_district_ID to get a new shapefile using R

I am new to using R for manipulating shapefiles and need help with merging the areas inside the shapefile to a superset based on the sub_district_IDs and get a new shapefile.