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

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6
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2answers
186 views

How to automate creation of toe of slope from DEM?

I was looking for an automated process to "identify" the toe of a slope from a DEM and ran across this ESRI thread and technique: I am at Step 7 but have no idea how this is accomplished. I get it is ...
1
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1answer
179 views

How to calculate the sum of all cells in a raster layer upstream of a specific point?

I have a rainfall map which covers large area. However, I'm interested in the total value of rainfall over a specific subcatchment. If I don't have the shapefile which defines the boundary of this ...
4
votes
1answer
2k views

How do I fill gaps in a raster to zero value cells?

I am trying to add some forest elevations to a DEM using ArcView. I have converted a polygon feature class of a forest into a raster with the same resolution as my DEM. Then I reclassed the forest ...
2
votes
2answers
555 views

Rasters added to mosaic dataset only display at large acale

I have a set of 357 rasters in .jp2 that I've added to a mosaic dataset. All but 7 of them display properly, but the 7 only display at larger scales, around 1:6500 and under. I've tried adding them ...
1
vote
1answer
526 views

If I convert a TIN to a raster in ArcGIS will results from the two versions of the surface be comparable?

I have converted a TIN to a raster. I found that the top of a bund wall shifts laterally in position between the TIN and the raster into which it has been converted using the TIN to raster tool in ...
1
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1answer
1k views

Use of Raster Calculator in ModelBuilder

I have the following equation: 3000*(1-exp((-0.000664)*input raster)) I want to make a tool to use this equation on raster images. I want to do this with the Raster Calculator with the help of ...
0
votes
1answer
82 views

Can I export an imagery directly to a geo-referenced raster form File|Export Map in Arcmap?

While using File|Export to export an imagery to raster, is there a way to have it geo-referenced in a way that if I load the exported raster into the map, the image sits exactly in its place without ...
3
votes
1answer
508 views

converting vectors to raster (burning streams)

I converted my stream vector to a raster file (using polyline to raster conversion tool). I anticipated that I would get a No Data row in the raster file attribute table, so that I could use a ...
3
votes
1answer
6k views

Is there a way to export online ESRI basemap layers to raster?

I have been working on polygonizing the vegetation areas in some counties from imagery. When I have the mosaic raster locally I can easily get the polygons using Image Classification Toolbar. But when ...
2
votes
1answer
69 views

How to choose an area (of mxn metres) within a raster that have values above a certain range

I've got a raster of concentrations of iron on Mars and I want to be able to choose several areas of either m by n dimensions in metres, or just any area in m^2, that encapsulate regions that have ...
7
votes
2answers
7k views

How to make RASTER from irregular point data without interpolation

I was trying to make a raster image from an irregularly spaced point database. The data looks like- > head(s100_ras) x y z 1 267573.9 2633781 213.29545 2 262224.4 2633781 ...
4
votes
1answer
2k views

How to perform a Cost Path analysis in ArcGIS 10.1?

Is it possible to model the easiest pathway through a landscape between many points (rather than just two)? I want to carry out a cost-path analysis, I would like to display the easiest pathways ...
1
vote
1answer
187 views

gdal_rasterize using a “string” as src_datasource

I would like to use a string as src_datasource for gdal_rasterize program. Is it possible to use something like a WKT definition to translate a single point to a raster? Somethink like ...
2
votes
2answers
3k views

Iterate through multiple Raster files and compute statistics using Zonal Statistics

I have a large number of raster images. What I'd like to do is to compute statistics on different sections of these raster files using a polygon. I think everyone is suggesting Zonal statistics. ...
1
vote
0answers
116 views

Color blending/compositing in web mapping frameworks?

The color/layer blending capabilities of QGIS 2 produce marvelous results. Blended rasters are especially nice to look at. Blending is, to me at least, a better way of combining layers than mucking ...
1
vote
3answers
834 views

Cache generation failed. Progress gets stuck at 0%

I'm trying to publish a map service containing a large .tif raster (48GB). I managed to publish a small cached raster successfully (for testing), but when I tried to publish the large one, the cache ...
2
votes
1answer
454 views

Wrong values in Feature/Point to Raster

I've got an XY dataset that I'd like to convert to a raster, based on the ETrel_whol field. The ETrel_whole field includes NaNs and ranges from 0-1. I would like to convert this to a raster, with a ...
1
vote
1answer
151 views

How to build and pass remap for floating point raster without getting Reclassify ERROR 010255?

I am receiving the following message when executing my python script: ERROR 010255: String remap must be used with a string field. My input raster is floating point and I would like to ...
2
votes
1answer
141 views

How do I create smaller maps for publishing from multiple tiles representing a large map using QGIS?

I am completely new to cartography and QGIS - I'm a writer, editor and acceptable designer (Adobe Creative Suite). I wish to produce PDF tour guides featuring maps that display a route. One version ...
7
votes
3answers
3k views

Merging hundreds of Aerial Photos into one big file?

I have tried to merge my 405 Aerial Photos into one. I have FME and ArcInfo 10.0 at my disposal on Windows 7 64bit. I have tried the following: create a mosaic; export all images from a rastercatalog;...
0
votes
0answers
55 views

Warping Rasters in QGIS

There seems to be a bug warping rasters in the new QGIS version 2.0 When you have to option of target and Source SRS, the Coordinate reference system does not get automatically writen into the box ...
2
votes
1answer
480 views

Tabulate Area for large datasets

I have been struggling trying to use Tabulate Area in Arc 9.3 for a large raster dataset. I have one raster with 8 land uses and another vector layer with zones (which I converted to a raster with ...
1
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0answers
156 views

Mann-Whitney U test for rasters

I'm doing a Mann-Whitney U test to compare two very large samples (sample size 1 = 13250; samlple size 2 = 38871) originating from a shapefile with 52121 features. I know t-tests are not recommended ...
4
votes
2answers
2k views

Efficient way to handle NA values from analysis in R with Raster

I am not 100% sure if GIS is the correct stackexchange for this, but here we go. A problem I have been bested by: I have a raster layer of approximately 240 million cells. It could be a DEM or ...
3
votes
1answer
2k views

Service published but cache generation failed on ArcGIS Server

I am trying to publish a map service containing a cached raster layer on our ArcGIS Server Enterpise 10.1. I analyze the map service before publishing and no error. The error I get when publishing ...
2
votes
1answer
106 views

resampled thematic map accuracy

I've generated a map of ecoregions based on some environmental data using a semi-supervised classification where I combined a statistical clustering with random forests to generate my map. I created ...
6
votes
2answers
835 views

How to de-noise a DSM

I have created a DEM, DSM, and nDSM from a LiDAR Point Cloud using SAGA-GIS. I extracted the appropriate returns from the point cloud, then converted to grid, and then closed gaps to fill in any ...
4
votes
2answers
255 views

Problem overlapping shapefile and vector in R

I want to plot a shapefile over a raster file in R but I can't make them overlap perfectly: the raster appears to be rotated of few degrees counter-clockwise. Is it a problem with the projection? ...
3
votes
0answers
178 views

Calculate surface elevation from DEM of pit and known volume with which it is being filled

I am using ArcGIS 10.1. I have a DEM of a pit. I have a known volume of material that I want to put in the pit. I want to know what the elevation of the flat surface of this material will be ...
2
votes
1answer
447 views

Does ModelBuilder need to use variable to define projection and then re-project?

I am trying to build a Model in ModelBuilder to create two different process raster datasets: One set is to define a raster dataset to set a WGS 84 projection; and then the second set is to take ...
1
vote
1answer
3k views

How to Build Raster Attribute Table from .tif with pixel type of float or double?

I have a raster with the extension .tif. It's a subset of 87x87 pixel with values from some 6,66 to -4,27. If I right click on it there is no Attribute Table available. However, I can change the ...
4
votes
1answer
511 views

How to create Series of Rasters that displays Standard Deviation from Mean?

Cell statistics question for you. I have 100 rasters of raw rainfall data in which the pixels each represent rainfall for that particular pixel on the landscape for a single year during the 100 year ...
2
votes
5answers
2k views

How to export raster from PostGIS enabled DB as GTiff with gdal_translate

When I want to export a GTiff from my PostGIS DB with this code: gdal_translate -of GTiff PG":host='localhost' port:'5432' dbname='landslide' user='postgres' password='pass' schema='public' table='...
2
votes
1answer
110 views

Raster clipping over 1300 km2 orthophotos

I have all of Denmark in 25 cm orthophotos added to my ArcMap (mosaic dataset). I've added a polygon of an area covering over 1300 km2. I've used the raster clip tool to clip the data into a new ...
2
votes
0answers
273 views

How to write script for Line of sight and Viewshed analysis in Global Mapper

I wanted to write script in Global Mapper for Line of Sight and Viewshed analysis. I tried to calculate using Viewshed and Global Mapper Tools but the issue I am facing is that analysis is user ...
5
votes
1answer
1k views

GDAL polygonize lines

I have a raster file containing roads (left image). I polygonize the raster file with GDAL (see the script below). In the end I like to have vector lines. However GDAL only gives me something like ...
2
votes
1answer
815 views

GDAL polygonize only certain raster values

I want to polygonize a raster file with GDAL. I only want to rasterize cells with a value of 0. Is it possible to specify that within the polygonize function or do I have to modify my raster before ...
5
votes
1answer
797 views

Generate hillshading with GDAL, and respect nodata

I'm still trying to nut out this problem of merging overlapping geotiffs. From the original dataset (here, a 20m resolution digital elevation model of the state of Victoria), I have reprojected it ...
2
votes
3answers
1k views

how to decrease Raster size without altering cell size?

Is there a way to decrease the size of a raster image without decreasing cell size or quality? I´m using ArcInfo but also have Saga-Gis or FME. I could abviously change an 8bit raster to a 1bit ...
2
votes
1answer
4k views

How to create attribute table for raster data?

I have raster dataset for rainfall but its not having attribute table. How can I create tabular data using the same raster file? How to join it back again to it? Software used is ArcMap 10.1.
2
votes
1answer
248 views

Arcpy.GetRasterProperties_management values do not match values found via ArcCatalog or ArcView

I am using Arcpy to extract the mean and standard deviation values of tiff Landsat satellite images and I get very high values. Values in the thousands rather than in the low hundreds! If I look at ...
1
vote
0answers
214 views

How to Iterate ModelBuilder for Zonal Statistics?

I want to use ModelBuilder to split a DEM into multiple tiles, then run the iterator on each tile made for the Zonal Statistics tool to find the highest point(s) in each tile and give these as an ...
0
votes
3answers
391 views

Grouping Multiple Raster Layers

My question is how to create multiple raster layers group, for example when using several aerial photos. I wish to group the layers into one so that I can edit/select as a batch rather than having to ...
0
votes
1answer
82 views

ArcGIS10 Highest point via polygon features

I am using ArcGIS 10.0 with 3D Analyst, Spatial Analyst and Military Analyst. I feel like I am halfway to solving a problem but do not seem able to completely solve it. I have a polygon shapefile ...
2
votes
1answer
539 views

Convert multiple Shapefiles in Raster in R(and then plot it)

I'm trying to convert several shapefiles in rasters at the same time. I already was able to read the shapefiles by doing this: library(maptools) shps <- dir(getwd(), "*.shp") for (shp in shps) ...
4
votes
1answer
507 views

How to reclassify a raster (tiff) with multiple bands?

i have a raster file containing information about the windspeed average for the year. My purpose is to reclassify the 15 classes based on their rgb-composite. The color is the only information given. ...
1
vote
1answer
718 views

ArcMap Raster to NetCDF - lat/long

I need to convert a few files which are projected in WGS84 into netCDF. NetCDF requires lat/long. I am a bit confused on how the process is handled by ArcMap especially after looking at the online ...
1
vote
1answer
417 views

Why does georeferencing reduce the image resultion?

I'm trying to use a raster as a base image in my QGIS project. It is a building schematic which is fairly high resolution. Importing this into QGIS, it seems that the only way to re-position an ...
1
vote
1answer
61 views

Needed a free high resolution imagery for Las Cruces, New Mexico area

I'm Looking for a free download Imagery that is a very high resolution and the most recently like the past 3 months. I'm doing to produce a map where our new building being move into next year ? Is ...
1
vote
0answers
260 views

Why are the colors of my WMS layer messed up in QGIS?

I have a raster image on my computer, and I used it to test some geoserver features. (I'll upload images to show you what the problem looks like) I have the same raster, but transferred by wms. And ...