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

learn more… | top users | synonyms (1)

1
vote
1answer
8 views

Is this a known issue in gaps between masked raster and spatial polygon in R with mask command?

This is my codes raster file: RAD polygon(shape): ws_sfc RAD.sub <- crop(RAD, extent(ws_sfc)) plot(RAD.sub) RAD.sub <- mask(RAD.sub, ws_sfc) plot(RAD.sub) plot(ws_sfc, add = TRUE) ...
1
vote
0answers
72 views

NAs not allowed error message in attempt to plot raster object in R

I have imported a clipped raster (performed in ArcGIS 10.1) from the National Landcover Dataset into R, but when I try to plot I get the following error message. Error in .readCellsGDAL(x, ...
0
votes
1answer
17 views

QGIS qgis.utils.iface.addRasterLayer

When adding a rasterfile with QGIS python console there appears an error when the first letter of a rasterfile to be added is not written in capital letters. Why this behaviour? Example case1: ...
2
votes
0answers
20 views

Convert las files to ASCII raster format with the same cell size?

I am following the steps in this blog, but I cannot complete the Grid Difference step because my DSM and DEM have different grid systems. I have las files with almost the same area extent, but when ...
0
votes
0answers
9 views

How to calculate a raster area with Grass - help for query by coordinates

I'm working with Grass. I have a raster digital elevation model and I have analyzed the watershed flow. Now I have to: calculate the watershed area; find an identity in the digital elevation model ...
0
votes
1answer
18 views

removing spurious lines in raster before or after vector conversion?

I'm looking for a feature/function in either python opencv/ndimage/gdal/etc. or qgis/saga/grass that will help clean up a skeletonized image that I'd like to vectorize into a shapefile of ...
0
votes
1answer
19 views

Using ArcGIS Polygon to Raster tool does not divide resulting raster on cells?

I try to create raster composed of small (5x5 m) cells (pixels) from a polygon in ArcGIS-10. I created a polygon (as a single object), and use Feature to Raster Tool and Polygon to Raster tool (of ...
1
vote
1answer
15 views

Intersect shapefile with raster, then determine proportion of each raster value?

Using the arcpy module in Python, I want to find the proportion of each pixel value within the boundary of an overlaying polygon. (The polygon is in a shapefile.) For example, there are 10 possible ...
3
votes
2answers
222 views

Per-pixel (statistical) calculations on a raster stack using GDAL

In R, it's relatively trivial to perform per pixel calculations based on a raster stack (e.g., get std.dev for each pixel on a 12 layer GeoTIFF). Unfortunately, the speed is less than desirable when ...
0
votes
2answers
23 views

Aggregating rasters with GDAL

I have a set of files that have been mosaiced into a global VRT in a particular projection and resolution. However, I have a need to report statistics on a (say) one degree grid, where the reported ...
0
votes
0answers
8 views

TIMESAT input image requirement?

I tried to work on TIMESAT but always facing some problem. Here is the method i have used. Seems correct, but get warning at last. I have created a NDVI file from ENVI 4.8 >> Transform >> NDVI >> ...
2
votes
1answer
456 views

Create raster distance around a single point feature class

Okay, so I'm relatively new to ArcMap and I'm trying to use the Fuzzy membership for suitability test. I have a single point feature class that I want to use for this analysis. I know that in order to ...
3
votes
1answer
124 views

Continuous color band for a raster legend in QGIS composer legend

I'm looking for a way to insert continuous colour legend for a raster layer. I managed to create discrete symbols with values along the bar, but I would like to have a continuous bar with some values ...
3
votes
0answers
21 views

How to calculate 90% confidence interval in a raster stack

I have a stack of grid files (23) in ASC format from a MODIS sensor and I need to calculate a 90% confidence interval, mean, min, etc, for each one in R, how can I do that? specially the interval. ...
3
votes
0answers
55 views

Classified Images of RandomForest-Classification look clustered

I performed a RF-classification. I have 6 bands, ~250 trainingpoints in a shapefile, OOB estimate of error rate: 1.56% Picture of take trainingpoints added. My code: ...
2
votes
1answer
36 views

Processing RGB+NIR raster into RBG?

I have a Geoeye 1 satellite photo that's a 4-band multispectral B,G,R,NIR, 11 bit raster. Ultimately I want to publish this raster as a web service (using Mapserver). I opened up the raster in Qgis ...
9
votes
5answers
266 views

Raster diff: how to check if images have identical values?

Is there a means to check to see if any 2 given raster layers have identical content? We have a problem on our corporate shared storage volume: it's now so big that it takes over 3 days to conduct a ...
2
votes
3answers
35 views

How to increase raster extent by filling extent with no data using ArcGIS Desktop without Spatial Analyst?

I am using feature to raster to rasterize water polygons. It only makes a raster the extent of the features in the polygons, whereas I would like it to be the extent of another existing .tif image. ...
2
votes
1answer
560 views

Problem in importing raster data from PostGIS to Geoserver

I am using Opengeo Suite 3.0.2, PostGIS 2.0.3 and PostgreSQl 9.2. I am trying to import raster data from PostGIS to Geoserver but facing an error. I follow this tutorial link to import the raster ...
1
vote
0answers
22 views

How to Interpolate very large datasets in QGIS

I am working with a very large set of point data, (XYAttribute) which I wish to display as a raster. I've been using Interpolate, this is successful but very slow. I have other programmes that simply ...
0
votes
0answers
49 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 ...
1
vote
1answer
31 views

Flow accumulation raster loading in QGIS 2.4.0 with null values (but flow direction loading ok!)

I have been tasked with creating an open-source hydrology dataset for a community group. To do this I have exported the flow direction and flow accumulation rasters from ArcMap as TIFF files and then ...
2
votes
2answers
418 views

Clip_management to raster extent outputs larger raster than raster extent

Using Python and ArcMap 10.0 SP5, I'm trying to reproject and clip a large input raster to exactly the same grid as a smaller target raster (same extent, pixel sizes and projection). The problem is ...
3
votes
2answers
64 views

Merging raster and vector not working

I have 1 vector layer (counties) and 1 raster layer (population density). I have tried merging these two, so that I can examine population density within a county, but I have had no luck. It just ...
0
votes
2answers
99 views

How can I see average of raster value over certain area, marked by mouse?

I have a raster in Quantum GIS and I am just exploring it. How can I see average of raster value over certain area, marked by mouse? In other words: How can I select particular area in QGIS? How can ...
2
votes
0answers
32 views

Using R to subtract the polygon area of one shp file from another

I'm looking to produce a map from two separate maps in R. My Maps files are as follows: ftp://ftp.cpc.ncep.noaa.gov/GIS/us_tempprcpfcst/610prcp_20140822.zip #Map1 ...
-1
votes
0answers
22 views

Measure Displacement in ERDAS Imagine

How do I measure the displacement between two images in ERDAS Imagine. What tool do I use? I have looked in the ERDAS field guide.
0
votes
0answers
21 views

IMG and geoTIFF raster extraction

everyone. I'm very new to GIS technologies. Somehow, i need to extract raster(RGB data) data from geoTIFF and IMG files. What is the fastest way doing it?
3
votes
1answer
219 views

How do I write XML metadata with Python?

Some Python software I have written generates raster files via GDAL. I would like the software to create an XML metadata file for each raster so that I can include details about how the raster was ...
3
votes
1answer
42 views

How to model a geodesic grid in PostGIS?

Abstract I've decided to use PostGIS for a hobby game project. It requires a lot of units allocated on the surface of a planet. I'd like to model not only the units (simple points), but also their ...
3
votes
1answer
223 views

Can ArcGIS handle missing values to create a contour map?

I am trying to create a contour map for a waterbody. It turns out that in several locations there is no data. I just don't want to use the missing values as zero in ArcGIS because it would create ...
9
votes
2answers
432 views

What is the correct way to convert a USGS Orthoimage from WorldImage format to tiled GeoTiff for GeoServer?

USGS provides different resolution orthoimage quadrangles in the WorldImage format (*.tif with an accompanying *.tfw world file). Some of these quadrangles can be used by GeoServer (2.1.0 - 2.1.2) by ...
1
vote
2answers
36 views

How to produce “SpatialPixelsDataFrame” from stacked RasterLayer?

How to produce "SpatialPixelsDataFrame" from staccked RasterLayer ? I have a stacked rasterlayer and I want to convert them to SpatialPixelsDataFrame. RasterLayer information is > RAD.all[[1]] ...
0
votes
1answer
167 views

How to draw a custom map on top of base layer

I'm looking for the easiest way to draw a custom layer and export it as a tile cache. Basically what I would like to be able to do is load a base layer, and then draw objects and annotations on top ...
4
votes
3answers
488 views

Finding outliers with wrong Z values in LIDAR data

I have more than 2000 XYZ (only ground points) .txt files and I have to do Quality Control (QC). Let's say I have file, which I converted to multipoint (or even singlepart feature). I have mean Z ...
1
vote
0answers
24 views

Postgis Raster Unions Color Issues

Can someone explain to me what I am doing wrong here as I think I do not properly understand postgis raster bands. I have a set of geometries that I want to merge with a raster and created a raster ...
2
votes
2answers
92 views

Reprojecting Natural Earth raster into natearth projection with gdalwarp causing black squares?

I'm trying to reproject the Natural Earth 2 raster layer (http://www.naturalearthdata.com/downloads/10m-raster-data/10m-natural-earth-2/) into the natural earth projection ...
1
vote
1answer
85 views

Step-by-step: How do I extract Raster values from Polygon overlay with Q-GIS or R?

I am writing my master thesis at the moment and am having the exact same problem as user Curley in this question: I first need to overlay a Corine 2006 raster with a polygon layer (2638 polygons). ...
4
votes
1answer
198 views

How to change field name in raster file?

I´m having a bit of an understanding problem with a DEM TIF file. I have a DEM TIF file which is served with Geoserver. When I click on the layer the WMSGetFeatureInfo gives me the following output: ...
4
votes
2answers
66 views

How to access raster NoData value?

I am trying to programmatically access the NoData value in a raster dataset as shown in the screenshot. Two tools that come to mind to describe raster properties do not seem to be able to describe ...
0
votes
2answers
62 views

R -plot 12 images per plot or save 12 images per image file in R

Here is R script and my question is How can I plot 12 images per plot or save 12 images per image file because I have total 864 images. RAD1998 <- raster(paste(getwd(), "/1998bil ...
0
votes
1answer
90 views

I don't find the mistake in my RandomForest-classification

I am trying to make a RF-classification of aerial-imagery to specify tree-species. I extracted 3 bands and made a .csv file with columns: band1 band2 band3 x y class The band columns include ...
1
vote
1answer
167 views

problem with layers and variables box in raster calculator

I have a problem with layers and variables box in raster calculator. The layers and variables box does not exist in the raster calculator window! So I can not add any raster to the expression. I am ...
2
votes
1answer
35 views

Map algebra from files in multiple directories

I'm a rookie in python programming. I want to do map algebra for multiple rasters but these rasters are in different folders. Here's the code ive created so far: #Importing modules import arcpy from ...
2
votes
1answer
65 views

Levelplot(RasterVis) two marginal plot scale?

How can I add/display scale to two marginal plot? RAD1998.all <- stack(list.ras) list.files <- mixedsort(list.files(paste(getwd(), "/1998bil/", sep = ""), full.names = F, pattern = ...
2
votes
1answer
24 views

How to read raster datasets from ESRI geodatabase with FME?

I have a file geodatabase (10.2) with gdb feature classes as well as geodatabase raster datasets. I am using the Esri Geodb API reader in FME Desktop 2014 to read feature types from this geodatabase. ...
0
votes
0answers
25 views

Ortho-rectification of Aerial Image

I took an aerial image of our farm using RC quadcopter. How am I going to orthorectify this image? Please can you help me with detailed instructions/methods involving the process.
2
votes
1answer
36 views

Rasterizing Contours - How to remove 0 values

I want to convert vector contours to a DEM. From other posts, I wanted to utilise the Grass r.surf.contours tool. Initially I converted the vector contour layer to a rasterized contours using the ...
3
votes
2answers
48 views

How are kappa and overall accuracy related with respect to thematic raster data?

I recently calculated kappa (using confusionMatrix{caret} in R) between a thematic raster dataset at 1m spatial resolution and another at 30m spatial resolution. I was interested in quantifying the ...
3
votes
1answer
275 views

ArcSDE - How to edit mosaic dataset

I have a mosaic dataset (Raster) in an SDE database. As expected, when I click start editing, ArcMap says that I have to do "Register as Versioned" before, but I can't have a mosaic dataset in a ...