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

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2answers
44 views

How to bulk upload raster datasets to ArcGIS Online as separate discrete layers?

I have 18 raster datasets which I need to publish through ArcGIS online to allow users to turn on/off each layer and toggle transparency. I have the data stored in a file gdb as below: I am looking ...
2
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1answer
48 views

How to create azimuth raster layer by pyqgis?

I want to create an azimuth raster layer base of single point shapefile, for this I write below code that create a memory point layer that each point in memory layer is center of each pixel and have a ...
0
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1answer
29 views

Why do collinear ground control points create larger residuals?

When georeferencing a raster image of a long corridor, why do collinear ground control points cause larger residuals? Say I am using the georeference function in ArcMap, and I have 6 ground control ...
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0answers
11 views

How to avoid the quilt effect when displaying imagery from multiple source

In the context of creating my own imagery viewer (for educational purpose), I would like to learn about the process used to create seamless transitions between satellite imagery tiles coming from ...
1
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0answers
33 views

how to extract line features from a raster

I have a raster of land cover types where roads are represented by pixels (1 pixel = 25m x 25m = 625 m²). Is there a way to extract line features (here roads) from a raster ? ## Create raster as an ...
7
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3answers
291 views

Is there an efficient way of sending a large raster image?

Rather simple question: I have two large raster images that are stored in ArcSDE. I need to send these images to someone else, and post it on their ftp site. What is the most efficient way to send ...
1
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0answers
36 views

How to automate the QGIS Raster Interpolation Plugin using python console?

I have a rainfall data from 1961 to 2015 for each day of this years. I need to create a raster for each day with this configuration. Do you know how to automate this using this plugin and python?
3
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1answer
79 views

Error while comparing two raster layer in R

I have got a geographic point distribution with N prehistoric settlements with a size of x and want to compare the distribution with an economic simulation, which produces M settlements (Usally N > ...
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0answers
40 views

Spplot SpatialPolygonDataFrame and SpatialGridDataFrame

I have to plot in the same graph something like this: Then, I have elements from SpatialPolygonDataFrame class and others elements from SpatialGridDataFrame class. When I try to plot them in the ...
2
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2answers
42 views

Use function spplot

Does anybody know how to plot with "spplot" fuction two elements of diferents classes?. One element from "SpatialPolygonDataFrame" class and other from "raster" class.
0
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1answer
27 views

R: raster stack (time series) loop pixelwise and write layer number of value occurence into a single output layer

I have a raster stack of gridded RFE 2.0 rainfall data (time series of one year = 365 layers). Now I wanted to identifiy on which date during the year the first rainfall occurs for each Pixel. The ...
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1answer
41 views

High res monthly satellite maps including ice cover

I have some old month by month NASA satellite maps showing the world in 2004 at 5400x2700px. I've noticed NASA has newer cleaner versions of these maps at ...
2
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1answer
46 views

Storing and updating large amount of raster data

Large amount of data = ~10TB of rasters (multiple projections) with the possibility of this data growing. The basic architecture I'm planning at the moment is having 2 clusters of GeoServer--one ...
1
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1answer
67 views

ArcMap aerial raster image exposure is off

I have some aerial raster images and I want to create tiles for web. So I added images as layers in Arcmap and as the result some images were overexposed with different lightness. For comparing I ...
1
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0answers
16 views

Import raster using raster2pgsql with out-of-db option not working

I am using raster2pgsql to import DTED data into postgis database. I would like the data to be out-of-db, I am using the command as follows. raster2pgsql -R /home/gis/elevation/DTED/area.dt2 ...
2
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1answer
68 views

Raster statistics for polygon areas PostGIS

I'm trying to get zonal raster statistics for each polygon area. I have used the following method from this site: SELECT bufid, (ST_SummaryStatsAgg(ST_Clip(rast, geom, true))).* FROM rasttable, ...
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1answer
19 views

Calculate the frequency of classes of neighbouring raster cells

I'm struggling with a problem when working with a raster dataset of biotope types: For each cell I would like to find out the frequency of classes in the adjacent cells, e.g. from the 8 neighbouring ...
4
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1answer
55 views

Why does an 32-bit FGDB raster have a smaller file size than 8-bit?

Using Arc 10.0, I have a single band, 32-bit signed raster as the only item in a file geodatabase. Using ArcCatalog, I copy that raster to a new geodatabase with an 8-bit unsigned pixel type. As ...
6
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2answers
157 views

How to speed up this script in QGIS?

I am a new in PyQGIS, I want to create a Point layer from a raster layer. In table of point layer created, there is 3 fields by name of "X_coord", "Y_coord" and "Azimuth", each point in Point layer ...
3
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1answer
32 views

How to combine 2 vector shapes created from raster files

In Qgis 2.12 Lyon, using windows 10 I downloaded 2 raster files from an area of my interest. The rasters were on information about precipitation and evapotranspiration. Each cell had a value. I ...
4
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1answer
60 views

GRASS GIS temporal raster individual layer statistical summary

I have created a temporal raster in GRASS GIS which has 90 layers. I would like to extract the mean of each raster layer and export it as text file. Right now I have to export the rasters as GeoTiffs ...
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0answers
33 views

QGIS polygonize tool not working [closed]

I am having a problem using QGIS ver 2.10.1 Pisa. I am trying to use the polygonize function on a raster .tif image, and it runs, but only produces a thin sliver of polygons at the top, then stops ...
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0answers
8 views

Created raster with not expected range

I have created a raster layer with kriging tool as source of data have localized sapefile attached and shown in Figure. Why the value range and are produced raster information is irrelevant to the ...
9
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2answers
208 views

Make several rasters more uniform

I have imported some rasters that is supposed to be continuously connected but instead they create some sort of bordered grid between them. I may assume that this is a matter of calibration between ...
1
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1answer
52 views

Change NODATA values to 0 in Qgis

I know this question has been asked already in this forum, but I couldn't find an easy (for me, a rookie) solution for my problem. I have an RGB 3 band file which, in some pixels, has i.e. R no data ...
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0answers
19 views

how to generate a raster with its spatial reference from an array(or matrix) by using pyqgis

I used arcgis to generate rasters from txt files by a certain python api,but i am not familiar with qgis,and now i need generate some rasters from txt files by using pyqgis.The resulting rasters ...
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0answers
28 views

How do I create a raster file from a geopandas dataframe storing lats, longs, values, and geometries

From a text file with time, lat, long, and cf values, I create a pandas dataframe (cf_df). Then I use the lat, long values to create a geoseries and create a geopandas dataframe from the original ...
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0answers
13 views

Export RAT (KEA driver) to Shapefile

I have a dataset of rasters (driver kea) whose has, let's say, 20-30 attributes in their RAT. I'm realizing how to have these attributes in shapefiles (without using proprietary software). I've read a ...
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0answers
35 views

R Efficient Way to Resample, Crop, and Mask a Raster Image

Does anyone know an efficient way to resample an image? I am currently trying to crop a large image and clip 2 regions from a shape file. From this clipped image, I would like to increase the pixel ...
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1answer
31 views

Area estimation using raster image

I have a map of trace gas (NO2) distribution over big cities and other anthropogenic objects. The purpose is to estimate the area of distribution. I attached the sample image to illustrate what I do. ...
0
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1answer
39 views

Reprojecting and retiling a large set of tiles

I am trying to understand the process to re-project and re-tile a set of raster (GeoTiff) but can't wrap my head around how to use the different GDAL tools to achieve my goal. More concretely, I ...
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0answers
31 views

Get distances between boundaries from an SpatialPolygon and raster pixels

I am trying to calculate the distance from several pixels of a raster to a boundary of some polygons in R as it is showed in the image. I have two problems: How to correctly define a boundary from ...
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2answers
38 views

R calculate raster cell size in map units

I have a RasterLayer and would like to know the cell size. I haven't find any function in the packages :-S . Does someone have an idea ? info about the RasterLayer class : RasterLayer ...
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1answer
33 views

Exporting a raster with renderer enabled to file

I have a problem when trying to export a layer with renderer to a file. Basically, what I have at start is a correct IRasterDataset. Then I define a stretch renderer in form of IMultiPortColorRamp and ...
3
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1answer
39 views

Raster Layer Statistics CSV Output using QGIS Graphic Modeller

I am currently working on a project where I am using historical cloud coverage from MODIS Cloud Fraction data to try and estimate future cloud coverage of any particular month. I currently have ...
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0answers
17 views

Access MEM data from GDAL?

I don't have any answers (yet) from from previous question on GDAL memory raster + OpenLayers, so i'll try to ask an easier question :) Anyone knows how to access GDAL memory with command lines when ...
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0answers
17 views

Raster colormap setting in Arcmap not honored in GP tool

I am working with digital versions of paper maps. Here is what I am attempting to do: In Arcmap determine the value in a raster's colormap that is the undesired black mask / "no data" section. Set ...
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1answer
20 views

My raster does not line up with rest of vector shapefiles, even though both rely on NAD 83

I started creating a map in ArcMap by adding vector shapefiles. All of my vectors have data sources as: Data Type: Shapefile Feature Class Geometry Type: Line Projected Coordinate System: ...
0
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1answer
27 views

Defining the correct AEA proj4string for FEWSnet Rainfall Data (Southern Africa) in R [closed]

I have some general questions about how to go about solving this problem: I am trying to incorporate FEWSnet's monthly Rainfall Estimate data from 2014-2015 for Southern Africa into an analysis where ...
1
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2answers
44 views

R: aggregate raster with 'mode' function - how does it work?

I want to aggregate a very fine resolution raster at various coarser resolutions (that represents many 1000s of categorical polygons). The aggregate{raster} function is what i've traditionally used, ...
1
vote
1answer
28 views

Why doesn't Ordnance Survey street view raster layer appear on qgis map?

I've downloaded the relevant 100 km square of OS Street View raster data and have added the relevant 5 km square to a QGIS 2.8.2 map of scale 1:1500. The layer can be seen in the layers menu but not ...
3
votes
2answers
36 views

What is the SRID of LCC projection?

I have a raster file with LCC projection and a point dataset with SRID 4326. I want to extract raster value to point. When I use the query SELECT ST_Value(rast, geom) val FROM testraster5, ...
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0answers
7 views

mapnik.Gdal(file=my_latlon_raster_file_path) returns a datasource with an empty all_features() list

When I get my mapnik layer datasource like that for a raster file: layer = mapnik.Layer(my_raster_layer_name) layer.srs = my_srs layer.datasource = mapnik.Gdal(file=full_path_to_my_raster_file) and ...
2
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0answers
33 views

Extracting Mean from Raster and Writing to Table in ArcPy?

I am simply trying to extract the mean of each raster within a geodatabase and write the value to a table. I have done this successfully with another set of rasters, but now I keep getting the ...
0
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1answer
24 views

Masking low quality raster with polygons in R gives weird overhang?

I am pretty new to R, and have been attempting to use the mask function on a raster image of 250mx250m resolution. My problem is that for some reason I am getting overhang, as there are pixels which ...
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0answers
28 views

How to generalize a raster with noisy edges with ArcGIS Desktop?

I'm trying to generalize a raster to get clean edges (see sample and "optimal" result below). However the borders bleed into each other to a rather high degree. I hacked away at the raster using ...
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18 views

Choosing pixel size when projecting raster from geographic to projected coordinate system

I have a raster showing animal abundance in all of Canada. The raster was created unprojected in GRS 80 with a pixel size of 0.0833 decimal degrees. I was ask to project this raster to Canada Albers ...
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0answers
23 views

Polygon to Raster tool while keeping less than maximum values

I'm trying to convert a very large, detailed polygon to a raster with a coarser resolution in ArcGIS 10.1 using the polygon to raster tool. The value field is a percentage and the cellsize must be the ...
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0answers
23 views

St_intersects returning false results in postgis

I want to intersect point geometry with raster. In postgis I'm executing select st_intersects(geom,rast) from testraster1,pft_pft and the result is false even though the points are sitting on ...
2
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1answer
40 views

Automated clearing /tmp using QGIS batch processing?

I'm currently batch processing a bunch (~200 x 200MB) of ascii grid surfaces using some SAGA and GDAL algorithms in QGIS and have been running into "out of storage" errors. The issue is that between ...