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

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levelplot index issue

levelplot with static index works fine but not in a for loop. What's wrong with my code? Static index: png(paste("1998",outlist[[1]],".png",sep="")) levelplot(RAD1998.all[[1:4]]) dev.off() png(...
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783 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 /...
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1answer
684 views

AttributeError: 'unicode' object has no attribute 'save'

I'm trying to multiply my raster to 100 from my ListRasters. I've adapted the code (especially the for loop portion) also from this site. Now, I'm encountering an error at the last line, when saving ...
3
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1answer
199 views

Highest DEM pixel in polygon

I'm working with QGIS and have a big DEM raster layer with height information and a vector layer with many polygons, representing 1 x 1 degree tiles. Now I want to find for every polygon the highest ...
2
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1answer
217 views

(How) can I write string data to a raster with Python/GDAL?

In Python, I have a NumPy array of string values (categories of some variable) that I'd like to write to a raster file (.tif or .img) using GDAL. The impression I get is that it's not possible to ...
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2answers
369 views

QGIS raster clip error: Cutline not of polygon type

I have a raster file and want to clip it, but I'm getting this error: "ERROR: Cutline not of polygon type" what does this error mean and how can I resolve it?
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0answers
68 views

Align & Sum Grids in Python

I have two grids. One, call it A, is 4320x2160 cells and spans the whole globe. The other, call it B is 8640x3432 and spans the circumference of the globe, but is clipped toward mid-latitudes. Both ...
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2answers
132 views

Reclassify a rasterList and sum the reclassified value from each Pixel

I'm trying to write a script in arcpy which reclassified a List of Rasters. This rasters are made by another tool before so there is already a loop. Actually I get the error 000582 and before this ...
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1answer
747 views

How can units be defined in QGIS for the Rasterize tool?

I am using QGIS 2.4 (Chugiak) via the kyngchaos build for OS-X. My question is--when using the Rasterize tool to convert a point vector layer to a raster and using the "Raster resolution in map units ...
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180 views

PostGIS Raster functions not working

Hopefully I have a simple question that I'm not phrasing correctly in google. I'm trying to learn about storing and producing rasters in PostGIS. There are tons of examples and documentation online ...
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1answer
203 views

Java how to create geotiff from points

I have an array of objects where each object has three fields: lat, lon, and category. It is essentially pixels that have been given a land use category. I cannot figure out how to turn this data into ...
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282 views

How do I parse the file format for attributes in Raster Product Format (RPF) maps and imagery?

I'm trying to implement an open-source NITF reader (using only java, no external libraries such as GDAL or NITRO), and its mostly going OK. However I'm having trouble understanding the RPF extensions, ...
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46 views

Looking for a QGIS solution to make aerial imagery ArcSDE compatiable [closed]

Would like to avoid having to use 3d Analyst and use free raster tools in QGIS or elsewhere to make aerial rasters ArcSDE compatible. This 18 page work flow is what I am trying to use. Any suggestions ...
2
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1answer
97 views

Speeding up loading raster

I georeference a tif image and then I clipped that image in a mosaic. I did a index of these images but when I load them is very slow(7 seconds or more to display the first tile). How can I do to go ...
2
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1answer
164 views

Error reading large virtual raster with rasterio: “Cannot invert degenerate transform”

I've created a virtual raster using gdalbuildvrt, which covers a large extent (England) at a high resolution. The data is fairly sparse, focused around the coastlines with no files covering inland ...
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203 views

Correlation between point feature (disease) and elevation

I have a problem! How can I calculate the correlation between point feature and Dem raster? Hypothesis: disease prevalence in high altitude is more than low altitude. I must do this in ArcGIS 10 and ...
2
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2answers
539 views

Setting background RGB value to invisible for multiple rasters in ArcGIS Desktop?

I'm using ArcGIS Desktop 10.0. I need to set my background rgb value of 255,255,255 to transparent. In the layer-Properties Windows > Symbology I can do it for one layer, but can I batch set this, or ...
2
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1answer
3k views

how to use gdal_rasterize? how to know which attribute to burn with ogrinfo?

I have a vector layer I need to rasterize. I guess this is a basic operation, but I haven't found the information I need yet. First, I have reprojected the vector shapefile: ogr2ogr -s_srs "+init=...
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0answers
198 views

Is it possible to change the default raster style of newly created rasters in QGIS?

If I do calculations on rasters with the raster calculator or other tools, the resulting rasters displayed in my canvas are always in the same default style (singleband gray, black to white...) so ...
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0answers
82 views

How to add a TIF raster layer programmatically?

This is my code whenever i try to load .tif image it shows layer is not valid,QgsRasterLayer always return invalid layer (I am using linux 12.04). QString myFileName = QFileDialog::getOpenFileName(...
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0answers
210 views

How to group a multiple rasters in MapServer?

I had a map files for each state (raster file) of India. Now I want group all mapfiles to show a single raster or single map file? How I can do in using qgis or any platform?.
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283 views

Is there raster equivalent to vector Intersect?

The intersect tool that is used on vector data cannot be used on raster data. What tool can I use for my two rasters that does the same as the Overlay > Intersect tool?
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1answer
69 views

Determine changes in land cover of isolated features over time?

I have a a study area of 2 Landsat scenes from 2013 which were classified for a specific natural community, and these areas have been isolated and extracted and digitized into vectors so that they can ...
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2answers
450 views

Use Values from Raster Statistics (e.g. sum of all cells) in Raster Calculator

I need to do calculations on raster layers which require the sum of all cells of the raster. I've used the zonal statistics tool for that but it gets a little annoying to do those extra steps (run the ...
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1answer
199 views

Con() does not recognize raster values

I have a problem when using the con() argument. What I want to do is to remap all raster of a raster file ("Red_SL") cells with values larger than 40 to the new value 5. All other values should be ...
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1answer
241 views

Iso Cluster tool in script failing to open clip raster

I have been coding in Python for only a few months, so maybe I'm just overlooking a minor detail as a newbie. I have written the script below for a class project. It is supposed to clip two rasters, ...
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99 views

Problem with adding mosaic layer via arcpy

I have a mosaic layer that I want to add to my map in ArcMap. When I add this layer manually (i.e the "Add Data" button), a raster image, a boundary, and a footprint are added to my table of contents. ...
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1answer
625 views

Cannot get 2 raster files of same cell size to align ArcMap 10.2

I have two raster files that are the same cell size but I cannot get them to align properly. (I want the black to line up with the pink) When creating the black raster file (from using polyline to ...
2
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1answer
296 views

How to find the projection of an image?

Instead of georeferencing the image and deforming it, I'm trying to find the projection used by the author of the image. I've got tens of these distribution maps to digitize. The idea is to avoid ...
2
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3answers
1k views

Use GDAL command line to copy projections

I have two images, a georeferenced Tiff and a second Tiff without a reference. The second image is a copy of the first, but it lost its reference. Now, I want to copy the reference from the first Tiff ...
2
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2answers
2k views

QGIS Raster Calculator: Need values to be set to 0 instead of no data

I have a landcover map with different values for the landuse options e.g. 190 for commercially used areas. Now I want to extract only these areas using the Raster Calculator with the expression "...
2
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3answers
268 views

Zonal Statistics as Table Tool

I have a slope dataset. I have a polygon shapefile with territory within the extent of the slope map. I have to calculate the real surface area of this shapefile using the zonal statistics as table ...
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179 views

Raster Calculator

I have a slope dataset. How do I calculate the real surface area for this slope dataset using the raster calculator. This is the example I was given: orthogonal area of a raster cell in square ...
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60 views

Polygonize Missing Polygons

Polygonize is not capturing all of the pixels in an image that has been converted to 0s & 1s. The pics below show -original geotif -geotif recalculated to 0s & 1s -polygonize output As the ...
3
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1answer
212 views

data source for worldwide cross-sections of topographic and bathymetric for woodworking art project?

i am a decent r programmer and statistician, i am able to work with data sets pretty well. i am less familiar with GIS tools, but if given a shapefile i can certainly plot political borders and ...
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121 views

Positioning and tracing polygons over an image

On QGIS 2.0 - I want to add an image (TIFF or whatever) then resize and correctly position it over a satellite image (openlayersplugin). Then, the task is to create a new shape file layer and draw ...
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2answers
136 views

polygon to raster - not all polygons rasterized

I have a building footprint shapefile (polygons) that I want to convert to a raster. I use the Polygon to Raster tool, and specify a cell size by importing from another raster (which is 24m x 30m). ...
3
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1answer
878 views

R giving error when attempting map algebra

I'm trying to manipulate some downloaded rasters using R, and keep getting the same error when I try to do any type of map algebra. The example below uses a raster file downloaded from http://www.csc....
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1answer
237 views

ERROR 000824 while trying to run IsNull Method outside ArcGIS?

I am trying to perform IsNull function to a raster using PyScripter. This is the code I use: import arcpy import arcinfo InRaster = "C:\\data\InRaster" IsNullRa = "C:\\data\IsNullRa" arcpy.gp....
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1answer
65 views

Raster Calculator Blurring Image Results

I am trying to run a NDVI analysis using raster calculator on Arg Map 10.2.1 and the results create blurry or bleeding image, almost as if the map has been dipped in water. I am using the default ...
2
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1answer
170 views

Counting overlaps between raster files using ArcPy?

Would it be possible to simply detect and count overlaps between raster files, i.e. not polygons against rasters, using arcpy? By default I don't have the spatial analyst extension for ArcMap 10.1 but ...
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2answers
507 views

gdal2Tiles output differs from MapTiler

I'm in need to process a large batch of Landsat images with MapTiler and since the version I'm using (1.0 Beta 2) does not support multiple input files, I created a simple python script that calls ...
3
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1answer
227 views

POSTGIS Raster - Merge polygon onto raster

I have two tables, SCHEDULE contains polygon geometries and RASTER contains raster tiles I want to take a polygon from the SCHEDULE table and overlay it on top of a set of RASTER tiles that intersect ...
3
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1answer
677 views

QGIS: Need to remove unwanted white bands when raster layer are overlapping

In my project when raster layers are overlapping a white band appears the edge of the top layer. How can I remove it and obtain a seamless overlapping of the raster ? (I have try to built a vrt with ...
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2answers
58 views

QGIS: how to identify a visible raster layer among large view (composition of rasters)?

I have QGIS project loaded with many raster files. For a given area, (ex: under my mouse pointer), I am looking for way to identify which (raster)layer provides the visible data. To start, I will ...
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1answer
543 views

How to do loops on raster cells with python console in QGIS?

I'm new here and beginner with python. I'm looking for a solution to my problem for some hours but now you are my last chance... I'm using the python (2.7.5) console in QGIS (2.4.0). Is there a ...
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124 views

analysis of srtm data for gaps

I need to analyse the SRTM DATA (1025 X 1025) of a particular terrain which has gaps or voids. Could anybody suggest a solution to find the percentage of gaps or voids in the SRTM data? I would like ...
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33 views

Text in POSTGIS Raster

Is it possible to add text/annotation to a raster generated in Postgis raster? Specifically I need to do this within the database if possible and am looking for an option that does not require an ...
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0answers
182 views

Polygonize only pixel values of 1 from a raster

I have a raster mask that I have created in QGIS (2.2.0) that consist of 0, 1 and nodata values. I would like to end up with a polygon dataset that consist of only the value of one pixels from this ...
4
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1answer
299 views

Projection mismatch when plotting precipitation with ggplot

I'm trying to plot accumulated precipitation in Brazil for a given period, see code below: Load packages library(raincpc) library(SDMTools) library(raster) library(ggplot2) library(rgdal) library(...