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

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541 views

Contour Lines Raster Extraction

I've been playing with Mapbox's blog post about converting heat maps to contour lines, and I'm stuck at the extraction part of this process. I used the CSV plugin to create a vector layer of points, ...
3
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1answer
217 views

gdal_warp of multiple rasters keeping maxium intensity value

I have multiple rasters which overlap eachother geospatially but do not completely occupy the same space. I can combine them with gdalwarp like: gdalwarp -s_srs EPSG:4326 *.tif larger_output.tif ...
5
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2answers
754 views

How to batch import GDAL supported raster files into GRASS?

I am trying to import some GDAL supported raster files into a binary raster map layer using the r.in.gdal module from QGis Grass tool. As I have multiple files to import, I would like to batch import ...
5
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1answer
618 views

How to get pixel size/cell size of raster layer?

After much searching, I've still not been able to figure out how to perform what seems like a simple function: I'd like to get the pixel size/cell size of a raster layer using PyQgis. Is there any ...
2
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1answer
369 views

Creating a quality raster map in QGIS?

I've got 2 raster maps (both with the same values: 0-100). After calculating the average I need to know how precise the map is. Is there any tool in QGis? I try to explain my problem in another ...
3
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2answers
72 views

How to make a copy of a temp raster in QGIS?

I have a temp raster (saga raster) file. How can I make a copy of this file (like "save as")? Thank you!
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0answers
154 views

Is there a way to create raster by interpolating point values using GeoTools 8.2?

im new in using GeoTools (8.2). I was able to create shp from asc file which contains my data. Now my question is is there a simple way to create (interpolate) a simple shapefile (only points) to ...
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3answers
2k views

Extract raster by mask output does not completely overlap the mask

I have a flow accumulation grid and a shapefile containing catchment areas. Now I want to do some calculations on them so I need to extract data from cells in the raster adjacent to certain catchment ...
5
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1answer
79 views

Is there an arcpy equivalent to IPixelBlock in ArcObjects?

Trying to figure out a way of doing this via arcpy, but don't see anything remotely related to this. My raster dataset is a GRID. 'pPixBlock is an IPixelBlock 'sets raster to be one column ...
7
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1answer
1k views

Smoothing raster features into polygon

I have raster data representing urbanized areas, which I'd like to trace and convert to a polygon. Using ArcMap's Raster to Polygon tool, I'm able to get something close to that. Unsimplified: ...
2
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1answer
263 views

joining a table from zonal statistics as table with a layer, problem with reserved names

I have a raster file (percentage of total forest killed) and a shapefile with polygons (municipalities). I thought as a first step I would like to find out which municipality shows the greatest ...
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1answer
653 views

Problem merging two rasters in Qgis

I have two rasters in Geotiff, same CRS. I tried to merge them and I have this error code ERROR 4: `C:/Anita_Tepoztln/Rasters/e142.tif' does not exist in the file system, and is not recognised as a ...
3
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1answer
88 views

V.kernel not working correctly in grass-6.4.2

I am using grass-6.4.2 for generation of heat maps of crime data. For testing purpose, I created a vector layer from my places shapefile which is a point data.The places shapefile contains more than ...
14
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2answers
2k views

Performing Raster Noise Reduction and Edge Smoothing?

I have a raster image like this I want to delete the isolated noise point and smooth the edge (say the white single points, and I want the edges of the entity look smooth). How can I do this in ...
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1answer
2k views

ArcMap 10 - Extract raster cells from imagery based on RGB value

I've got some aerial photography (format: IMAGINE Image) which is detailed enough to see to fire hydrants and a shapefile of fire hydrants which was digitized based on some CAD data. My project is to ...
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2answers
677 views

Spatial query of raster data

I have population distribution data as a raster layer and exposure contours as vector (polygon) layers. What I'd like to do is use the vector layer to estimate the population indicated from the raster ...
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2answers
603 views

Python, GDAL and building raster attribute tables

I have an integer raster for which I would like to build a raster attribute table using Python and GDAL. I can create a GDAL raster attribute table in Python as follows: >>> rat = ...
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0answers
24 views

Where can I find the 1-band color raster plugin for QGIS? [duplicate]

Possible Duplicate: How to install “1-band color raster color table”? I'm searching for the 1-band color raster plugin. What is the essential repository? Or is there another tool for ...
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1answer
121 views

extract data from several images to different shapefile columns using GRASS

I am now working in grass and I want to extract raster values from several images to a shapefile. I have already created the columns in the .shp where the raster values will be stored but I am facing ...
8
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4answers
2k views

How to modify single Pixel values in QGIS?

I would like to modify a raster (pixel values) in QGIS. The plugins "value tools" can easily provided me with the value of the pixel of my raster. However I know know how to modify it. I have found ...
2
votes
1answer
261 views

QGIS & GeoTIFF clipping Error “-srcwin 5897 137 0 0 falls outside raster size of 11083x4158 or is otherwise illegal.”

I'm trying to clip a GeoTIFF file and unfortunately I'm getting the following Error "-srcwin 5897 137 0 0 falls outside raster size of 11083x4158 or is otherwise illegal." From another post ...
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2answers
442 views

How to surround a clipped raster with transparency? (gdalwarp)

I am trying to perform the following task, but it does not seem to work: I have got a raster file (raster.tif) containing an aerial photo, which I want to clip using a Shape file (clip.shp) that ...
7
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2answers
279 views

How to remove long linear strips from polygons?

I have a polygon layer representing impervious land cover. This was taken from a land cover raster dataset. The impervious data represents all impervious surface that is not buildings or roads. I ...
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1answer
63 views

What units are used in GRASS Rasterize?

What units are used in GDAL Proximity or GRASS Rasterize? - 'new size' parameter
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0answers
240 views

Error when trying to import a raster file into a geodatabase

I am using ArcGIS 9.3.1. For some time I have had no problem importing a raster file into my geodatabase. That's recently changed and I have absolutely no idea why. Every time I try to import a raster ...
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3answers
12k views

Extract Raster Value into Polygon Attribute

I have Raster Data for a State which has Elevation Data in its pixels. I also have Vector layer which has the 300 divisions of State. what I need is, I want to get the average elevation value of ...
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2answers
331 views

How to produce a mean raster file based on other raster files? [duplicate]

Possible Duplicate: Tools to flatten the jp2 to a single band (average the bands)? I have a number of raster files from a same area, that coordinates of corresponding pixels perfectly match ...
3
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1answer
356 views

Problem editing raster and saving with projection and transformation intact

I am trying to make a custom tool to Arcmap using Python. It is supposed to read in a raster DEM, a point shape file and a distance, and output another raster. The output raster should be ...
8
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3answers
924 views

calculate area of vegetations in a raster file

How do I calculate area of several vegetation types in a raster (.img file type) image. They are color coded. Am using QGIS (1.8.0) and ERDAS 9.2.
3
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1answer
294 views

Stitching thousand of 32 bit Tiff without geographic information

I'm working on a project which goes beyond my knowledges, I need your help. I'm working with FLIR movies (thermal imagery recorded from plane), and I have to find a way to make a Tiff containing the ...
8
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3answers
2k views

Using polygons to apply unique value to all raster cells within those polygons?

In ArcGIS 9.3, I have a raster file that I would like to "mask" with polygons, giving a single value to all the raster cells that overlap the polygons. How can I do this? Here's a screen shot, ...
5
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1answer
339 views

How can I create a pollutant dispersion raster in QGIS?

As my previous questions have indicated, I am working on an air quality problem where I have a dataset of industrial emissions that consists of a location (long, lat), and an annual volume of ...
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3answers
943 views

Zonal Statistics as table creates output but some are Null

Here is my newest issue: I have temperature as a raster file and different ecoregions of a province as polygons. What I want to do is calculate the mean temperature per ecoregion. I succeeded in ...
2
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2answers
1k views

QGIS - extract raster values greater than 0

How can I extract values > 0 from an overall raster? I have a water level grid and a DTM from which I've derived flood depths (using the raster calculator) but obviously the final result contains ...
2
votes
1answer
341 views

how to load a raster into the Map Canvas using QGIS Action

Is it possible to write an Action in QGIS that will load a raster into the current map canvas based on a url/path of the raster as specificed in the attribute table of a shape file? The shape-file is ...
2
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1answer
395 views

Querying PostGIS Raster with MultiPoint

For one of my projects using PostGIS 2 I have a table with GPS tracks (igc_files). It holds records including a MULTIPOINT() column that has about 1,000 points for each record and a column that has an ...
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2answers
382 views

In ArcGIS 9.3, how do I eliminate the slivers of missing data between polygons?

I am editing a single-band .tiff file in ArcGIS 9.3. I started with an image that I had to georeference, but unfortunately, the image had these little slivers of missing data between the data cells. ...
3
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2answers
3k views

Polygon to Raster Tool Problem

I am trying to create a raster data set from county level polygon data for the US. I have successfully created one raster from a dataset, but when attempting another, it does not work. I am ...
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1answer
2k views

In ArcGIS 9.3, how do I split a 3-band raster (.tiff) file and summarize the band values?

Using ArcGIS 9.3, I would like to make a new, single-band raster file that includes only one value: a summary of the three existing bands. The composite band is currently a composite .tiff file. ...
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vote
1answer
183 views

Why is transparancy of GRASS rasters missing when imported into QGIS?

I have a raster map in QGIS imported from a GRASS mapset with the QGIS GRASS plugin. The problem is that I have null() cells in the GRASS map that appear "colored" in QGIS. How can I set the ...
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vote
1answer
64 views

How to conflate terrain data?

I have an 8 km by 8 km raster of 20 m/pixel terrain data. The georeference data has been lost. All I know is that it's within 100 km of Smithers, BC. I realize that this might involve some very heavy ...
2
votes
1answer
209 views

how to create an outline polygon (footprint) from raster data with postgis?

how can I create a polygon, containing the actual outlines (aka footprint) of a raster file with postgis? I just need the outlines of the data containing parts of the raster. ST_PixelAsPolygon ...
8
votes
1answer
1k views

How to make a new raster using con() script in Python?

I'm new to Python and have been trying to code a raster calculator style script. Basically, I want to convert a raster that has values 0 to -10,000 into a raster that is populated by 1s between ...
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vote
1answer
176 views

Clipping Rasters with a mask layer error

I've got a NDVI layer that I'm trying to clip with a vector file but when I try and use GDAL Tools clipper I get an error. That shows up like this: What am I doing wrong? This is before I even pick ...
2
votes
1answer
645 views

Orux Maps raster display

Does anyone know what format of raster images works with Orux Maps? I tried to export maps acc to Orux Maps specs from ArcGIS 10.1 in every possible format (Geotiff, GRID, jpeg2000...), loaded with a ...
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4answers
1k views

Attempting to bring 2,300 .sid files into one raster

I've tried all of the raster tools within ArcToolbox with no luck having such a large number of files. There are about 7GBs worth of MrSID files totaling about 2,300. Most tools fail or process too ...
4
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1answer
480 views

How to convert a JPEG to GeoTiff using FME?

I want to convert JPEG to Geotiff in FME. I use the following workspace JPEG reader -> RasterExtractor -> CoordinateSystemSetter -> RasterGeoreferencer (parameter : extents) -> Reprojector -> ...
5
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1answer
623 views

Can QGIS handle .adf attribute data?

I have been using QGIS for about 4 months now and its been great to learn a new package. I have been trying to open a source raster (*.adf) files in QGIS. I can display the raster set itself, ...
8
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1answer
2k views

How to reproject a raster file in QGIS with datum transformation?

I want to reproject a tiff raster file from projection A (ETRS89/UTM Zone 32) to projection B (DHDN/Gauss-Kruger zone 2). The two projections have a different datum so I have to use a datum ...
2
votes
2answers
362 views

How to get easting & northing of cell in raster using ArcPy?

It might be very simple task. But I would appreciate if someone can comment on How I can get easting and northing of a single cell raster using arcpy as this value is used for in further steps. ...