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

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167 views

Coordinate system of a raster file to be introduced for transformation

I am working on raster data using GDAL. When I extract coordinate system information of the files I got this: PROJCS["Geostationary_Satellite", GEOGCS["GCS_Unknown datum based upon the custom ...
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1answer
146 views

How to correlate raster map and elevation data?

I have been provided with a set of raster maps. Thanks to another helpful user here I have been able to acquire some elevation data for the same region from gis.utah.gov in asc format. Now I need to ...
3
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1answer
93 views

GRASS r.grow doesn't seem to change raster values at all

I have a raster map in GRASS that looks like this: The red cells have a value of 1, the yellow cells have a value of 0. I am trying to use the r.grow command to 'fill in' the gaps in the red ...
4
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2answers
899 views

Annoying little line in color ramp legends - how do I remove it?

This was never a problem with ArcGIS 9 but it appears that in 10.0 Esri has added small horizontal lines as the default when including color ramps in legends. I want to get rid of these annoying ...
4
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5answers
753 views

Python loop Polygon to raster not working

I want to convert a large number of different shp polygons to raster in ArcGIS 10.1, using an existing field column "class" for the new raster classes. I am not very fluent in python but I thought ...
3
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2answers
674 views

set geotiff 0 values to nodata

Is there a way to set all the 0 value pixels on a raster to nodata using gdal or qgis?I world like to use fillnodata to fill some holes, but holes are set to 0,so I need to delete them first
3
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1answer
2k views

Creating Isolines from point Data

I'm quite new with ArcGis 10 so I’m having difficulties with something that may be simple to some. Anyway I have a list of bores that I’ve plotted using coordinates. Now I need to draw a single ...
4
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2answers
372 views

Find locations of raster maximum within polygons: Basin Delineation

I'm trying to identify the Location (lat/lon) and upstream area of every raster point that flows into the Arctic Ocean (there are a lot so it has to be fully automated). I'm starting with the ...
4
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2answers
952 views

How to get an extent for Raster using python

I have to get an extent of a given raster so that I can save it and use the same to clip another raster with that extracted extent. As of now I am stuck in the extent part. import arcpy from arcpy ...
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0answers
88 views

GRASS error reading raster map: request for row 1 is outside region [closed]

I'm a rather inexperienced GRASS user, and am trying to use an addon module called r.geomorphon (see http://sil.uc.edu/downloads.html#software). I've managed to get it installed and am trying to run ...
2
votes
1answer
113 views

From Raster to Masked and Filtered Polygon Vector

I have a set of rasters (geologic risk) from which I want to extract zones with a specific color, clipping them with a polygon (administrative borders), outputting a shapefile. I'm using QGis (and ...
2
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1answer
251 views

Raster Analysis - Identifying features from Raster

I have an IDW, tension spline and hill-shade rasters that show an archaeological landscape and from these rasters I want to identify new features which are seen in the landscape as depressions. And ...
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0answers
147 views

Sextante - SAGA- Shape to grid question?

I have a vektor shape (Index 1-5). After using the saga tool (shapes to grid) I'm getting a raster (values 1-5). The problem is that the NO DATA area is defined as 129. Is it possible to set 129 as no ...
3
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1answer
758 views

GeoTiff convert to PNG with transparency

I need to convert a GeoTIFF image to PNG format with "NoData" pixels in the original image being transparent in the output. Is there any tool particularly in ArcGIS ArcToolbox or GDAL for this ...
5
votes
2answers
275 views

How to modify raster pixel inside a polygon?

I would like to set to novalue all the pixels of my raster inside a polygon. I'm trying the gdalwarp command line with -cutline option. But this command extract the values of my raster inside the ...
4
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1answer
393 views

Recoloring geotiff for visual presentation

I have a rather big Geotiff. It is the mosaic of four RapidEye satellite images. They are all a bit bland/grayish. When combined I would like to freshen up their colors so that they are more visually ...
2
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1answer
542 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
218 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
767 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
622 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
votes
1answer
373 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
158 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 ...
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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
265 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
662 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 ...
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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
679 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 ...
1
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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 ...
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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
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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
446 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
284 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
241 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
334 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
votes
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
votes
3answers
931 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.
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1answer
296 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, ...
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1answer
347 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 ...
2
votes
3answers
952 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
votes
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 ...