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

learn more… | top users | synonyms

2
votes
1answer
103 views

Symbology Stretch Multiple Raster

I need to change stretch of a raster using properties - Symbology to Minimum-Maximum like image bellow : Problem is I have about 172 raster, is there any way to make this automaticaly change? I ...
0
votes
1answer
95 views

Will a WMS handle RPF image scale?

When serving RPF imagery (Raster Product Format) from a WMS, will the WMS handle which layer should be on top? For example, let's say I request layer X and layer Y in some bounding box, and layer X ...
0
votes
1answer
34 views

r.series command in QGIS - timeseries

I am using r.series command in qgis. The command is performing correctly, but when I import input raster files, it creates a list in a random order. Sometimes the order of input rasters is essential ...
8
votes
3answers
3k 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, ...
0
votes
1answer
270 views

Clipping Rasters from Mosaic Dataset in their Original Coordinate System

I am building a large mosaic dataset that contains several hundred rasters, which are spread across three UTM zones. My goal is to be build a tool in ArcMap (most likely within model builder) that ...
1
vote
1answer
77 views

How do I replace cell values of a raster using values of another raster with differing extent?

I have two rasters (raster1 and raster2). The raster1 extent is smaller than raster2. I want to replace the value of raster2 pixels using raster1 pixels. How can I replace the values?
-1
votes
2answers
121 views

Counting raster points within boundaries in another layer?

I know this question is similar to some out there, but I have tried all the 'solutions' and none of them are working for me. I am using the latest version of Qgis. I have a raster layer with ...
-1
votes
1answer
27 views

Setting Pixels Band Values

I have a single band RASTER of an area, in which I want to create 360 bands and then assign those bands values from a table. Is there a process for doing this?
0
votes
0answers
41 views

Rasterizing vector contour data: Python error message

would anyone know why qgis kicks up this error message (image attached) when using v.to.rast.attribute? the rasterise related to a contour set. i duplicated it twice to create 3 copies. the first ...
0
votes
0answers
100 views

Arcpy raster calculation producing random no data cell in output

I've been trying to get the raster calculation below to work using python: import arcpy from arcpy import env import os from arcpy.sa import * arcpy.CheckOutExtension("spatial") KSat_mm = ...
2
votes
1answer
124 views

How to batch generate thumbnails of raster layers with R?

I have been using R to maintain a rather large stack of raster layers (over 700 layers of data for sub-Saharan Africa). Each layer looks as follows ...
0
votes
1answer
45 views

How to select a specific area (in a polygon form) determined by some value range in a raster band?

For example, I want create a vector layer with polygons that represents all areas where the elevation is between 500 and 600. Someone has any idea to help me? I'm using PyQgis 2.2.
0
votes
1answer
83 views

QGis export part of map (box with coordinates) as raster

I would like to export a map of Switzerland (as part of googlemaps) to use as a background for a graph, but I need to know exactly where each corner of the map corresponds to (wrt spatial ...
2
votes
2answers
393 views

Calculate Slope Between Pixels Through Time: A Time Series Trend Analysis

I have a 9 year weekly time series (~500 raster grids of equal cell size and extent). I'm interested in obtaining the regression line slope between pixels (Imagine stacking all 500 grids on top of ...
3
votes
1answer
77 views

Export Stretch Function values - Arcpy

I'm looking for a way to export Stretch Function values from images that’s stored in a Mosaic dataset. Not values from the whole set, but specific stretch functions per image. The set is stored in ...
0
votes
0answers
52 views

Disable option in QGIS which picks 4th band as alpha band

Is there a way to disable that function? As somebody who works with 4 band orthoimagery on a daily basis, it is annoying to go to the transparency options every time I load an image to disable the ...
0
votes
0answers
41 views

Slope regions from elevation points using QGIS 2.0

I am using QGIS to create a layer of slope region polygons (e.g. less than 30% slope, 30-50%, more than 50% categories). My data comes from point elevations and I interpolated using SAGA b-spline ...
0
votes
1answer
92 views

DN value from raster to vector tool (QGIS 2.0)

I am using QGIS 2.0 to convert a DEM to vectors, then create polygons of zones of slopes. However, I am unsure of in what units my new "DN" column is. It has lost of precision of z-values from my ...
11
votes
5answers
9k views

How to perform Raster Reclassification in QGIS?

Is there a way to do reclassify a raster image to Qgis? In Arcgis you can do that in Spatial analyst Tools→Reclass→Reclassify Any ideas?
2
votes
0answers
56 views

Is it feasible to reclassify a raster which has been resampled/smoothed for display purposes?

Background: I have a Google Earth KMZ file which shows ground movements after an earthquake, arranged into discrete classes: From the KMZ file I'm able to download the original PNG images, which ...
1
vote
0answers
49 views

rasterize a geography polygon using postgis 2.1

I am still bit new to Postgis 2.1. I am trying to rasterize a polygon, meaning that I have a polygon of Syria and I want to create an empty raster that contains the shape and geography reference of ...
0
votes
0answers
98 views

Issues creating slope raster layer from a point layer

I'm trying to create a slope raster layer using QGIS 2.0 on Windows XP. I started with a points layer with the Z elevation attribute. I then used the interpolation plugin to create a DEM. But, ...
2
votes
2answers
328 views

Nested loops for raster calculation arcpy

I am trying to figure out a way to input corresponding raster datasets from two separate folders into an equation using arcpy. I think it requires some sort of nested loop but I can't figure out how ...
1
vote
2answers
482 views

Replacing raster values in one raster with another raster in QGIS … how to?

I have a raster (DEM) and want to replace a few cell's values with the values from another raster in QGIS. I would have done this with the "over" tool in the raster calculator in ArcGIS. Specifics: ...
1
vote
1answer
88 views

Need to calculate values for a cell based on surrounding landscape

I have a raster file with the urban development of a county mapped out (values: 1=urban 0=not urban). I also have a raster file with several blocks of forested land, each block of land has its own ...
0
votes
1answer
70 views

Passing RasterDataSource object to RasterData object in Javascript API?

I have a GP service that requires a RasterData object as input. The RasterData object should hold a RasterDataSource object, but I'm not sure of the syntax to connect these two classes. The API ...
0
votes
0answers
66 views

How to get RasterToPolygon working

We have a process that is almost working except for this one call ... This is the one tool function that is requiring a FeatureClass and I found code that I thought would work. Unfortunately all I ...
1
vote
1answer
315 views

Raster calculation in for loop returning exit code -1

I've put together a python script that does some calculations on rasters by converting them to NumPy arrays, doing the math, then converting them back to Raster and applying all the same spatial ...
0
votes
0answers
60 views

How to draw rotated symbol RASTER type layer in Mapserver?

[PARTIALLY SOLVED]: I was on the wrong track I need to use a UVRASTER, see this part of the docs But doing leaves with with another question about how to get the angle correctly, please see this ...
1
vote
0answers
47 views

MapServer: UV_ANGLE not calculated correctly?

I'm following this example given on the MapServer website. But the angle of the raster is incorrect: The data is my grib files is correct, and should not yield these perfect opposite directions. ...
0
votes
1answer
279 views

Iterative raster calculation script using NumPy arrays breaks after ~10 rasters, returns: “TypeError: Cannot create raster for numpy array.”

Here is my code: #Generate Cumulative Thresholds #5/15/14 import os import glob import arcpy import numpy as np #Enable overwriting output data arcpy.env.overwriteOutput = True ...
0
votes
2answers
543 views

Change detection with raster calculator

After applying the Diff operator of the raster calculator in arcgis to view changes in land use, would like to see the areas of increased and areas of decreased. This is possible using the raster ...
0
votes
1answer
21 views

upload data to geoserver with gxp upload panel

I installed geoserver in my computer. I use wampserver (php, apache), and when i use the examble "layer-upload.html" then i have the erro 405: Failed to load resource: the server responded with a ...
0
votes
1answer
173 views

How wrap GRIB data in Mapserver 6.4

I'm trying to draw a combination of layers with Mapserver. One of the layer takes a shapefile as input and the other one is based on GRIB data. The issue is that the GRIB layer (in green) is drawn ...
1
vote
0answers
61 views

PostGIS raster connection is not closed by MapServer

I'm using PostGIS raster in MapServer like this: TYPE RASTER DATA "PG:port=6432 dbname='mydb' user='postgres' password='1234' schema='public' table='truemarble' mode='2'" PROCESSING ...
2
votes
1answer
47 views

Identifying X-Y coordinates from a raster

I need to find the high and low values of multiple raster datasets individually. Then determine the x,y location of these values. I am using ArcGIS 10.1, have built the mosaic datasets I need, and ...
0
votes
0answers
33 views

R equivalent of GRASS r.grow?

What is a good R equivalent of the GRASS function r.grow? The closest I've been able to find is the script suggested by whuber in response to Creating randomly shaped clumps of cells in a raster from ...
0
votes
1answer
96 views

Multiply point values by raster values

I have a point shapefile containing elevation values in the id field. The shapefile is overlaying a raster layer of the topographical slope. Is it possible to multiply the elevation value of each ...
1
vote
1answer
42 views

Improve display of fine resolution raster

In the above map, I am showing yields on some parts in Iowa at a pixel resolution of 100m. However, in this case due to the relatively small number of pixels (and high resolution), the map is not ...
4
votes
2answers
174 views

How to query DEM elevation values in a web application based on cursor/click point location?

I work for a city government that has LiDAR derived DEM rasters which we would like to make accessible to other departments in the city. The problem is that many departments don't have anyone with ...
0
votes
1answer
92 views

json issue: GetFeatureInfo with raster images

I have succesfully typed a GetFeatureInfo request with the following structure directly into my browser: ...
1
vote
1answer
493 views

Is there a way to remove this thick gray border from my raster symbology in the legend?

I have this problem with different raster layers, in this instance it's land use data. In my layout, and in a rendered PDF of my map, the legend entry for the raster layer has an ugly, thick gray ...
0
votes
1answer
114 views

How do I convert coordinates to raster (bsq, bil) lookup?

I have a .bil file, which has interleave = bsq in the hdr file. I'm having trouble finding any insight into how I would essentially do a lookup on the file. I have no problem reading a specific ...
0
votes
1answer
54 views

Is there an easy way to refresh / update a raster tif file in GIS?

Apologies for the newbie / basic question, but it seems to be a fairly simple concept which I can't get to work properly, and I'd be really grateful for a pointer or two! I have a load of different ...
0
votes
1answer
163 views

Setting a value on a raster where a polygon intersects cells

I reviewed all of the supposed 'answers' and I just do not see that they really answer my question. Mostly because the ones I'm reading are setting values either inside or outside a boundary. So let ...
0
votes
1answer
61 views

Unable to get processing extent to match desired raster output

I have a few thousand ortho mosaic tiles that I've resampled to a lower GSD and am trying to cut into larger tiles. I developed a script that has worked perfectly for thousands and thousands of tiles ...
1
vote
0answers
51 views

Import raster to postgis and add a foreign key constraint

I use raster2pgsql to import raster files into a table with this command line: C:\Program Files\PostgreSQL\9.3\bin>raster2pgsql -s 4326 -M -F -a c:\temp\mun.tif public.basqui_raster | psql -U ...
5
votes
2answers
1k views

Rasterize a vector layer in PostGIS

Related to this question asked here on gis.se and this thread on postgis-user, has anyone worked out a good solution for in-database rasterization of a vector layer using PostGIS? It sounds like the ...
1
vote
1answer
360 views

How to export a Raster attribute table into a .txt using Model Builder

I'm using ArcGIS 10.1 I need to export a Raster attribute table into a .txt (or any other format Excel can import), using Model Builder. Is it possible?
2
votes
1answer
41 views

Setting Point Cloud Data Colour from Raster

I was reading this article: http://blog.safe.com/2013/10/14-ways-to-take-charge-of-lidar-data/ Number 12 states that you can change the colour of your point-cloud data by using a raster image. Does ...