Rasters are regular grids of values, usually stored in an image-like format.
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2answers
20 views
how to decrease Raster size without altering cell size?
Is there a way to decrease the size of a raster image without decreasing cell size or quality?
I´m using ArcInfo but also have Saga-Gis or FME.
I could abviously change an 8bit raster to a 1bit ...
0
votes
1answer
29 views
How to create attribute table for raster data?
I have raster dataset for rainfall but its not having attribute table.
How can I create tabular data using the same raster file? How to join it back again to it?
Software used is ArcMap 10.1.
2
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0answers
14 views
Arcpy.GetRasterProperties_management values do not match values found via ArcCatalog
I am using Arcpy to extract the mean and standard deviation values of tiff Landsat satellite images and I get very high values. Values in the thousands rather than in the low hundreds! If I look at ...
1
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0answers
4 views
How to Iterate ModelBuilder for Zonal Statistics?
I want to use ModelBuilder to split a DEM into multiple tiles, then run the iterator on each tile made for the Zonal Statistics tool to find the highest point(s) in each tile and give these as an ...
0
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3answers
59 views
Grouping Multiple Raster Layers
My question is how to create multiple raster layers group, for example when using several aerial photos. I wish to group the layers into one so that I can edit/select as a batch rather than having to ...
0
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0answers
19 views
ArcGIS10 Highest point via polygon features
I am using ArcGIS 10.0 with 3D Analyst, Spatial Analyst and Military Analyst.
I feel like I am halfway to solving a problem but do not seem able to completely solve it.
I have a polygon shapefile ...
2
votes
1answer
52 views
Convert multiple Shapefiles in Raster in R(and then plot it)
I'm trying to convert several shapefiles in rasters at the same time. I already was able to read the shapefiles by doing this:
library(maptools)
shps <- dir(getwd(), "*.shp")
for (shp in shps) ...
0
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0answers
36 views
How to reclassify a raster (tiff) with multiple bands?
i have a raster file containing information about the windspeed average for the year. My purpose is to reclassify the 15 classes based on their rgb-composite. The color is the only information given. ...
0
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1answer
21 views
ArcMap Raster to NetCDF - lat/long
I need to convert a few files which are projected in WGS84 into netCDF. NetCDF requires lat/long. I am a bit confused on how the process is handled by ArcMap especially after looking at the online ...
1
vote
1answer
63 views
Why does georeferencing reduce the image resultion?
I'm trying to use a raster as a base image in my QGIS project. It is a building schematic which is fairly high resolution. Importing this into QGIS, it seems that the only way to re-position an ...
1
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1answer
27 views
Needed a free high resolution imagery for Las Cruces, New Mexico area
I'm Looking for a free download Imagery that is a very high resolution and the most recently like the past 3 months.
I'm doing to produce a map where our new building being move into next year ? Is ...
1
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0answers
53 views
Why are the colors of my WMS layer messed up in QGIS?
I have a raster image on my computer, and I used it to test some geoserver features. (I'll upload images to show you what the problem looks like)
I have the same raster, but transferred by wms. And ...
2
votes
2answers
34 views
Most efficient option to create a raster basemap for a web application?
I'm sure this is probably a common problem and many have already found the right answer.
I have a large mosaic raster file (a city's ortophoto) in .ecw fromat and we want to use it as a basemap in a ...
0
votes
0answers
16 views
How to convert Raster to polygon in MapInfo?
I wanted to convert Raster data to point data in MapInfo.Does there any tool to convert? can anyone help me?
1
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1answer
36 views
Raster Data to Polygon [closed]
I need to "translate" raster information to a set of polygons.
The raster to polygon tool will not work.
I created a fishnet with the same resolution of the raster and converted it to polygons.
I now ...
1
vote
2answers
32 views
How to convert raster to point in QGIS
I wanted to convert Raster into Point Vector in QGIS. Is it possible? QGIS have option to convert it into polygon but i didn't found any tool to convert it into point. can anyone help me?
1
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0answers
21 views
How to Clip a Raster dataset so that it is smooth along a boundary [closed]
I know how to clip a raster, however I need it to be smooth along the edge of a boundary and not jagged as can be seen in the image.
0
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0answers
33 views
Interpolation Technique
We have following solar metro logy parameter through satellite data with resolution of 100 Km^2 (10Kmx10Km)
Insolation on horizontal surface
Diffuse radiation on horizontal surface
...
2
votes
1answer
41 views
Spatial Analysis - Calculate a cells elevation (height) above the nearest stream cell
I have searched for some ideas on how to formulate this analysis, but have come up short. I imagine there is a pretty straight forward answer; any help would be greatly appreciates.
Data:
DEM, ...
1
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0answers
21 views
Map algebra from QGIS python console? [duplicate]
What command do I use to do map algebra on rasters from the QGIS python console?
0
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0answers
16 views
Working with Raster Data in MS SQL [closed]
Does MS SQL supports Raster dataset and Raster analysis?
1
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1answer
19 views
Georeferenced labeling
I have a problem with ArcMap that somehow affect georeferencing.
So I have three layers, two with .lyr and one is a raster data.
The two .lyr datatypes are a border and cities with names. I ...
1
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0answers
25 views
What type of calculations must be done for traffic emission for buffers in land use regression?
I have a raster layer that shows traffic emission distribution by kernel density method. Traffic emission will be used as independent variable in land use regression.
What type of calculations must ...
1
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1answer
50 views
If road lengths are raster layer, how to calculate road lengths for different buffers?
A question related calculation of road layer lenghts usign raster layer for land use regression.
If raster layers are used instead of vector layer for calculation of land use area and road lengths, ...
0
votes
0answers
47 views
What types of buffers (donut or overlapping) should be used for land use area and road length calculations in land use regression? [closed]
What types of buffers (donut or overlapping buffers) should be used for land use area and road length calculations in land use regression? (Output of buffer analysis will be inputs to a statistical ...
0
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0answers
31 views
Methods to calculate Viewshed analysis
Does anyone know an algorithm to calculate Viewshed analysis?
I calculated them in ArcGIS, MapInfo and SAGA GIS.
I wish to calculate Viewshed analysis using algorithm or methods which I can use in ...
2
votes
1answer
21 views
How to change layer transparency without changing border lines?
I have a raster image of elevations. I have added a vector shapefile that contains local political divisions. I want to keep the elevation colors, but I want to keep the black lines representing the ...
0
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0answers
47 views
Viewshed calculation using SQL
Can i calculate viewshed in MS-SQL server? Viewshed analysis is Raster operation. I have elevation value vector observation as point vectors. Are there any methods to calculate Viewshed (using ...
0
votes
0answers
16 views
Transformation type - when to use which type? [duplicate]
I am using QGIS 2.0.1 on a Mac, and I am georeferencing a scanned map from 1822. The image is an excellent quality scan, and includes a grid of lat-long. I do not know much else about the map that ...
0
votes
2answers
35 views
Clipping polygon layer into multiple polygons via model builder?
I have a huge polygon layer created from a raster, and over that I have a watershed shapefile. I need to run a land-use regression process on each individual watershed so I'd like to clip and export ...
0
votes
1answer
20 views
How to add raster data to Table of Contents using python?
I can easily add shapefiles to the Table of Contents in Arcmap using the following codes:
mxd = arcpy.mapping.MapDocument("current")
df = arcpy.mapping.ListDataFrames(mxd, "Layers")[0]
path = ...
0
votes
0answers
10 views
NPP value convertion [closed]
How can I convert the value of NPP on an image into unit of PgC/m2/month. NPP values on single monthly image is ranging from 25 to 260 and the pixel size of the image is 250x250m. Do I need to take ...
1
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3answers
80 views
Is it possible to open rasters as array in NumPy without using another library?
I know that it is possible to open a raster as an array in NumPy using GDAL, but I want to skip GDAL and use NumPy only, as it is cooler handling rasters with NumPy as matrices.
There is a similar ...
0
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0answers
38 views
using arcpy in python, having trouble with manipulating rasters [closed]
In this script I am retreiving a list of data sources from mxds in a directory.
I want to copy all of the data to a new location (except if it is over a certain size).
I ran into the issue of some ...
1
vote
1answer
38 views
Load Raster Values into Shapefile [duplicate]
I have a shapefile containing many points.
Some of these points fall within an area for which I have raster data.
I would like to load the values of the raster which underlie each point into the ...
3
votes
3answers
55 views
How to show cell boundaries on a raster?
I am trying to recreate a situation where each cell from a raster dataset has a black border as seen in this image. Any ideas?
1
vote
1answer
33 views
Re-sizing Raster file pixels
I have 2 JP2 aerial imagery files that are incorrectly sized. They are 100x larger than the other aerial images but correctly geo-referenced (starting x, y co-ordinates).
I believe the issue is their ...
1
vote
0answers
25 views
Image classification for a study site falling over two adjacent Landsat 8 scenes (qGIS or ArcGIS)
This question concerns work-flow rather than specific methodological problems.
I will be using GRASS to classify Landsat 8 images to create a vegetation map for a study site that happens to fall over ...
0
votes
1answer
38 views
How to get custom color palette in rasterVis plot3D in R?
I am trying to insert an RColorBrewer palette to visualize an elevation raster in R using the rasterVis function plot3D. The rasterVis reference document shows the following parameters:
plot3D(x, ...
0
votes
1answer
39 views
How to Iterate through Bands of Raster using ArcGIS 10.1 ModelBuilder?
I have a large number of rasters with 3 bands (R,G,B). What I want to do is add all 3 bands of each raster together to end up with a single band image with the summed R,G,B values in each pixel but ...
2
votes
1answer
46 views
Raster layer calculator
In PCI Geomatic, I have two raster layer.raster1 identified like %1 and raster2 like %2.
if (%1 <= 10) then
%2 = 60
elseif (%1 > 10 and %1 <=50) then
%2=80
elseif (%1 > 50 and %1 ...
0
votes
0answers
42 views
Touch up tool for rasters?
I was wondering if it were at all possible to manipulate/massage rasters (eg Geotiff) using Qgis plugins or Grass??
By manipulate, I mean manually smooth off interpolation artefacts, blended surface ...
1
vote
0answers
52 views
Why does CON statement give ERROR 010240: Could not save raster dataset to (value) with output format GRID?
I am receiving the following error when trying to run the following code:
import arcpy
from arcpy import env
from arcpy.sa import *
arcpy.CheckOutExtension = "Spatial"
env.workspace = ...
2
votes
1answer
47 views
ArcPy findAndReplaceWorkspacePath not working with Raster Datasets
Situation:
I am working on creating a Python script that will replace workspace paths for every layer in a map document in order to fix broken layers after a data migration. The script works except ...
1
vote
1answer
37 views
“dataset does not exist or is not supported” using large GRID raster
I am trying my hand at arcpy for the first time to create a conditional raster from a set of threshold values. I have 3 large GRID format rasters (mos_zb3, mos_zb4, pca_finb2) I am trying to feed into ...
0
votes
1answer
19 views
QGIS proximity raster with extent beyond original coverage?
I need a raster coverage of distances from points outside the geographic region of interest, and am having trouble doing this with QGIS.
Questions like this one (Calculating distance to points in ...
0
votes
3answers
28 views
Grass GIS 6.4.3, How to create a .PTS file
I'm trying to export a raster map in order to use it in the Flo-2d program.
This program needs a .pts dtm file, do you know how I can create it?
Alternatively, I can use a xyz file looking like this ...
1
vote
0answers
82 views
Loading PostGIS raster layer into QGIS
I am unable to load a PostGIS raster layer into QGIS. I have looked through previous posts Loading raster from PostGIS DB into QGIS
and Cannot add the PostGIS raster layer with QGIS but was not able ...
2
votes
0answers
28 views
Wrong pixel sums within buffers in Esri ArcGIS 10.0
I have a raster of Zambia, 100m² resolution (about 650mb). Buffers (single) at 1,2,3,4,5,10,15,20,25,30,50 km.
I'm running "zonal statistics as table" in the model builder for all buffers (actually, ...
1
vote
0answers
37 views
Saga Reclassify grid problem
I am using Qgis 2.1 ver. 5f5cd4c (64 bit version on win7 64) OSGeo installed. I was trying to reclassify a DEM in EPSG:32614. I used the SAGA's Reclassify algorithm in the processing toolbox. I ...
