To alter the frequency of sampled data points in continuous data.

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1
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2answers
55 views

Divide two rasters with different cell sizes using ArcGIS for Desktop?

I've got two rasters of the exact same location (So every pixel in one raster is equivalent to the pixel in the other raster). Raster A has a resolution of 6m per pixel. Raster B has a resolution of ...
3
votes
2answers
78 views

How can I smooth or resample a DEM to find steep roads?

I am trying to find sections of road with steep gradients. My process is: pull a linestring from Openstreetmap data resample it to create a point every 10 metres look up the height data for each ...
0
votes
2answers
34 views

Convert Raster Resolution in arcGIS

I have to analyze 8 raster layers, 5 of them are 0.5 degree resolution and the other three are 0.05 degree resolution. Firstly, should I resample the 5 to finer resolution (0.05 degree) and if ...
6
votes
1answer
68 views

What resampling technique should be used to reproject an altitude raster?

Does anyone know whether I should choose: nearest, bilinear, cubic or majority when projecting the WorldClim altitude raster layer?
2
votes
1answer
77 views

Gdal/QGIS resampling asc file

I have a DEM (.asc) file with a resolution of 1000 meters per pixel. Therefore the file has a lot of columns and rows. I would like to chance the resolution per pixel from 1000 to 3000 meters per ...
3
votes
1answer
36 views

1m cell size equivalent value in decimal degree

I'm doing re-sampling pixel size in ERDAS 2014,I'm using input image(Indian terrain) in GCS_WGS_84 projection. Now I have to keep out put cell size as 1m,what is the 1m equvivalent value in Decimal ...
1
vote
1answer
17 views

The resampled image has many NaN values and does not cover the complete area of the input raster

when I resample an image of 20m to 240m resolution, the resampled image does not cover the whole area of the input image and does the resampling for some pixels in which I get many NaN values. How can ...
3
votes
1answer
63 views

Is the bilinear resampling technique appropriate for the projection of ASTER data?

I need to project some ASTER data from a geographic coordinate system to a projected one. I have read online that the cubic resampling technique is the most appropriate for this purpose. However, ...
1
vote
1answer
50 views

Better way to combine 2 rasters

I have two raster layers: One with 56 m resolution and the other has 30 m resolution. Usually, I just use the 'Combine' command in ArcGIS to combine them, getting a single value for each unique ...
2
votes
0answers
45 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 ...
1
vote
1answer
45 views

Resampling with Python console (QGIS): number of parameters

I am trying to resample two raster layers with Python console in QGIS with this code: outputs_0=Processing.runAlgorithm("saga:resampling", ...
0
votes
1answer
97 views

Best Resampling Method for DEM reprojection in QGis

I need to reproject a DEM (aster file) in order to have the same CRS as all my other project data - I have different SHP for the same DEM's location but they have a different CRS. Which resampling ...
0
votes
2answers
89 views

Is it permissible to redefine raster resolution (not resample!) in order that it be included in a SDM?

I'm fitting a SDM using R. A requirement is that all environmental predictor layers have the same extent, origin and resolution. I have high resolution bathymetry data (25m) that I will resample to ...
2
votes
0answers
46 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 ...
9
votes
1answer
253 views

When dealing with rasters of varying resolutions should one resample to the highest or lowest resolution?

I'm looking for recommendations on best practices for dealing with raster data layers with different resolutions and projections. The advice I've been given is to always resample to the layer with the ...
1
vote
2answers
108 views

How to resample polygon vertices so that they are evenly spaced in Arc 10

I have digitized the outline of many river channels (by both manually picking points and using streaming mode), but now I need the vertices to be evenly spaced (for input to another program). I tried ...
2
votes
1answer
1k views

How to resample GeoTIFF images to the same resolution?

I have two geotiff images that I would like to resample the same resolution. If I use ArcGIS this would be easy to do. But using QGIS I don't know how to do this. Some help will be very appreciate. ...
3
votes
0answers
116 views

Can extracting raster values work in polygons' CRS without raster resampling?

I am trying to extract raster values using polygon layer with different CRS. Raster is in WGS84 (EPSG:4326) and the polygons in UTM (EPSG:23031). 1. If I want to work in the projection of the ...
2
votes
1answer
159 views

Lack of Options in Gdal Tool “Build Overviews” QGis

I am using QGis 1.8 and I want to build overviews (pyramids) for satellite imagery using the Gdal Tool. I would like to use the resampling method "cubic convolution", but the option doesn't exist ...
3
votes
2answers
623 views

Resample, ArcGIS: How do I avoid resample taking into acount NoData values?

I am trying to Resample a raster dataset to match the resolution of another dataset. I have fine resolution data on small islands (surrounded by NoData in the sea). When I re-sample the data to a ...
2
votes
1answer
145 views

Is GeoServer Image Pyramid upscaling?

I have an Image Pyramid in GeoServer 2.2 RC3 (not the latests - I know, but I have other pyramids working here). The total size is around 1TB and file size is around 1-2GB for each GeoTIFF. When ...
3
votes
1answer
125 views

Differences in raster extents in gdalinfo, SAGA & Quantum after resampling

I recently resampled a raster file using SAGA's Resampling module. The aim was to widen the extent of the new raster to two decimal places, where the original raster has three decimal places. The ...
0
votes
0answers
790 views

How to resample a raster in QGIS?

I've got a boundary file that I would like to resample the raster file from a 30m grid to a 10m grid inside the boundary file. When I try and do it in Qgis or Grass all I get is one big raster cube ...
3
votes
1answer
340 views

Vector to Raster for Smoothing purposes

I have a vector file that represents transit scores by CT of a city. It shows harsh boundaries where one CT has great access to transit and right beside that CT is one that has extremely poor access. ...
4
votes
1answer
91 views

What proportion of the 240m area sensed by MODIS must be forest before it is defined as forest?

MOD12 is a MODIS product at 240m resolution. Landsat produces 30m resolution products, which I resampled to 240m resulting in a raster of proportion forest cover in each 240m pixel (based on the mean ...
3
votes
1answer
192 views

how to square the pixels of a GeoTiff

I have a GeoTiff that has been supplied to me with non square pixels (I suspect due to reprojection to lat lon at some point). However the next step in my processing chain requires a Arc ASCII grid as ...
8
votes
2answers
828 views

Resample binary raster to give *proportion* within new cell window

I would like to go from a binary raster of forest/non-forest at 30m resolution to a raster at 240m resolution with the value of each cell being the proportion of that cell forested - i.e. the data ...
2
votes
1answer
266 views

Raster format with rotated cells - no resampling

Is there any way to rotate a raster w/o resampling? I am aware that rasters are always 90 deg perpendicular grids, but is there any file format or methodology that allows for a diagonal raster - one ...
5
votes
1answer
542 views

Change the image size in ARCGIS

I did interpolation operation on temperature and precipitation data. Output image size is 3300 (col) and 2550 (row). I have some NDVI images with size of 15456 (col) and 5074 (row). Generally, I want ...
16
votes
2answers
2k views

What resampling technique should be used when projecting aerial photos?

I'm doing some time-intensive projecting of aerial photos, and I'm curious - what resampling technique is best to use on aerial photos? In ArcMap, my options are NEAREST, BILINEAR, CUBIC, and ...
22
votes
3answers
5k views

What is Lanczos resampling useful for in a spatial context?

GDAL includes a resampling method beyond the normal mix of nearest neighbor, bilinear, cubic and splines: "Lanczos windowed sinc resampling". I understand that its a convolution filter, but unlike ...
3
votes
1answer
367 views

Converting dataset between coordinate systems

I'm working with NOAA's PRECipitation REConstruction over Land dataset, and am looking for an efficient way to sample the data by pixels on NASA's MODIS grid, using open source tools. The PRECL data ...
14
votes
4answers
17k views

How do you decide what interpolation method to use for resampling raster data?

The question pretty much says it all; are there hard and fast rules about which interpolation methods are suited to each kind of raster data? Any Golden rules, rules of thumb? Good books or articles ...