Questions tagged [raster]
Raster is a data format consisting of regular grids of values, usually stored in an image-like format.
6,532
questions
0
votes
0answers
10 views
Preventing Base Map is getting converted after loading the chart as a layer in MapInfo?
Whenever I am loading the chart into mapinfo using MapXtreme the basemap is getting converted. Because of which the chart is not coming in the right place. Can you please check my code what I am doing ...
1
vote
0answers
8 views
Leaflet - scale tiles for missing zoom levels
I have two sets of tiles. One for zoom level 10 and one for zoom level 14. However, I want to be able to see tiles on my map at zoom levels 9 through 15. For the nonexistent sets of tiles I want to ...
0
votes
0answers
8 views
GDAL Rasterize (Vector to Raster) not working with any extent
I am attempting to rasterize a road layer and neither the GRASS nor GDAL routines for this are working in QGIS 3.8.2.
All of my data is in UTM.
Here is my input (GDAL):
{ 'BURN' : 0, 'DATA_TYPE' : ...
0
votes
0answers
4 views
Raster to polygons in Google Earth Engine with connectivity restriction [on hold]
I am working with data from the USGS National Land Cover Database (https://developers.google.com/earth-engine/datasets/catalog/USGS_NLCD).
I would like to extract the data representing urban surfaces ...
0
votes
0answers
4 views
Invalid pointer returned from “GDALOpen”
I've create a model for upload a raster into my GeoDjango project.
models.py
from django.contrib.gis.db import models as geomodels
from django.db import models
class RasterMap(models.Model):
...
1
vote
1answer
28 views
Interpolating raster data with PostGIS
I'm currently using CDO to extract data from netCDF files containing satellite meteorological data. In the netCDF file points have a resolution of 0.5 degrees, so when data for a specific coordinate x,...
1
vote
0answers
21 views
Strange output while calculating raster in QGIS
I've encountered the following problem frequently when I am using the raster calculator, even though sometimes the calculator works. However, I cannot figure out the difference between the times it ...
-1
votes
0answers
13 views
Clip polygon vector on Master map [on hold]
I am using ArcGIS and would like to clip the polygon on the basemap layer. Does anyone know how to do it?
1
vote
1answer
6 views
Mapserver - dynamic contrast stretching for custom COLORRANGE's
In MapServer, is there a way to use the PROCESSING "SCALE=AUTO" directive to get dynamic (current extent) contrast stretching with custom colorranges? When I test my mapfile (relevant layer part below)...
2
votes
0answers
18 views
Querying / seting up PostGIS (raster) table to efficiently get all bands at once?
I have created a PostGIS raster table from raster2psql. I have use cases where I might have bands sizes of 114 to 670 bands inside a raster (The number is consistent across a given dataset.)
My ...
-1
votes
1answer
27 views
Using R to extract data from Global Aridity Index and Potential Evapotranspiration (ET0) Climate Database v2?
I have a latitude/longitude dataset; I wish to extract the aridity index for each of location in R.
I am new to R, so I seek basic code along with the required libraries.
0
votes
0answers
14 views
Selection by Location on Raster, Using a Vector Layer
I'm trying to identify raster cells by location to eventually convert them to vector polygons, and then add them to an existing vector layer. Below is a picture to illustrate the problem.
The green ...
1
vote
1answer
28 views
R raster to shapefile
I created a raster with the function rasterFromXYZ() in R using a dataframe with coordinates and the value of a variable, the result was this:
plot(raster1)
which is exactly what I need. Now I just ...
2
votes
0answers
23 views
Multiple conditional statements for raster calculation in R
In the context of a RUSLE erosion modelling I would like to calculate the sum of precipitation at the entry date of phenological phases.
Suppose I have 13 grids, one of which is the phenophase entry ...
1
vote
1answer
18 views
(QGIS) Shapefile with attribute table: Convert it to raster burning values of each polygon to the raster. “Heatmap”
I am working on QGis with a shapefile with an attribute table, I have created this shapefile through "Vector->Analysis tools->Count Points in Polygon", so this new shapefile got the count in the ...
2
votes
0answers
22 views
Batch process aligning multiple rasters in QGIS
I would like to know if there´s a way to run a batch process that consists in aligning (changing cell size from 10 to 20 in Sentinel 2 imagery) in QGIS 3.4?
I need to resample band #8 (resolution 10m)...
3
votes
1answer
33 views
Problems with analyzing MODIS Aerosol Optical Depth
I want to extract AOD from the following hd5 file.Would be grateful for any help. Objective is to have a tif file projected in EPSG:4326 with values of all 3 bands.
https://e4ftl01.cr.usgs.gov/MOTA/...
0
votes
0answers
27 views
Merging different resolution DEMs in ArcMap? [duplicate]
I have 4 DEMs I would like to merge/mosaic together into 1 - each have a different cell size. I am using ArcMap 10.6.1
Things to note:
- All have 1 band
- There is 1m, 2m, 5m & 10m DEMs
- ...
0
votes
0answers
29 views
What is the most powerful software for visualizing very big PostGIS raster coverages? [on hold]
I have some very large raster coverages in PostGIS. I tried to visualize them in QGIS but it crashes. I think the raster is too big because when I clip it QGIS can visualize it easily.
The raster ...
1
vote
2answers
24 views
Visualizing raster coverage of PostGIS in OpenJUMP?
I am new to OpenJUMP and I am trying to use this software for visualizing PostGIS rasters.
I was able to display vector layers of PostGIS in OpenJUMP but I cannot display raster tables. Do you know ...
1
vote
0answers
21 views
How to create a raster map in QGIS that includes the distance to the nearest road multiplied by another variable included in a vector file?
I am using QGIS (v. 3.4). I have a vector file (.shp) with the main roads of my city including the average traffic load of each segment. I would like to create a map with the inverse distance to the ...
0
votes
0answers
15 views
ArcMap displays 0 0 Decimal Degrees for rasters with correct information
I have multiple rasters when opened in arcmap they show 0 0 Deciaml degrees at the right bottom of arcmap
the information
this is the same raster.
what is problem?
1
vote
2answers
96 views
Reading big raster getting warnings using GDAL Python
I am trying to use GDAL Python API to deal with some big raster, and when I read these rasters into Python, I get warnings like that:
Warning 1: TIFFFetchNormalTag:ASCII value for tag "GeoASCIIParams"...
3
votes
2answers
50 views
Upscaling Raster Data in Python
Solved
@user2856 helped me crack this.
import geopandas as gpd
import rasterio as rio
from rasterio import features
from rasterio import Affine
from rasterio.enums import Resampling
results = []
...
1
vote
1answer
19 views
Setting correct start and end time series for Savitzky-Golay in R
I am trying to smoothen my raster stack using Savitzky-Golay method. I am following the workaround from HERE but my problem is setting start and end of my time-series raster. My series of images were ...
2
votes
1answer
35 views
Shapefile to polygon, then edit the polygon in order to use it as a mold
I am working on QGIS with a shapefile:
I transform it through Raster-> Conversion-> Polygonize
Then I eliminate some parts (Sea), and those that are bigger than one single square of grid but are ...
1
vote
1answer
28 views
QGIS: Clip Raster by Mask Layer-permanently remove black edges
I want to introduce geotiff images generated in QGIS by clipping ortho imagery to a shapefile into matlab. However, the clipped raster images come with black borders. I managed to remove them in QGIS (...
0
votes
1answer
35 views
Raster smoothing - assigning each raster the average value of its neighbors
I have a raster world map of population densities at a resolution of 30 arc seconds. For each raster, I want to find out the average density of neighbors within a certain distance (e.g. 0.1 degrees). ...
2
votes
0answers
40 views
Extract population density data from a raster by shapefile
I'm trying to extract population density data from a raster by shapefile. I get NaN values, but I think my problem is further upstream at the raster level. I don't do much GIS work, so I'm likely ...
2
votes
1answer
44 views
How to set CRS of many rasters in R
I have a set of rasters that I've had trouble reprojecting to Robinson. It fails without errors, the crs changes but the extent doesn't convert to metres and it doesn't plot properly. Sources say EPSG:...
1
vote
1answer
19 views
Getting lat/lon of maximum value in raster using PostGIS?
I can get the max value from a raster column using PostGIS and
SELECT max(ST_SummaryStats(rast, TRUE))."max") FROM schema.table;
How do I take that value and get its coordinate(s)?
2
votes
0answers
30 views
MapServer Query Raster for Pixel Value at Point
I am working with a MapServer and a map file that is displaying a color-relief image.
LAYER
NAME "sum"
DATA "sum.vrt"
TYPE RASTER
STATUS ...
-1
votes
0answers
29 views
ESRI-GRID data or ASCII GRID data [closed]
I'm trying to make a poster with different climate projections for a river basin in Thailand. I would like to make a box & whisker plot for each month in 2030 (will repeat this for other years).
...
1
vote
0answers
35 views
Using Raster Dataset in QGIS?
I've been trying to convert all my ArcGis projects into QGIS 3.4.10.
I have a problem with my raster data sets. They're all .tiff data and have the right projection but they still won't fit to my ...
0
votes
2answers
67 views
Shift in raster in python 3.6
I have a python script for a color anomaly detection study. I am attempting to create two rasters each with three classes: one raster representing a "target" and the other representing "background", ...
0
votes
1answer
29 views
Generating random raster using weights with negative binomial distribution using R?
I'm trying to generate "species counts" in raster form -- essentially, the number of individuals in a species in a raster cell. I'd like to use the negative binomial distribution to do so. Normally I ...
0
votes
1answer
23 views
Creating pre-determined size polygon with average raster value using ArcGIS Desktop?
I have a simple raster with multiple pixels (5 million+), and each pixel has a value from 0-1 representing % values. So one pixel might be 0.361 (36%) and another might be 0.053 (5%).
Is it possible ...
2
votes
2answers
33 views
Create cumulative raster layer in QGIS
I need to create a new raster layer with cumulative values for 16 raster layers. For context, each raster layer represents an 'areas burnt' in a given year - essentially, I want a new layer that ...
0
votes
1answer
23 views
GRASS GIS: creating raster with a certain gradient and extent
Constraints
- Use only GRASS GIS
- Automated using pyGRASS
Input
DEM
River raster OR river as vector (both are computed)
gradient of the valley (as a float)
vector line with direction and magnitude ...
1
vote
1answer
35 views
Create multiband raster from a single band raster with fields
I have a raster which has a single band containing what is effectively a lookup code. When I open the raster in ArcMap and open the attribute table I can see several fields which I guess come from the ...
2
votes
1answer
14 views
R scripting for hillShade
I'm trying to use a csv table with angle and azimuth values to compute a hillshade on the same area at different dates.
I'm using for and each date to extract the correct values, but it doesn't seem ...
1
vote
2answers
40 views
Selecting all the pixels in a raster coverage that have a specific pixel value? (in PostGIS raster)
I have a land use map in the format of TIFF. I imported this file as a table in PostGIS using raster2pgsql. The land use file has 7 different classes.
How can I select all those pixels that have the ...
0
votes
0answers
15 views
Grid specification with multiple z fields/attributes in VRT-file in GDAL
I am trying to transform a csv file into a tiff-file (raster). As a first step I am creating a VRT-file. My csv has the following row structure:
E_KOORD,N_KOORD,Z1,Z2,Z3
How do I correctly specify ...
-1
votes
0answers
16 views
Correlation between multiple raster layers in r
I have five different raster layers, each one of which represents a species distribution model for a given species. The cells within a raster layer give a probability between 0 and 1 of that species ...
1
vote
0answers
25 views
Calculating percentage/fraction of thematic pixels with coarser resampled pixels in QGIS/GRASS
I am using QGIS 3.4.9 on Mac OS10.13.6.
How can I edit raster data type to change it from thematic to continuous/quantitative?
details:
I am trying to calculate the fractional (percentage) ...
-1
votes
1answer
33 views
Extracting data from ASCII file? [closed]
I have ASCII files for a country that map altitude. I'd like to extract information on slopes for specific cities in my country. My goal is to have at least a rough idea of physical constraints in ...
1
vote
0answers
28 views
Converting non projected x,y coordinate into a specific projection in a 2D array
I created a 2D array and after applying Gaussian filter I find centroid of all the connected pixels with values equal to 1 and then
save it with the projection EPSG:3413.
Using skimage.measure.label, ...
0
votes
1answer
29 views
Using QGIS to create a GeoTIFF raster of Google Earth import
I've managed to link QGIS3 to Google Earth via XYZ tiles. I would like to convert the Google Earth map shown to a GeoTIFF raster (to save on memory?). I try and export the Google Earth layer to a ...
1
vote
0answers
28 views
Analysing local features on rasters using ArcGIS Pro?
I have several raster datasets representing the elevation on a beach (See Picture).
The beach topography include beach cusps (which represent local max on the beach).
I want to extract some ...
1
vote
1answer
22 views
Selecting a polygon area in a raster image - rasterio.mask vs roipoly
How should I select a polygon area in a raster image?
So far, I have seen two methods:
use a vector mask or a shapefile (some examples here: http://www2.geog.ucl.ac.uk/~plewis/geogg122-2011-12/...
