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

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223 views

Displaying numbers of single band raster layer in QGIS without additional vector layer?

I wonder if there is a raster symbolizer in QGIS with a label option, that renders the cell values as labels of single band raster layer, a scalar field. The standard raster symbolizer dialog in ...
8
votes
1answer
435 views

How to fix “Raster layer: Provider is not valid” error when loading PostGIS rasters?

I compiled and installed the current QGIS master as usual and I imported some raster data into my postgres 9.3 database with postgis 2.0.2 extension. Whenever I try to import the raster data into qgis ...
7
votes
1answer
378 views

How to store Large Raster Images of Equipotential Surface Generation Using Monte Carlo Simulation?

I have a large (1GB+) raster that I am using as the base for the generation of an equipotential surface. This is to assess the accuracy of DEMs derived from another source. In situ observation is ...
6
votes
1answer
143 views

Automate Exporting of Rasters Using Renderer in ArcGIS

It is possible to export rasters in ArcMap by right clicking the layer-> Data-> Export: You can then click 'Use Renderer' check box to ensure the image you export uses the current ...
5
votes
1answer
117 views

Optimizing Python GDAL ReadAsArray

I am using the GDAL ReadAsArray method to work with raster data using numpy (specifically reclassification). As my rasters are large, I process the arrays in blocks, iterating though each block and ...
5
votes
1answer
961 views

How to force RGB in a raster in QGIS?

I have rasters in 1 band 64bits float that represent real data values and for which I can set min and max using the stretch to min and max option in QGIS. I would like to convert these rasters to RGB ...
4
votes
1answer
32 views

Grid size of a Digital Elevation Model developed from topographic surveyed elevation contour line?

I have generated a Digital Elevation Model from elevation contour line. I got these elevation contour line at 20 cm interval from DGPS survey. What would be the grid size of generated DEM in "m". ...
4
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20 views

Conditional Combine Rasters and Track which Raster pixel used

I have 6 rasters with pixel values ranging from 0 to 1. I want to extract the highest pixel values from each raster to create a new raster, but also have a way to show which raster the highest value ...
4
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45 views

Is it possible to locate a specific marker point on a raster using python and use that location for georeferencing

I have several scans of the same map, which I would like to georeference. I can not use arcpy.WarpFromFile_management(...) as the rasters are slightly different due to scanning. Is there a ...
4
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1answer
110 views

Does gdal_calc only support 26 input raster files at a time?

In gdal_calc.py, input files are specified with letters A-Z. Here are two files, input.tif and input2.tif, being averaged into result.tif: gdal_calc.py -A input.tif -B input2.tif ...
4
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1answer
152 views

Iterate through rasters in subfolders using Model Builder

I have a directory folder of precipitation data; within this folder are subfolders for years 1901-2014. In each of these subfolders are 12 .asc grid files; each file represents a month of the year ...
4
votes
1answer
499 views

ArcGIS model builder: How to reclassify 16,000+ rasters and do weighted sums on these rasters per year?

I've been trying to build a model in model builder (ArcGIS 10.1) which can do the following task: I have a folder full of ca. 16,000 raster files (.asc) representing mean temperatures for each day ...
3
votes
1answer
42 views

QGIS Has Rendering Error on JP2000 Raster. Works in ArcGIS

I've got a large .jp2 raster file that was created using 'Mosaic to New Raster' in ArcGIS. I'm trying to open it in QGIS 2.8.6 (I've tried 2.8.14 as well) and am getting a vertical line that won't ...
3
votes
1answer
59 views

Build a table with columns of raster values from multiple raster datasets, using Python, GDAL, or PyQGIS?

I have a series of raster datasets, clipped to the same extent, with matching cell resolutions, each of which represent land surface temperatures (LST) captured by the MODIS sensor. Each raster ...
3
votes
1answer
36 views

Displaying Raster Source Information

I have a large number of raster files I'm working on. I need to figure out how each of the files was processed from. I have a composite land cover map and would like to view the file names and ...
3
votes
1answer
75 views

What is faster - a matrix, raster or a dataframe?

I have rasters over which I am performing mathematical operations. For example, where I need to calculate flow distance or distance between two grid points. What format is generally considered faster ...
3
votes
1answer
38 views

Help with Rastercalculator - Filter areas with a certain height difference

I'm struggeling a little bit with the rastercalculator tool of QGIS. At the moment I am working with a DSM and a DTM. My aim is to filter all wind turbines out of the DSM and replace it with the ...
3
votes
1answer
272 views

Split raster into tiles

I have a raster that needs to be split into tiles (each tile a new raster). I have a Shape file with multiple polygons (these polygons are how I want the raster split). I have Gdal and QGIS. Any ...
3
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1answer
91 views

Storing a coverage in a JDBC database

There is another question about raster data for GeoServer. Conditions: - PostGIS 2.0.3 and PostgreSQl 9.2. - I followed: ...
3
votes
1answer
103 views

Least cost path with one-off cost for highest elevation

I'm trying to write a script to calculate the least cost path between two cells on a raster. I'm reasonably familiar with the approaches used by tools such as GRASS GIS's r.cost and ArcGIS's ...
3
votes
1answer
170 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 ...
3
votes
1answer
454 views

How to count and rasterize polygon overlaps in QGIS?

I have a large number of polygons that are overlapping. I'd like to create a heat map and plan on using raster calculation to do this. My plan: to give each polygon a raster value of 1, and adding ...
3
votes
1answer
81 views

How to always see all band values with Identify Features of QGIS?

Does anyone know if it is possible to get the Identify Features tool in QGIS to show the band values for all the layers shown in the results window? To clarify, whilst I have several bands "showing" ...
3
votes
1answer
381 views

An error in raster calculator in Arcgis

I wrote and ran this formula in raster calculator in ARCGIS. But the following error gets me into trouble. Does anyone have a suggestion to overcome this? Here is the formula I wrote and the error ...
2
votes
1answer
34 views

Importing large .asc files into QGIS

I've been given two .asc files containing a 1m raster data from a LiDAR survey. I only have access to QGIS.2.14.1 (which I'am using for the 1st time only having previous experience with ArcGIS) and ...
2
votes
1answer
25 views

How can I calculate the percent of a raster cell covered by a polygon?

First, I am going to try and intersect a raster and a polygon shapefile. I'm not 100% sure how to do this (or if I need to do this for the next step), so if you have any suggestions please let me ...
2
votes
1answer
25 views

Raster rotation on QGIS

How can I rotate a raster layer (global land-mass) to make the 180 deg longitude the center of the map (using QGIS)? 'rotate' function in R is simple but not accurate. Raster has 'longlat' projection ...
2
votes
1answer
31 views

Determining hardware requirements for mosaic dataset operation to work properly?

I've been building mosaic datasets in ArcGIS, but have been having mixed results depending largely on the number of cores on the computer being used to build the mosaic dataset. For example, on a ...
2
votes
1answer
25 views

Mouse-over raster surface to stream values to text file ArcGIS

This is a weird one. I have a user who wants to add a statistical surface to ArcMap and then mouse-over the raster surface and stream those values (z) to a text file. MouseTips can show underlying ...
2
votes
1answer
35 views

ArcMAP / R: Convert raster pixels to Long and Lat

I have downloaded a raster, which has the following information. Item Data Date 2015-01-03 00:00:00 Product cold partial sst Satellite NOAA-18 Direction Unknown Dimension 1596 x 1617 BPP ...
2
votes
1answer
39 views

How do you extract the mean fire frequency (raster) for each point within a given buffer size using R?

I am trying to extract fire data (mean and max fire frequency) for each point within a given buffer size (250m) around multiple points. Currently, my point data is in Lat and Long. For the raster ...
2
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1answer
11 views

How to extract values from multiple raster dataset from a location point in one single dbf?

Suppose I have 250 raster and my only concern is just a single point. The raster is arranged by ascending date. So if I extract a point value based on the order into one single file then I can graph ...
2
votes
1answer
26 views

Create MosaicDataset with 12 Bits

I'm using ArcGIS 10.3.1, and I want to create a mosaic dataset, but my rasters are in 12 bits, and a mosaic doesn't have this option. What can I do?
2
votes
1answer
35 views

Why is ArcMap reverting 4-band raster settings?

ArcMap keeps redrawing my 4 band false colour image in standard 3 colour bands. As you can see below I have my 4 band data set to auto display as (4,1,2 - infrared, red, green). When I bring in an ...
2
votes
1answer
79 views

Raster statistics for polygon areas PostGIS

I'm trying to get zonal raster statistics for each polygon area. I have used the following method from this site: SELECT bufid, (ST_SummaryStatsAgg(ST_Clip(rast, geom, true))).* FROM rasttable, ...
2
votes
1answer
42 views

Combining two euclidean distance rasters in Raster Calculator

I have two euclidean disance rasters and would like to combine them for use in a multi criteria evaluation. Could anyone advise me on the syntax to use within Raster Calculator (ArcGIS 10.3.1)? There ...
2
votes
1answer
72 views

What is limit to physical number of raster TIFFS that can be placed in QGIS?

Can anyone please let me know if there is a limit to the physical number of raster TIFFS that can be placed in QGIS? I am trying to bring in a large number of StreetView tiffs from the Ordnance ...
2
votes
1answer
53 views

replace raster cell values with values in a .csv

I'm looking for a simple way to replace the value field in GRID format with values that I have in a csv. It would be much like doing a join, where the GRID and the csv have a FEATUREID and then ...
2
votes
1answer
30 views

Mosaic rasterstacks based on minimum of certain layer?

I am trying to mosaic 42 remote sensing rasterstacks (with 250 bands) based on the criterion that in overlapping areas, the pixel should be taken that has the most nadir viewing angle Beside my ...
2
votes
1answer
736 views

How to fill holes/missing values in XYZ data / a DEM with QGIS?

I have equidistant XYZ point (text) data that I used to create a point grid. However, it's not perfect - there are some holes. I then created a DSM raster from it, which obviously has the holes too. ...
2
votes
1answer
121 views

Is there a better way to convert Raster to Point data? Don't need one point for every cell

I need to convert raster data to point data so I can use the points for interpolation via kriging. My problem is that my resolution is 5 ft and I'm working on a whole city. The data I am converting ...
2
votes
1answer
406 views

How to extract percentage of land cover from a raster according to multiple shapefiles?

I have a raster map that represents land cover of a region, and different shapefiles (total 120) in the same region. I want to know the percentage of every land cover for each shapefile. For example, ...
2
votes
1answer
157 views

Defining the output raster resolution when rasterizing a vector?

I have a vector file which I want to rasterize and adjust its resolution to the reference map, in QGIS. I tried spatial_sync_raster function in R to set all the rasters into the same resolution as ...
2
votes
1answer
277 views

Unsupervised raster classification using GDAL

Is there an equivalent in GDAL to the Arcpy ISO data unsupervised classification tool, or a series of methods using GDAL/python that can accomplish this?
2
votes
1answer
120 views

Getting Uncompressed Size of Raster using ArcObjects?

How can we get the Uncompressed Size of a raster as shown in the layer properties below using ArcObjects?
2
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1answer
56 views

Polyline frequency to raster

I have some animal tracking data in the form of a polyline shapefile and want to convert this to a raster so that each pixel is given a value of 1 for every instance in which a line crosses it. I've ...
2
votes
1answer
157 views

Smooth out lines in QGIS

I have taken a raster image and coverted it to a vector file. It is an OS map which shows field boundaries etc. As the vector file has been created from the pixelated raster file the lines are ...
2
votes
1answer
186 views

Why am I losing part of my raster when I reproject?

QGIS 2.0 Working with tiff raster file. Reprojections are in WGS84 Mercator. Here is my problem: I am trying to use buffers or urban areas to analyze light intensity on a raster layer. I want 30 ...
2
votes
1answer
414 views

Can I update the service on ArcGIS for Server programmatically?

There is Windows Service. This service adds user raster data to the Raster Dataset in sde database. The Raster Dataset registred on the ArcGis Server. This Raster Dataset also was publishing on ...
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207 views

SAGA grid VRT, file how to apply a LUT?

I've created a heap of saga grid files for some hydro survey work. I'm looking at a way to read these into a mapguide raster/grid layer, I'm able to load up the grids using a vrt file, I can't figure ...