GDAL Virtual Dataset (XML based)

learn more… | top users | synonyms

4
votes
0answers
43 views

OS terrain 50: .vrt from zip files

I tried to follow what was suggested in How to use OS Terrain 50 in QGIS, but I got the following problem: in spite of being generally able to generate .vrt files using gdalbuildvrt from unzipped ...
13
votes
1answer
1k views

Connecting ArcSDE to Quantum GIS for dummies?

I really have a need to be able to connect to and edit ArcSDE data in Quantum GIS. This question has been asked before and apparently is possible, but the instructions are just not specific enough ...
2
votes
1answer
18 views

How to create multiple external overviews for a geotiff with gdal?

I want to have mutiple overview files (one for each overview level) for a GeoTiff, so I'm able to edit this files in a raster editor. How can this be done? Unfortunately, gdaladdo -ro creates only ...
0
votes
0answers
36 views

GDAL error in QGIS application displaying VRT files

I am working with a standalone app build with QGIS 2.8.1 on a CentOs7 machine. I got a new DTED data set which raises errors "somewhere" in the app. The app doesn't read the .dt? files directly, but ...
6
votes
0answers
58 views

QGIS: large .vrt indexing

I have a large number of small tiles merged into a single VRT. The rasters are only viewed at large scale, so only a few of them are visible at the same time. The map refresh in qgis is slowing down ...
3
votes
1answer
44 views

GDAL VRT files get corrupted by reading

In my stand-alone QGIS app I am using vrt files of DTED rasters. All vrt files are build with the same Python code and have the same structure, codepage etc. I use them for display only. ...
5
votes
2answers
289 views

GDAL (or other open-source) equivalent of Arc's Point To Raster Tool

I'm trying to convert a python script that relies on arcpy into one that only relies on open source modules, but I'm having some trouble. The bulk of my processing lies in one Arc tool "Point to ...
1
vote
0answers
25 views

How to dynamically change the draw-order of geotiff rasters in QGIS?

In ArcGIS it is possible, via raster mosaics, to choose the raster order depending on various methods. One such method is the center method. The raster that is closest to the coordinate of the center ...
1
vote
1answer
108 views

Where vrt files store the location of the tiles

I have thousand of tif tiles and a vrt file, generated by using gdalbuildvrt. At the moment they are at the same folder level in the system, but if I open the vrt file with Notepad I cannot find any ...
2
votes
2answers
184 views

How to convert CSV file in VRT

Im a geomatics student. For the treatment I would like to make, I use the gdal executable in QGIS file, with a DOS command. I have a csv file like this (test.csv) : X Y -5.48 42.81 -4.78 ...
0
votes
0answers
98 views

How to build .vrt of shapefiles?

I've a huge number of shapefiles and I would like to create a VRT as I do with gdalbuilvrt for raster. I find here https://github.com/dwtkns/gdal-cheat-sheet that it should be possible and the format ...
1
vote
1answer
46 views

Pulling a cvs file from a website into QGIS with the ability to automatically refresh.

I am attempting to pull a cvs file from a website that is updated daily. I would like to have a process that can automatically perform the process and save daily as a new layer. The cvs file is ...
2
votes
1answer
83 views

Overviews: to tiles or .vrt, or both?

When using vrt to mosaic on the fly large collections of images, is it better to add overviews (pyramids) to the individual rasters or to the final .vrt, or both? (Where "better" means finding the ...
5
votes
1answer
1k views

ArcGIS Raster Mosaic Dataset and GDAL VRT, when to use?

ArcGIS Desktop has a the Raster Mosaic Dataset, QGIS and friends have Virtual Raster Tables. A skim of the documentation reveals much similarity. They both create or enable an alternate ...
0
votes
0answers
75 views

Cutting a shape from a VRT file with gdal warp

I have a couple of overlapping tif files which I want first to merge and then to clip a shape file from the result tif. The problem is that the tifs are pretty big and when the tiffs are overlapping ...
6
votes
1answer
1k views

Python equivalent of gdalbuildvrt

Is there a way to perform the same task as the gdalbuildvrt utility using GDAL Python bindings? So far I have not found any way to do this other than creating a vrt of a single dataset and manually ...
0
votes
0answers
189 views

gdal ReadAsArray returning NoneType

I'm trying to read in several rasters as array using gdal in a python script, but I keep getting NoneType returned and can't figure out why. The process is this: 1. Use gdalbuildvrt ...
2
votes
0answers
109 views

QGIS extremely slow to clip vrt on Mac

I've been using QGIS 2.6 (Brighton) happily for awhile but suddenly it became extremely slow during certain operations, after being reasonably fast in past use. I'm merging NAIP JP2 files to virtual ...
0
votes
1answer
166 views

How to use gdal_grid with VRT?

Hi folk's it seems to be that I'm to stupid to use gdal_grid. I' have file called dgm-10-epsg-32633.csv with equidistant samples 10x10m in this form. X,Y,Z 386700,6068670.000,.000 ...
0
votes
0answers
204 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 ...
5
votes
1answer
106 views

Reprojecting a CSV file using ogr2ogr?

I am trying to convert a CSV with fields in one projection system (EPSG:27700) to fields in another (EPSG:4326). I have made a VRT file called landfill.vrt, in the same directory as my CSV file, ...
1
vote
2answers
251 views

gdal_grid has some problem with reading vrt file

I am using gdal_grid module(from gdal 1.10) and it has some problem with reading the vrt file. I checked this link but it does not work. gdal_grid problem reading vrt file The command is ...
1
vote
1answer
55 views

Efficiently working with converting vrt rasters to greyscale in QGIS?

I have large raster tile sets working well in QGIS (Ordnance Survey UK data). Sometimes I want to grey/fade these to make my data clearer to see. Attempting to access properties on QGIS for the VRT ...
1
vote
1answer
215 views

How to define layer style for KML layer within OGR Virtual Format?

I have the following OGR virtual format data source, which includes a few GeoJSON files and one KML file: <OGRVRTDataSource> <OGRVRTUnionLayer name="union"> ...
1
vote
1answer
250 views

How to Set the Vertical Coordinate system when creating 3D Shapefile?

I have data of wells in CSV format, which I'm converting to a 3D shapefile, using ogr2ogr. The latitude and longitude are in WGS84, while the depth is from the WGS84 geoid. I have the OSGeo4W ...
2
votes
1answer
400 views

Add band to GDAL VRT dataset and convert to TIFF

I'm trying to add a band to a TIFF dataset by converting it to a VRT format and using the AddBand() function, then convert it back to a TIFF to access the band and write the data. Here is an example ...
0
votes
1answer
125 views

Gdal_grid gives blank .tiff file after conversion

After using gdal_grid I get blank .tiff file. I use the following .vrt file : <OGRVRTDataSource> <OGRVRTLayer name="p"> <SrcDataSource>p.csv</SrcDataSource> ...
2
votes
1answer
336 views

gdal_grid with CSV file and VRT “No point geometry found on layer”

Given the following .vrt file which I manually created: <OGRVRTDataSource> <OGRVRTLayer name="DGM5_BE"> <SrcDataSource>DGM5_BE.txt</SrcDataSource> ...
0
votes
1answer
154 views

Creating an OVF file for connecting Oracle and QGIS

I'm trying to create an OGR file that can be opened in QGIS that pulls in vector data from an Oracle Database. I've tried a few combinations of things but can't seem to get anything to work. I've few ...
3
votes
2answers
517 views

How practical is this workflow, tiling from a complex, multi-step GDAL VRT?

This is probably a cw-candidate, but here goes.. I've got 1002 ~100 MB (5000'x5000') .tif files in a state plane (transverse merc) projection comprising a county-wide, 1-ft aerial dataset. After two ...
0
votes
0answers
185 views

VRT vs KML superoverlay

We've got GB's of raster data that I want to make available as mosaics with overviews internally within my office. We have people using ArcGIS (although we are never all at the same version) and we ...
1
vote
0answers
119 views

How to prevent transparent borders (collars) of a tif wipe out overlapping regions of adjecent tif while using gdalbuildvrt

I have a set of Geotifs that have got transparent borders (collars) of irregular shapes & dimensions around them. First I created a VRT over this set of Geotifs through gdalbuildvrt. Then I ...
1
vote
2answers
341 views

Some tiff not included on a vrt index

I have some tiff files and I'm trying to generate a vrt index with gdal tool, gdalbuildvrt. I run this command: gdalbuildvrt orto_index.vrt -srcnodata "0 0 0" -vrtnodata "0 0 0" *.tif and throws ...
1
vote
1answer
260 views

Set a RANGE of values as nodata in a .vrt?

Is it possible to set a range of values to nodata in a vrt file? How? I have some elevation models with incorrect values, down in the -15,000s. I could just clip the rasters along that edge, or apply ...
3
votes
2answers
489 views

Python, GDAL, VRT: help wth code efficiency and processing time

I'm going to attempt to make this question as succinct as possible while still including relevant information, as I have trouble with being concise and am trying to avoid writing unnecessary stuff. ...
1
vote
1answer
376 views

gdalbuildvrt error, when using in Python

I am new to python/GDAL and am running into perhaps a trivial issue. This may stem from the fact that I don't really understand how to use GDAL properly in python, or something careless, but even ...
6
votes
1answer
314 views

ogr2ogr csv conversion with latlon in one column

I have a csv with "lat\,lon" in a single column. I am trying to convert it with ogr2ogr to another format, and cannot figure out how to format the VRT file to accept this format. I cannot do ...
3
votes
1answer
279 views

How I can incorporate results of histogram stretching into georeferenced image?

I have one channel 8 bit raster and when I open it in QGIS with histogram stretching "on the fly" it looks fine. How I can recalculate original raster accordingly changed histogram?
1
vote
1answer
288 views

How to get WGS84 lat lon bounds from a VRT file

I have vrt files generated using gdalbuildvrt that reference GeoTiffs referenced using the NZTM coordinate system. Is there an easy way to determine the bounds as WGS84 latitude longitude ...
1
vote
1answer
312 views

Writing array to vrt

I would like to write an array from a single band image to a 3 band vrt where each band has the ColorInterpretation() tag of red, green, blue respectively. My code below; from osgeo import gdal ...
1
vote
2answers
783 views

Having problems creating VRT in QGIS from png files

This is similar to a question asked by someone else, re OS tiles, however, there is a difference! I am a bit of a amateur in GIS and python, but if I take it slow I can usually just about work it out! ...
1
vote
0answers
107 views

Size of output geotiff file not as in the .vrt file

I have the following vrt file (input.vrt) with GCPs in EPSG:3857 <VRTDataset rasterXSize="5409" rasterYSize="5408"> <Metadata /> <Metadata domain="IMAGE_STRUCTURE"> <MDI ...
1
vote
0answers
281 views

Issues with building a VRT. from OS map tiles in QGIS

I am trying to speed up rendering of OS raster map tiles in QGIS. The tiles are 1:10k Tiffs - about 130 of them. When I attempt to build the VRT it says complete, then it shows up an error ...
6
votes
1answer
4k views

GDAL VRT Format - do i understand the concept?

Okay, so im a little fed up with different raster-in-database solutions that I tried over the last 2 weeks which don't work currently (Postgis raster) or cant handle my volume of data (Rasterlite), so ...