GDAL (Geospatial Data Abstraction Library) is an open source translator library & set of command-line utilities for processing raster spatial data formats. As a library, it presents a single abstract data model to the calling application for all supported formats. It also comes with a variety of ...

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2
votes
1answer
160 views

Why does ogr's CreateLayer() return None?

Why does ogr's driver method CreateLayer return None? I'm using python 2.7 with gdal 1.9.1. path = r'D:\_tempAuto' out_shp = '%s\test_OGR.shp' % (path,) driver = ogr.GetDriverByName('ESRI ...
6
votes
2answers
322 views

How to use GDAL to convert Int16 data to Byte

I have some data with Int16 bands in HDF format. I want to convert this to Byte bands in GeoTIFF format. The data range for the Int16 is -2000 to 12000, so I want to map this to the Byte range 0 to ...
2
votes
1answer
639 views

merge raster images: error message procedure not found

I am using QGIS 1.8.0. Whenever I try to merge raster images I get the following error message: Traceback (most recent call last): File "C:\PROGRA~1\Quantum GIS Lisboa\bin\gdal_merge.py", line 36, ...
5
votes
1answer
278 views

Python/GDAL get unique values in discrete-valued raster

I would like to get some advice on the most efficient way to return a list of unique values of a discrete-valued raster using Python and GDAL. I had thought that the most obvious way would be to ...
6
votes
3answers
1k views

How do I extract a raster's extent in python?

I am looking for an easy way to extract a raster's extent in python. Currently, I am using gdalinfo and then parsing out the corner coordinates. The problem with this approach is that gdalinfo is ...
4
votes
1answer
1k views

Qgis - How to change GDAL version

im working on Ubuntu 12.04 server; i noticed this when i installed additional support for ECW format into the GDAL 1.9.1 which worked ok. Then i tried to add ECW files to Qgis but it said they still ...
1
vote
1answer
509 views

Why do I get different results with gdal_calc within the osgeo4w shell and QGIS' raster calculator?

I'm just wanting to make a simple map algebra operation in the osgeo4w shell using gdal_calc but I get wrong results when I divide one raster with the other. When I use the same rasters in QGIS and ...
4
votes
1answer
2k 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 ...
8
votes
2answers
4k views

How to fully load a raster into a numpy array?

I have been trying to check my filters on DEM raster for pattern recognition and it is always resulting in missing last rows and columns(like..20). I have tried with PIL library, image load. Then with ...
11
votes
1answer
2k views

How to access feature classes in file geodatabases with Python and GDAL?

I am trying to access a vector dataset in a ESRI File Geodatabase using Python + GDAL. I have successfully compiled GDAL with the file geodatabase API. The FileGDB driver is working correctly since ...
0
votes
1answer
678 views

gdalwarp results in incorrect extent

I have a GeoTIFF that's 172800x86400 on the MODIS "250 meter" Sinusoidal grid (more like 231.7, but who's counting?). (You can find its metadata at the bottom of this post.) This bounty of resolution ...
3
votes
2answers
330 views

Generate a pyramid of tiles by 1/2 scaling a higher zoom level

Given a set of tiles covering a large area at a particular zoom level (These are online on someone's tile server and will need scraping, but let's assume these are on disk if it's easier. With TMS ...
0
votes
2answers
676 views

How can I add a loop in gdal_translate? [duplicate]

Possible Duplicate: gdalwarp in a bash shell for loop I have several modis images (.hdf) from which I want to use only the one band (NDVI) and create a ".tif" image. I have already ...
2
votes
1answer
319 views

GDAL 1.9.1 ogr2ogr KML to PostGIS not incuding ExtendedData

I have a KML file utilizing a Schema in the document and ExtendedData in each placemark. The ExtendedData does not seem to pass in conversion to PostGIS or shapefile. Any assistance would be much ...
3
votes
0answers
363 views

How to compile GDAL with HDF4? (for dummies)

I need GDAL with both Shapefile and HDF4-Support, if possible in 64 bit. Since the normal GDAL-versions from http://www.gisinternals.com/sdk/ have Shapefile, but no HDF4 and the version from FWTools ...
2
votes
1answer
450 views

How to manage null values in QGIS

I made a merge of several AsterGdem blocks near Egypt and Israel. I have portions of the Dead and Mediterranean Seas. Since near Galilea elevations are below sea level this makes the following problem ...
0
votes
0answers
155 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 ...
1
vote
2answers
2k views

Clean way to install gdaltools plugin for QGIS on OSX

I have qgis 1.8.0 on osx mountain lion and am installing the gdaltools 1.2.29. I have run into a problem that a number of people are seeing. The plugin cannot find my gdal python (see below). ...
8
votes
1answer
2k views

GDAL RasterizeLayer Doesn't Burn All Polygons to Raster

I am trying to burn a shapefile to a raster using GDAL's RasterizeLayer. I pre-create an area of interest raster from a different shapefile, given a specific pixel size. This AOI then serves as a base ...
9
votes
1answer
1k views

Importing GDAL from Python window of ArcGIS for Desktop?

I am trying to run some Python code using the Python window in ArcGIS 10.1 that uses both the arcpy and gdal modules. However, when I try and import the gdal module I get an error: ImportError: No ...
0
votes
2answers
242 views

Why does gdalbuildvrt not allow these things?

I don't know why does gdalbuildvrt not allow: Unreferenced images Rotated images South up images Could someone throw some light? Many thanks in advance
2
votes
1answer
81 views

What should I expect in this case?

If while I'm executing gdalinfo against a raster layer I get a positive value for pixel size Y, what of these scenarios is possible? The raster's map coordinate system sets the origin of the data in ...
4
votes
1answer
461 views

raster algebra in python with rasters of different extents

I am trying to find out how to use GDAL & numpy modules to average a set of rasters....which are Sigma0 values from satellite passes at different times within a year. Each raster has been ...
3
votes
1answer
263 views

Projecting GCP points into translated file

I have file A.png and file B.png. I translate file A.png so i could translate it into B.png (creating multilayer file). Is there any easy way to get new GCP points coordinates so i could combine those ...
1
vote
0answers
236 views

Homebrew GDAL installation ECW or MrSID

I have experimented with installing gdal 1.9.1 via homebrew. It works wonderfully. Unfortunately, their is no real JP2000 support. I realize that JP2000 is supported by OpenJp2000, but that ...
3
votes
0answers
414 views

How to save table from PostgreSQL to MapInfo File?

I have two tables: 1 with geometry in WGS 2 with geometry in Local System I tried this: ogr2ogr -f "MapInfo File" output2.tab PG:"host=localhost user=postgres password=123456 dbname=postgis" -sql ...
2
votes
2answers
432 views

Using osgeo modules in ArcGIS10.1 and QGIS 1.8 python shells

This is related to an old question of mine - Issues with osgeo - qgis.core and arcpy modules Now in new versions of all the software QGIS Lisboa (1.8), ArcGIS 10.1 and pyScripter 2.5.3. They all use ...
0
votes
0answers
522 views

How to add ECW support to GDAL bundled with PostGIS Windows

I'm currently trying the new raster functionalities of PostGIS 2.0 and I successfully imported some GeoTIFF file into PostGIS (although it only find one band so it's all black and white for some ...
0
votes
1answer
419 views

Vector boundary generation -similar to Image Boundary

I want to automate the creation of boundary polygons from vector files. This is not footprint or extent creation (I already have scripts to do this). I want to create a tool similar to the QGIS, Image ...
1
vote
1answer
440 views

GDAL: C++ API to Convert Text file of Coordinate points to Raster Pixel line?

I am using GDAL to "Grow" areas form starting seed points. I have a text file listng the coordinates of my seed locations. The X,Y coordinates are in the coordinate system of a raster image. I want ...
1
vote
0answers
177 views

gdallocationinfo from C++?

I need a C++ API to convert x,y Image Coordinates in their native projection to output image pixel,line coordnates. I see the gdallocationinfo documentation, but no API for it. Where in online GDAL ...
3
votes
1answer
950 views

How do I split polygons that cross the dateline?

I have a dataset of country borders which I obtained from: http://thematicmapping.org/downloads/world_borders.php/ I have that dataset in both shp and SQL, but I'll put out there that I don't feel ...
1
vote
2answers
938 views

GDAL does ECW but QGIS (Linux !!) does not load ECW file

Followed instructions from various posts (each one with slight variations on the theme) and most of the time have no trouble getting the installed GDAL to accept ECW files. However, QGIS stubbornly ...
3
votes
1answer
405 views

How to stop writeOGR from abbreviating Field Names when using “ESRI Shapefile” driver

I'm currently using the following script to add some attribute data from a table to lots of individual shapefiles: library(rgdal) specieslist <- read.csv("SpeciesList1.txt", header=F) attdata ...
1
vote
3answers
566 views

Getting Field value for a given coordinate out of ESRI Shapefile using GDAL/OGR

I have a bunch of ESRI shapefiles that contain Land Cover data across Canada (provided by Geobase). I need to query the files and obtain the value of a certain field (called COVTYPE) in a given ...
6
votes
3answers
2k views

How to smooth / “reinterpolate” a raster with GDAL?

Short: I want to change the resolution of a raster and smooth the gray ramp like shown in the images bellow. The preference is to use GDAL, PIL or Numpy. Description: I'm kriging points into rasters ...
7
votes
2answers
507 views

How to catch PostgreSQL/PostGIS errors in GDAL/OGR Python bindings?

Is it possible to catch PostgreSQL output error messages in OGR after a query has failed? For example conn.ExecuteSQL('SELECT * FROM non_existing_table;') In Postgres this returns an error ...
9
votes
1answer
430 views

Is there a way to properly have GDAL raise exceptions in Python?

I am working with GDAL in Python and have wanted to get GDAL to raise exceptions so that I can do something useful with them. For instance if a file cannot be opened with gdal.Open() I would like to ...
0
votes
1answer
600 views

Qgis install can't find Gdal framework (Mac OS X 10.7)

After having installed Mac OS X 10.7 I can't install Quantum Gis as it maintains that I have not installe the GDAL Framework, which I have done (several times). Have anyone experienced the same ...
3
votes
1answer
646 views

Merging raster data with different resolutions

I need to merge different raster datasets which have one layer and contain discrete values to a layer stack. The resolutions of the data can have any value so not only multiples of the resolutions ...
2
votes
1answer
978 views

SID and/or ECW support on QGIS for Linux

Running QGIS on Ubuntu 11.04 and QGIS for Android on Galaxy Tab 10.1 (which is an awesome project by the way) NEED to figure out a way to get SID and/or ECW files loaded. Saw some posts about ...
1
vote
3answers
382 views

How can I translate a GML definition of SRS to a usual format (e.g. WKT or PROJ.4)?

From GDAL 1.9.0 a new utility is available: gdalsrsinfo. Although it can yield an XML (GML-based) definition from a source equivalent format or file, it seems that it can only read usual GDAL/OGR ...
2
votes
1answer
2k views

Converting Raster Data to Polygon data

I am trying to convert a raster data to polygon data. Previously I was using the shapefile.py to create point data on individual lat/lon on the raster. But that will create a Huge data and querying it ...
0
votes
2answers
150 views

gdal_translate made wrong tranforms

I have a geotiff file in UTM and units in meters. I used gdal_translate with this command : gdal_translate -of GTiff -a_nodata 0 -a_srs EPSG:4326 old.tif new.tif gdalinfo on new.tif shows that the ...
7
votes
2answers
736 views

What Open Source (command line/API) method is there to orthorectify and georeference an aerial image given telemetry data?

How can I take an image and orthorectify it automatically with open source software? The information associated with each image is: camera specs latitude, longitude, elevation of the camera ...
3
votes
3answers
1k views

Viewshed Analysis With GDAL

I am looking to perform a simple (one observer location) viewshed analysis on a standard DEM using GDAL (either python or .NET bindings). I have searched, but haven't found any readily available ...
2
votes
1answer
292 views

Crop collar from chart

I need advice on how to complete the following task: I have aeronautical charts covering parts of the US (example: http://aeronav.faa.gov/content/aeronav/sectional_files/Albuquerque_89.zip - Each ...
6
votes
2answers
1k views

Creating a multispectral image from scratch

I want to make a multispectral image from cero to do some tests on it. Something really simple like 5 completely uniform bands with salt and pepper noise on them or a square of different values at the ...
7
votes
1answer
2k views

How to get GDAL to create statistics for GTiff in Python

I regularly create my own GeoTIFF rasters with GDAL in Python, e.g.: from osgeo import gdal from numpy import random data = random.uniform(0, 10, (300, 200)) driver = gdal.GetDriverByName('GTiff') ds ...
7
votes
4answers
1k views

Are there GUI resources for gdal and ogr?

For those who are new to the programming side of GIS, I feel that a lot of great tools and resources are inacessible. I am interested in GUI based wizards for handling geoprocessing with libraries ...