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 ...

learn more… | top users | synonyms

4
votes
1answer
472 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
239 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
421 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
442 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 ...
1
vote
0answers
533 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
424 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
457 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
179 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
978 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
951 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 ...
5
votes
2answers
442 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
583 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
512 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
442 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
611 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
671 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
1k 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
396 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
154 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
770 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
300 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 ...
12
votes
10answers
8k views

Python GDAL package missing header file when installing via pip

I asked this question on Stack Overflow before I realised this site existed. As this site it more appropriate, I'll ask it here too. I'm trying to install gdal from pip pip install gdal inside a ...
1
vote
1answer
206 views

gdal_retile - Out of range band requested

I'm using gdal_retile to create ImagePyramid from a set of GeoTIFF images. I'm using following command: gdal_retile.py -v -r bilinear -levels 8 -ps 2048 2048 -co "TILED=YES" -co "COMPRESS=JPEG" ...
5
votes
2answers
780 views

GDAL - Perform Simple Least Cost Path Analysis

I am investigating methods to perform a simple least cost path analysis with gdal. By simple, I mean using the slope of a dem as the only cost factor. I would prefer to do using the python or .net ...
2
votes
1answer
2k views

Convert area from square meters to degrees globally

I have a global raster file with 3600x1800 pixels. I don't have any information about the projection used. The raster contains one band with a quantity with the unit "per square meter". How can I ...
0
votes
3answers
409 views

raster data retrieval from postgis using c++

I have raster data in a postgis server (I am able to see it in qgis). When I retrieve it and form gtiff image out of it using gdal, the generated image is not correct (there is a coloring problem). I ...
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 ...
5
votes
2answers
538 views

Tiling high resolution image using GDAL tools

I have a .tif image that I georeferenced using QGIS utility. It was originally in UTM with NAD83 as datum. I need to make tiles out of it and get a kml file to overlay onto google earth. Here's how I ...
1
vote
1answer
110 views

Can I avoid runtime raster interpolation by creating an image pyramid to match the zoom scales?

For image quality and performance reasons, it would be best to perform interpolation of my large TIFF image of the world (10GB) beforehand to all the zoom scales I need to display at so that MapGuide ...
3
votes
2answers
366 views

Eliminate small polygons from shapefile

I downloaded GTOPO30 *.DEM files, and extracted a contour line at 2000m altitude using gdal_contour. In the resulting shapefile, I have many small polygons in areas where the altitude is close to that ...
1
vote
1answer
414 views

GDAL: Raster Intersection

I have two raster layers. (A) is state-sized, 30m. (B) is county-sized, 3m. I'd like to get a new raster (C) which is the part of (A) which coincides with (B), preferably scaled to the same ...
3
votes
1answer
1k views

How to use gdal_contour in QGIS Python console?

Is there a way to use the gdal_contour utility with-in the python console of qgis ? Thank you
2
votes
1answer
794 views

Filtering a raster by pixel value ? (Qgis)

I have downloaded Globcover data in GeoTIFF format. I want to create a new grid which only has values where the Globcover data (the only band in the TIF file) has one certain value (==190). Can I do ...
10
votes
1answer
1k views

Understanding the Map Tile creation properties

I am trying to create a tile base map. I have an image that I want to create the tile from and I am using GDAL. I managed to create the tiles but when I view the result it seems that the tiled map ...
3
votes
1answer
701 views

how do I get the “outer mantle” of a polygon shape file? (without joining all the polygons)

I am interested in finding all the vertices of all polygons which are not on the inside the most outer polygoin that can be formed in a shape file: Here is how I get all the vertices: def ...
5
votes
2answers
3k views

How to georeference using GDAL tools?

I have a .tiff image that I am trying to overlay in google earth. For that I require to georeference it first. The image projection is UTM with NAD83 as datum. I know the lat/long of the four corners ...
7
votes
2answers
7k views

ECW for QGIS 1.8 in Ubuntu 12.04

I have followed various online help guides on how to make ecw for QGIS 1.8 work in Ubuntu 12.04. I had it all working in Ubuntu 10.04 but since migration to 12.04 no such luck. Is there a guide that ...
10
votes
1answer
465 views

OGR/GDAL threading results in low core utilization

I'm trying to process some raster data using ogr/gdal and I can't seem to get full utilization of all the cores on my machine. When I only run the process on a single core, I get 100% utilization of ...
2
votes
1answer
457 views

How to add GDAL Programs folder to ~/.bash_profile

I have recently installed on Mac OS X Lion 10.7.4 the GDAL Framework 1.9 with Python bindings from [http://www.kyngchaos.com/software:frameworks][1]. I need to add the following Programs folder to my ...
1
vote
1answer
985 views

TMS format specification

I want to convert large map file to tms format. how directory structure, zoom levels , tile size, xml file creation have to be dealt with. Please point to the relevant docs. And is there any gdal c++ ...
4
votes
1answer
791 views

GDAL: How to build an image pyramid starting from the base

Normally I would create an Image Pyramid using gdal_retile.py on one large image or a set of large images. I want to do the opposite. I have all the zoomed in tiles on the base level and I want to ...
5
votes
1answer
369 views

Mosaicing indexed colour rasters with independent colour tables

I have a large number of single band rasters that are colour indexed TIF files. I want to mosaic them using GDAL (or similar non-proprietary software with a Python API I can call as part of a bigger ...
3
votes
1answer
746 views

Serving 4 band GeoTIFF in GeoServer 2.1.4

I have an uncompressed GeoTIFF file (figure 1) with the following band information: Image Structure Metadata: INTERLEAVE=PIXEL Band 1 Block=5000x1 Type=Byte, ColorInterp=Red Band 2 Block=5000x1 ...