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

8
votes
3answers
3k views

Make the nodata area of a resampled orthophoto overview white?

I have a set of orthophoto images which are each fully filled with data, but when placed together the coverage does not form a rectangle so there are nodata areas. In MapGuide, I need to be able to ...
7
votes
1answer
1k views

gdalwarp, cutline and postgis

I can not figure out how I directly can read a polygon into gdawarp's -cutline argument. My current approach is: ogr2ogr -f "ESRI Shapefile" mydata.shp PG:"user=myuser dbname=gisdb" -sql "select * ...
9
votes
7answers
2k views

how to overlay shapefile and raster?

I have a shapefile with polygons. And I have a global raster file. I want to overlay the shapefile's polygons onto the raster grid and calculate the mean raster value for each polygon. How can I do ...
8
votes
4answers
2k views

Performance of google map tile creation processes

I know that question is rather vague but please bear w/me. I'm trying to get an idea of what sort of product performance - specifically timing - people have seen for various methodologies they have ...
6
votes
1answer
729 views

Subsetting GeoTIFF with Python

I'm sub-setting a GeoTIFF with the GDAL Python binding and numpy. Essentially, I am providing a central location (coordinates of a flux tower) from which I produce a subsetted image. I then want to ...
6
votes
2answers
729 views

How to add GDAL to existing Python installation?

I would like to download and install GDAL for Python version 2.6 [MCS v.1500 32 bit(Intel)] on win32 that supports reading FileGDB's with Python. But I am not sure how to go about this. I found one ...
6
votes
3answers
1k views

GDAL and Geospatial PDF on Windows

GDAL 1.8 now supports reading GeospatialPDF, see pdf format description page. Using it depends on the poppler pdf library. What is the smoothest route to getting gdal and geospatial pdf working on ...
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 ...
4
votes
1answer
5k views

Transforming EPSG:3857 to EPSG:4326

I am new to gdal and have a simple question. I want to transform an image from OpenStreetMap projection to Nasa Blue Marble projection. What I understand is that OpenStreetMap projection is EPSG:3857 ...
13
votes
3answers
7k views

How do I change geotiff “no data” color to white/transparent rather than black?

I am preparing data for inclusion into a geonetwork node, where the maps are displayed via geoserver. The problem is that cells that have"no data" are displaying as black in the geotiff and I am ...
8
votes
2answers
952 views

Building FGDB support for GDAL 1.10 on Ubuntu

Because data.gc.ca is now distributing some of its data in FGDB format (example: Plant Hardiness Zones), I would like to be able to use it with gdal/QGIS. The compile/install is not going as planned, ...
7
votes
3answers
3k views

How to extract slope from topographic raster map?

I am working on a project for a machine learning class wherein I extract features from a topographic raster map and then classify the traversability of the terrain. One of the features I need to ...
6
votes
2answers
755 views

What's a good toolchain to reproject some PNGs in plate carre to UTM?

I have some PNGs produced from Canadian DEM data. They're 1201px by 1201px heightmaps. Each one represents one quarter of a degree latitude and one quarter of a degree longitude. But I want to work ...
4
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 ...
4
votes
1answer
642 views

Raster data array output flipped on x-axis using python/gdal?

I'm trying to create a raster using the python gdal libraries and I've gotten to the point where data is being output, but the output data is flipped on the origin point's x-axis. I know I must be ...
3
votes
1answer
111 views

Are there examples of high-level interfaces to NetCDF

The R raster package and GDAL both have independent wrappers around NetCDF-4* that treat an array variable as a "complete" dataset, i.e. they provide objects or interfaces that seamlessly give access ...
2
votes
1answer
3k views

Python GDAL: Save array as raster with projection from other file

I have an array of data, and for each datapoint I know the latitude and longitude. I'd like to save it as a GTiff with the same projection as other rasters I have. This is what I've tried so far, but ...
2
votes
1answer
350 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 ...
2
votes
2answers
933 views

GDAL Clipping (hack)

I am trying to use the python script from http://www.sparkgeo.com/labs/2010/07/07/gdal-clipping-hack/ to clip a raster based on many shapefiles. The script is using a mysql database an i would like to ...
1
vote
1answer
83 views

How do I convert a TIF to EPSG:3857

I'm trying to convert this TIF to EPSG:3857, but when I run: gdalwarp -of GTiff -s_srs epsg:4326 -t_srs epsg:3857 -co "tfw=yes" original.tif converted.tif I just get a black TIF do you know what I ...
1
vote
1answer
747 views

How to add a color table to a one band tiff using GDAL?

I have 1-band GeoTIFF file. The color interpretation for band is gray. I want a color table in order to transform my Col.tiff to Col.jpeg or Col.png. I tried putting a color table in this tiff via a ...
1
vote
2answers
868 views

Python - GDAL : Polygon to point shape file

I want to read all the points in a polygon shape-file and use their coordinates to make a new point shape file. then find the min and max of the X coordinates. So here is the code I wrote for the ...
1
vote
0answers
499 views

Topography: How to convert raster into vector layers?

(nb:This project is part of the #Wikipedia #wikimaps project) 1. Question: How to create vector topographic maps from raster image ? How to convert raster topographic image into closed vector ...
14
votes
1answer
939 views

How to rename field names in a shapefile from the commandline?

I need to rename the field names (attributes) in a shapefile. Is there an easy way to do this from the command line?
13
votes
3answers
7k views

ogr2ogr converting to shapefile - how to select feature types?

Shapefiles can only have one geometry type, but many other formats (kml, geojson) can have multiple types. When converting to shapefiles, is it possible to to tell ogr2ogr to create multiple ...
8
votes
6answers
927 views

How do I generate thumbnails images from lots of shapefiles?

A colleague and I recently released an Open Source project called Mapoteca which is a set of Python Scripts that integrates with a GDAL/FWTools installation allowing a full walk-through of directories ...
7
votes
2answers
571 views

Conflict between ArcPy and GDAL/OGR?

TL;DR I can't get an installation free version of GDAL/OGR to work from within ArcMap 10.0. I get an ImportError: DLL load failed on _mod = imp.load_module('_gdal', fp, pathname, description). ...
7
votes
2answers
567 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 ...
7
votes
2answers
3k views

How can I turn a shapefile into a mask and calculate the mean?

I have been using python to process huge arrays stored as netcdf files. I would like to calculate the mean of an area defined by a shapefile. I have just installed GDAL but if there are other tools I ...
7
votes
2answers
5k views

How do I convert affine coordinates to lat/lng?

I am extremely new to GIS. I'm using gdal to read in a landuse/landcover map and I need to pick out the lat/lng of certain land cover types to index into a different dataset which is expressed only ...
6
votes
3answers
923 views

How to convert factfinder2.census.gov map data to KML?

I've downloaded a map from http://factfinder2.census.gov/faces/tableservices/jsf/pages/productview.xhtml?pid=DEC_10_SF1_P1 (limited to San Francisco census tracts), and I'd like to convert it to KML ...
6
votes
1answer
1k views

What tile/tiling strategy should I use with GeoNode/GeoServer?

I've got a wicked GeoNode instance running, loaded with some basic vector data. I want to be able to serve our local-County aerial imagery as a basemap within GeoNode. I am thoroughly overwhelmed with ...
5
votes
2answers
614 views

how would one get the end points of a polyline?

I am attempting to write a script to get the end points of a series polylines, and then use those end points to create a polygon. I'm not sure which tools to begin to use on this project. I would ...
5
votes
3answers
3k views

How can I convert a ascii file to geotiff using Python?

I have a ascii raster format file. For example: ncols 480 nrows 450 xllcorner 378923 yllcorner 4072345 cellsize 30 nodata_value -32768 43 2 45 7 3 56 2 5 23 65 34 6 32 54 57 34 2 2 54 6 35 45 65 34 ...
5
votes
1answer
1k views

Python - OGR: Transform coordinates from meter to decimal degrees

I have a point in a shapefile. The shapefile is in a WGS_1984_Web_Mercator Projected Coordinate System. I want to get the coordinates of that point in decimal degrees with GDAL/OGR in Python. I am ...
5
votes
2answers
2k views

Where can the GDAL executables be found in a QGIS installation?

I run QGIS 1.8.0 Lisboa on a Windows 7 machine. Yesterday I attempted to install the TauDEM plugin using these instructions: http://lists.osgeo.org/pipermail/qgis-developer/2012-June/020807.html ...
5
votes
1answer
899 views

ESRI GDB Support in GDAL / ogr2ogr on Mac OS X 10.8

How do you incorporate support for ESRI's fgdb format into GDAL / ogr2ogr on Mac OS X 10.8?
5
votes
1answer
473 views

Where can I find GDAL bindings for Python 3.3?

I have been using GDAL 1.9.x on Python 2.7 and took the bindings from here. Is there a place to get GDAL bindings for Python 3.3 or is GDAL not officially supported in Python 3.3 yet?
5
votes
2answers
1k views

Converting Ordnance Survey raster maps to WGS84 webmap tiles

I would like to generate Google/Bing-like map tiles from Ordnance Survey's 1:25000 and 1:50000 raster maps, which are provided as 4000x4000 UK national grid tiles (GeoTIFF). A sample tile can be ...
5
votes
3answers
968 views

Reading palsar k&c 50 data in GDAL or other open source application

I posted this inquiry in the grass-user list. JAXA is providing free access to PALSAR 50m Orthorectified K & C Mosaic. According to the website, data are provided in: Data files (Raw ...
4
votes
3answers
503 views

Install gdal in CentOS without Root

I have been struggling to get python setup to do some image processing, so I really need the http://www.gdal.org/ GDAL libraries installed on CentOS 6.5. I want to install the package in a local ...
4
votes
1answer
551 views

How to find the distance to the nearest coastline from a land-based latitude/longitude point?

I'm completely new to GIS and unsure what I need to solve this problem: In the image above turquoise is actually land. Sea is white. I tried using the NASA Distance to the Nearest Coast data dump ...
4
votes
2answers
313 views

Converting shapefile to raster: Character attributes

I've got a shapefile that I would like to convert into a raster, but the trick is that the attribute I want a raster version of is character data. I'm familiar with geoprocessing using GDAL (in the ...
4
votes
1answer
450 views

Why is tiff different in epsg 3857 and epsg 900913 in gdal

When I transform tiff from 4326 to 3857 and from 4326 to 900913 in gdal, I get different result(when display in Qgis) eventhough these two projections(3857 and 900913) should be the same. What is ...
4
votes
2answers
2k views

how to for loop a folder to batch clip rasters by polygon using python and QGIS

I am using python and QGIS 2.0. I am trying to clip rasters in a folder by one polygon feature. It's the first time for me using (let's say) "PyQGIS", I was used to arcpy before. Anyway, I don't get ...
4
votes
1answer
552 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 ...
4
votes
2answers
2k views

ogr2ogr srs options: where is the well known definition determined?

In the ogr2ogr documentation it says that when using -a_srs srs_def: Srs_def can be a full WKT definition (hard to escape properly), or a well known definition (ie. EPSG:4326) or a file with a WKT ...
3
votes
1answer
491 views

calling gdal_merge.py into another python script running GDAL processes

Good Afternoon All, I am wanting to use gdal_merge.py to merge a series of .tif files prior to clipping the merged file to a shapefile boundary, but want to do so as part of another larger script ...
3
votes
1answer
125 views

Holes between imagery tiles projected using gdalwarp

I am having the following issue when reprojecting imagery tiles using gdalwarp. These are 4096x4096 imagery tiles, which I'm gdalwarp'ing from WGS84 to a State Plane projection. When reprojected, ...
3
votes
3answers
187 views

How to apply a specific Rendering to a Raster and export to JPEG?

We have a specific process which generate an interpolated single band 32-bit Float Raster in Erdas Imagine (.IMG) format. This process generates an image every hour. We wish to apply a specific ...