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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3
votes
1answer
298 views

How does latitude of origin work in Mercator

I'm trying to make a coordinate transformation using GDAL/osr python bindings. I have a longitude an a latitude and I want to transform them into the mercator coordinates. So I define the mercator ...
7
votes
1answer
588 views

Can QGIS display GeoRSS in real time?

QGIS has the ability to display GeoRSS by following these steps: Click on "Add Vector Layer..." icon Make sure the Data Source is "File" and enter the GeoRSS URL with "/viscurl/" prefix on the ...
4
votes
1answer
836 views

Reproject script in Python with GDAL

I'm having a lot of trouble with GDAL. Besides just the at times lacking documentation, there seems to be little support in Python. Anyways this is just a batch reproject script that goes thusly: ...
1
vote
1answer
294 views

how to use gdal command inside php exec() function

I need to develop a webportal which will display the images generated by a GIS software package. I my development I need to run gdal command inside php exec() function. but I don't know how to do ...
0
votes
3answers
655 views

How to run GDAL command in php page? [duplicate]

I want to develop a webportal that will show the QGIS generated images on dynamic website. For this reason I need to run gdal_translate command inside php page. but I don't know is it possible or not. ...
3
votes
2answers
2k views

how to convert qgis generated tiff images into jpg/jpeg using gdal command line utilities?

I want to develop a web portal that will show the images dynamically produced by qgis . but qgis provided tiff images are too big in size and it is not possible to show it on website using image ...
4
votes
1answer
461 views

How to create tiles with points from MongoDB?

I have a (potentially) large data set stored in MongoDB. Each record is just lat, lon and some float-point value. Each pair of lat and lon is unique, but the whole set is not covering the Earth, there ...
2
votes
2answers
206 views

Issue converting DEM in ASCII with LO17 (apparent) projection

I'm a newbie where GIS is concerned, so please don't hesitate to point me to a manual. We've got DEM files without any projection information. One is called 000426_LO17_200M_BD16_25.ORT and contains ...
2
votes
1answer
238 views

only 1 tile visible in GE after gdal_translate -of KMLSUPEROVERLAY

I have a 3-band ASTER scene in any of several formats (PCIDISK, GeoTIFF, Imagine), already reprojected to the geographic coordinate system. I can view and manipulate the scene successfully in PCI ...
4
votes
3answers
2k views

'NoneType' object has no attribute

I am new to python geospatial programming. i ran the following script and got the corresponding error message >>> import osgeo >>> import osgeo.ogr >>> shapefile = ...
6
votes
8answers
4k views

Splitting shapefile into separate shapefiles for each feature?

I have a polyline shapefile with about 20 kinds of roads. I would like to know how can I create automatically a vector file for each one. I can use ArcGIS for Desktop, QGIS (or GDAL separately).
2
votes
3answers
990 views

Batch script converting and resampling orthophotos

I would like to convert more than 300 orthophotos produced at scale 1:8.000 with a pixel size of 0.8m X 0.8m from Ecw format to Tiff format and after resampling pixel values. My aim is to batch ...
14
votes
4answers
1k views

The best language to program with GDAL

I'm going to start to create programs to handle geographical data from a PostGIS server, and going to use GDAL. According to your experience, with the best language to program with it? I can program ...
6
votes
2answers
866 views

Big Satellite Image Processing

Im trying to run Mort Canty's http://mcanty.homepage.t-online.de/ Python iMAD implementation on bitemporal RapidEye Multispectral images. Which basically calculates the canonical correlation for the ...
3
votes
1answer
195 views

Problem with precision when convert from WKT to shapefile

I have a problem with converting from WKT to shapefile in pygdal. In wkt I have fields with precision (for example real 7.2). When I create a shapefile I have field numeric with no precision (numeric ...
2
votes
2answers
3k views

GDAL: Convert specific RGB (GeoTIFF) color to transparent

I have an RGB GeoTIFF file and I want to convert a specific RGB colour to transparent. I would like to use GDAL for doing this, but external Python scripts are also an option (though I haven't learned ...
7
votes
4answers
2k views

Open source software to merge large shape files

Some background: I have 2 polygon shape files with approximately 500,000 records each. The two files are identical in terms of field structure. Using ArcGIS 10.0 I can'nt merge these two files using ...
3
votes
1answer
596 views

Cell calculations; QGIS,GRASS,GDAL,SAGA

I recently asked a question about trying to calculate the slope over distance (manually) using QGIS, but then I came up with another way of solving the problem, but I would have to get some help for ...
0
votes
1answer
915 views

Trying to Install on MAC OS Lion and getting Python error message

Brand new to this and struggling to install QGIS on MAC OS X with Lion, I am not a techy - but noticed in the install read me that /usr/bin needs to be added to the GDAL.frameworks path. Failing to ...
3
votes
1answer
317 views

Adding metadata to a geographic gridded data-set and projecting it

I asked a question before that nobody answered...but I kind of figured it out myself. But I still remain with some things that I just don't seem to get right. Can anybody please find the time to help ...
2
votes
2answers
696 views

How to calculate a new raster based on nodata values from original raster, in QGIS?

I'm using the raster calculator from core in QGIS and I need to generate a new tif raster file (mask) from the nodata values of another tif raster file. I tried isnull(), but no luck. Any one can ...
4
votes
1answer
448 views

ArcGIS SP4 fails to open file geodatabases created with ogr2ogr

I've been using the new FileGDB support in gdal-1.9.0 to create file geodatabases that can be opened in ArcGIS. For example (I'm doing this all on one line, so I'm not certain this will run as ...
3
votes
1answer
727 views

Problems serving GeoTiff using GeoServer and ImageMosaic

Goal: I am trying to serve a large (1GB+) GeoTiff file using GeoServer and ImageMosaic. Process: iant have written a simple guide for this, which he proposed as an answer for a previous and similar ...
1
vote
1answer
2k views

UnboundLocalError: local variable 'x' referenced before assignment

I am trying to execute this code, import osgeo.ogr def findPoints(geometry, results): for i in range(geometry.GetPointCount()): x,y,z = geometry.GetPoint(i) if results['north'] == ...
5
votes
2answers
398 views

Adding noise to a raster

I want to add some fine-grained noise to a raster in an automated python process (i.e. I do not want to use Photoshop or GIMP). I looked at PIL, but unless I'm mistaken, it doesn't seem to have any ...
4
votes
2answers
404 views

gdalwarp in a bash shell for loop

I would like mask several images in bash shell, gdalwarp works for me as a simple single line command: gdalwarp -cutline mask.shp -cwhere 'kepnev="a.tif"' -crop_to_cutline a.tif a_masked.tif ...
1
vote
2answers
142 views

can't generate/display signed float values using python/gdal

I'm trying to create a raster with signed float values as the pixel values and display the results in MapWindow on windows. What is the proper gdal band type to use? I've tried both gdal.GDT_Byte ...
3
votes
1answer
454 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
157 views

Change ellipsoid reference for altitude in a DEM

I have DEM data stored as RGF93 (Lambert-93) for lat/lon and NGF-IGN69 for altitude. I'm trying to change the reference ellipsoid for the elevation data (ultimately to NTF, but WGS84 would be fine to ...
10
votes
2answers
2k views

How to get FGDB support in GDAL 1.9 without compiling?

I was hoping that I could use the 'master' (nightly-build) version of QGIS to get fgdb support without compiliing (I'm not a developer and frankly have wasted days of productive time trying to get ...
2
votes
1answer
558 views

Cannot replicate gdaltransform example

In the description of gdaltransform this example is given: gdaltransform -s_srs EPSG:28992 -t_srs EPSG:31370 177502 311865 Produces the following output in meters in the "Belge 1972 / Belgian ...
1
vote
1answer
260 views

Is there any support for Rasterlite in the Android QGIS?

Is there any support for Rasterlite databases in the Android port of QGIS? I have tried adding a raster layer as I would on desktop QGIS but there are fewer GDAL file formats listed. Is this ...
7
votes
1answer
414 views

What are the rules that the Gdal rasterize function follows to allocate a value to a cell?

How does the rasterize tool decide which value to represent when a cell covers an area which inclueds different values? I need it in this case for polygons but would like to know for lines and points ...
1
vote
2answers
1k views

How to create proper PostGIS points out of GRIB2 file?

I'm trying to load NCEP NOAA weather data from GRIB2 format into PostGIS and then visualize it using QGIS etc. I'm using wgrib2 library to convert the GRIB2 data to csv first. wgrib2 -match ...
4
votes
2answers
1k views

How to style a GeoTIFF in Tilemill?

I'm trying to create a "heatmap" style visualization from a number of geopoints and values associated with them. I have been following along with this blog post. I've got a CSV file of points like ...
0
votes
0answers
253 views

QGIS GDAL integration of new version [duplicate]

Somewhere else on this forum ("How to access file geodatabase in Qgis?") someone asked how to access data from an Esri file geodatabase in Quantum GIS? One of the answers pointed to ...
4
votes
2answers
4k views

How to install stable GDAL on Ubuntu 11.10?

I am trying to install the stable ubuntu package from here https://launchpad.net/~ubuntugis/+archive/ppa/+packages on my ubuntu 11.10 server I have added the ubuntugis stable repository to server's ...
5
votes
4answers
1k views

Create a ground overlay kml from georeferenced raster

I have a world georeferenced raster (5m resolution, ~4000 x 4000 pixels) that I would like to display in google earth. I am looking for a simple and effective way to generate this kml file. Using ...
1
vote
3answers
547 views

Geoserver - ImagePyramid plugin problem

I have a huge Geotiff file , and i've tiled it .. I've created the tiles using gdal_retile.py tool , but i'm getting the following error from Geoserver while linking the layer with the tiles folder : ...
3
votes
2answers
538 views

Can I create blended images with GDAL command line utilities?

I've written a program in Python with GDAL bindings that generates a single band georeferenced GeoTIFF as output. From there I use the GDAL commandline tool gdaldem to colorize that image to ...
9
votes
7answers
2k views

How to add field with filename when merging shapefiles with ogr2ogr?

I'm merging some shapefiles and I had some problems doing so inside QGIS, so i'm using ogr2ogr directly. I'm doing this (in a batch): ogr2ogr -overwrite %destination% %n1% ogr2ogr -update -append ...
7
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 ...
0
votes
1answer
196 views

requesting tiles without using xml file (gdal - c++)

i have been able to request a specific tile with my xml through gdal lib. However, is there is another way of requesting the tiles from a web server without using xml ? i wanna do it directly through ...
2
votes
1answer
478 views

How do I change a raster's geotransform with GDAL?

I'm trying to use GDAL to set the geotransform of a new raster that I've created by following the steps outlined in the GDAL API Tutorial. # create the new dataset driver = ...
8
votes
3answers
9k views

How can I install gdal 1.9.0 on my linux ubuntu server 10.04

apt-get install python-gdal installs version 1.6.0 and this is already installed. I would like to install the 1.9.0 version. Do I have to de-install 1.6.0 first and then compile manually or is there ...
2
votes
1answer
229 views

Why doesn't Gdaladdo make the background transparent?

I noticed that the backgrounds of my geotiffs were transparent up until I started added overviews with gdaladdo. Is there a way to combat this?`
3
votes
1answer
627 views

How can I merge geotiffs with a vrt file?

I have heard that I can use a vrt file to merge mulitple geotiffs into one? what is the syntax? gdal_tranlsate -of VRT file1.tif file2.tif file2.tif Something like this?
1
vote
1answer
323 views

GDAL Brightness RGB Contrast Gamma Saturation

I've not had much experience with modifying imagery, I've recently been playing with GDAL for some batch processing of geo-referenced images, I've been supplied with some imagery in ECW format that is ...
1
vote
2answers
2k views

Georeferencing an image in C# with GDAL

I want to upload a jpeg or some raster image into a C# form and then on entering the latitude and longitudes I need to be able to create an GEOTIFF file of the same image. How can this be done in ...
0
votes
1answer
2k views

How can I convert SRTM data to DEM or DTED?

i am working on a project which is not commercial and i need some digital elevation data for visualization. in net i have found a link and i have downloaded .asc data from following link.. SRTM Data ...