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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5
votes
3answers
990 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
573 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
611 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
352 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
490 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
1k 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
1k views

processing MODIS hdf files with gdal

I'm trying to open an MODIS file (hdf format) with gdal in a python script under windows OS. I use the HDF4 driver, as read at http://www.gdal.org/frmt_hdf4.html. But when I run it I got this error ...
4
votes
1answer
366 views

How to convert a png with known bounds from Plate Carree to Mercator with GDAL

I have a png image that shows the region defined by the geo bounds UpperLat, LeftLon, BottomLat, RightLon (in degrees & -ve for West Lon and South Lat) in Plate Carree EPSG:4326. I want to convert ...
4
votes
1answer
586 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
2answers
625 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
139 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
194 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 ...
3
votes
3answers
229 views

Gdal: how to get the max and min altitudes of my topographic raster?

Given a .tiff topographic raster image. How to get the altitudes of the highest and lowest point/pixel ?
3
votes
1answer
455 views

Clip and copy files to same directory structure using OGR/GDAL with Python

We need to clip all our data (many TB) by a new boundary and save it while maintaining the same data structure. I want to use OGR/GDAL as the data is in shp/tab/kml/geoTif/ecw etc. I can find the ...
3
votes
1answer
372 views

gdal2tiles.py problem - creating mini tiles

I have a similar problem to the issue posted here (gdal2tiles problem). I have 80 GeoTIFFs (4000x4000) with EPSG:27700 projection embedded and TFW and PRJ files. These I have built into a virtual ...
3
votes
3answers
2k views

GDAL 1.10 ogr2ogr OSM “Unable to open datasource”

I have a problem with ogr2ogr and osm file. I install from source (on Ubuntu 12.04.2 LTS) newest GDAL libary and OGR still can't read osm files. gdal-config --version 1.10.0 ogr2ogr --version GDAL ...
3
votes
3answers
2k views

gdal2tiles.py generates wrong tiles / MapTiler the right ones

I'm trying to generate tiles with gdal2tiles.py and the resulting tiles are stored as 18/132639/164219. If I do the same thing with MapTiler (the GUI variant of gdal2tiles) the tile result is ...
3
votes
1answer
258 views

st_clip and gdal_translate: “Error browsing database for PostGIS Raster properties” - Why?

Im using shell-script, postgis2.0 and gdal for trying to clip raster apart, using an overlapping raster and a the_geom-object. At first I create a view to clip the overlapping part of the raster. It ...
3
votes
1answer
129 views

How to test if two GDAL datasets are in the same projection?

I'm attemping to write a funciton to test if a list of datasets are in the same projection. Naively, I thought I could test the text of WKTs, but that does not work in the following case: ...
3
votes
5answers
1k views

Batch processing DEM rasters in QGIS/GDAL

I am attempting to add relief shading to map using .asc raster files, following this tutorial. It works well, but I have only tried it on single tile of raster data which is 20x20km. I want to ...
3
votes
3answers
769 views

DXF to georeferenced SHP

I know how to set projection and georeference bounds of scanned TIFF file, by using gdal, but I don't know how to do the same for vector file. For example I georeferenced TIFF file by using this ...
3
votes
1answer
1k 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 ...
3
votes
1answer
487 views

Want to use GDAL in Arc10 toolbox via subprocess call

I'm attempting to launch a version Python 2.5 that supports GDAL from an ArcGIS10 toolbox script. I'm doing this because I'm having loads of trouble importing the GDAL library directly into Arc, and ...
2
votes
1answer
24 views

How to average gdal_hillshades?

For some unknow reason, my average of 3 hillshades is very dark : gdaldem hillshade input.tif hillshades_C.tmp.tif -s 111120 -z 5 -az 315 -alt 60 -compute_edges gdaldem hillshade input.tif ...
2
votes
3answers
137 views

Read HDF4 data using python

I am now working with VIIRS/NPP Active Fires by using python gdal. But I cannot read the data inside the files. Filename = "NPP_AVAF_L2.A2012019.0600.P1_03110.2014057125956.hdf" Here is some ...
2
votes
1answer
394 views

Convert GeoPDF with GDAL

I'm attempting to convert a USGS US Topo GeoPDF in Windows. I'm using GDAL 1.11.1. My initial attempts were with this Python script, which automates the process by feeding a command to the Windows ...
2
votes
1answer
180 views

QGIS show gdal_polygonized file in EPSG:54004 instead of EPSG:3857

I am polygonizing a TIFF with the gdal_polygonize.py and the resulting Shape is shown in QGIS in the wrong projection - EPSG:54004 instead of EPSG:3857. I have a TIFF in EPSG:3857 and polygonize it ...
2
votes
0answers
334 views

Merge overlapping DEMs with irregular boundaries

I have a 10m DEM covering part of a state, a 20m DEM covering the whole state, and a 90m DEM covering the whole country. How can I merge them together, getting the best quality available in each area? ...
2
votes
1answer
973 views

GDAL bindings problem with ArcMap 10.1 Python tool

I'm really getting mad with this. ArcGIS sometimes can be so just...irritating! Forgive me if this question is by any means duplicating this one or similar ones, but I really can't find my way out of ...
2
votes
1answer
662 views

Converting CIB data to Google Tiles with GDAL

I'm trying to convert CIB map data into Google compatible Tiles through the following process (in Linux, GDAL compiled from source): gdalbuildvrt data.vrt A.TOC gdal_translate -of VRT -expand rgba ...
2
votes
1answer
2k views

What are the appropriate parameters to convert .asc file to geotiff using gdal_translate?

My starting file of interest is an ASC file with the following gdalinfo Driver: AAIGrid/Arc/Info ASCII Grid Files: sd_1_3_110805.asc Size is 11880, 9720 Coordinate System is `' Origin = ...
1
vote
0answers
83 views

GeoDjango: AttributeError: function 'GDALAllRegister' not found [closed]

Im trying to get started with GeoDjango. I am using this https://docs.djangoproject.com/en/1.8/ref/contrib/gis/tutorial/ tutorial. When I run "python manage.py migrate" This error occur: ...
1
vote
1answer
258 views

Changing color of raster images based on their data values - gdal

Let's say I have 1 band raster images with Gray Color Interpretation and I want to change their color based on their data values. Data values -1, will be Blue, -0.5 will be Light Blue, 0 will be ...
1
vote
1answer
390 views

using GDAL/python to stack georeferenced images of different sizes

I am in the process of porting a code I wrote in IDL (interactive data language) to python but am running into a bit of a problem that I am hoping someone can help me with. The code goes like this: ...
1
vote
2answers
334 views

GDAL and Python - Don't print GDAL Error messages

According to the GDAL Python Documentation, GDAL functions do not raise exceptions or errors but do print errors to the console via stdout and stderr. I have some code in my script that calls ...
1
vote
2answers
414 views

Gdal: How iterate through all pixels of a raster image?

Given a topographic raster image. How to iterate through all pixels of this raster image ? Solution preferably with gdal, in console. Some other libraries/script could be installed. Related: ...
1
vote
1answer
325 views

Qgis - raster values become integer when Polygonizing

When using the GDAL plugin, "Polygonize (raster to vector)" any values in the resulting vector layer is truncated to integer. I have a raster showing windspeeds in squares of 500*500 meters, in the ...
1
vote
2answers
364 views

Convert .tiff data to bitmap just when rendering and at runtime by visualC++ code

I need to convert a .tiff image to a bitmap one without saving the bitmap. I know that I should use GDAL_translate but because I'm new, this function's interface is a little complicated for me. Could ...
1
vote
1answer
517 views

How to extract a WCS layer with gdal_translate?

There is a certain WCS layer that I'd like to save it to my local computer for analysis. According to GDAL WCS driver draft: "Accessing a WCS server is accomplished by creating a local service ...
1
vote
2answers
459 views

How to produce a mean raster file based on other raster files? [duplicate]

Possible Duplicate: Tools to flatten the jp2 to a single band (average the bands)? I have a number of raster files from a same area, that coordinates of corresponding pixels perfectly match ...
1
vote
2answers
641 views

Proper gdaltrasform syntax to transform a list of coordinates?

this is probably a very simple question, but I'm very new to GIS so I just need one last nudge. I've got a sense of the Linux utility gdaltransform and I am feeding it coordinate pairs in ...
1
vote
0answers
607 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 ...
1
vote
2answers
2k views

Get extent of Georeferenced Rasters in Python and output to polygon shapefile

I would like to create a shape file containing the extents of each of the rasters in a directory. Is it possible to capture the extent of a raster using Python? I have tried ...
0
votes
1answer
47 views

Facing a problem when re-projecting a file?

I am trying to re-project from Equi-rectangular. The file is provided as HDF5. I wonder why half of the map is not projected correctly. gdal_translate -of "ENVI" -gcp 0 0 0 90 -gcp 1440 0 360 90 -gcp ...
0
votes
0answers
301 views

How to read vector datasets using GDAL library

Up to now, I have used GDAL in order to read raster information and geotiffs and show them with the help of OpenGL. Now I have a vector dataset, and by that, I mean I have the files with types: DBF ...
0
votes
1answer
241 views

Gdal_polygonize: How to filter pixels above a given value (elevation)?

Given a topographic GIS raster of one country: Given an elevation threshold n = 50 (meters) How to polygonize pixels when z >= n ? gdal_polygonize.py is not clear on this point. It states This ...
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 ...
9
votes
2answers
816 views

Python, GDAL and building raster attribute tables

I have an integer raster for which I would like to build a raster attribute table using Python and GDAL. I can create a GDAL raster attribute table in Python as follows: >>> rat = ...
8
votes
1answer
770 views

How to add a band to an existing GeoTiff using GDAL?

This seems like it should be straightforward but I can't for the life of me figure it out. Given an existing GeoTiff containing a single band, how can you add another band to that GeoTiff? Is the ...