1
vote
2answers
33 views

Error getting ESRI Shapefile driver OGR in C++

I am unable to create an OGR Layer using the C++ API. I have followed the documentation at this link exactly http://www.gdal.org/ogr_apitut.html I get an error trying to get the shapefile driver. Any ...
0
votes
1answer
29 views

going from hillshade to percent shaded (gdaldem)

I assumed hillshades output percent shaded (scaled to 255) at the given azimuth and altitude but this is incorrect. A flat raster at 80 degrees altitude has a maximum value of 251 instead of 255. How ...
1
vote
0answers
17 views

Rendering a geotiff block with gdal and gdk-pixbuf - Some flaws in the result

I currently try to render a geotiff file with GTKmm\GDKmm (gdk-pixbuf). The file is a tiled geotiff with a block size of 256*256 and three rasterbands. The shortened gdalinfo output is: Driver: ...
1
vote
0answers
42 views

Correct way to extract pixel data using GDAL. Current method gives repeated but changing value.

I am trying to open a spectral file and move bands of data from GDAL to OpenCV's Mat data structures. As of now I am just trying to make sure that I can correctly access each band using GDAL and pull ...
0
votes
0answers
44 views

gdal read whole geotif band into vector

i have another c++ GDAL question. I try to read alle elevation data out of an GeoTiff file into a c++ vector so that i can get elevation at x,y like this: vector[x][y]. I also like to use this data to ...
0
votes
1answer
34 views

gdal_contour transparent contour as png

I started using the GDAL Library in a c++ project. It is a great library, but I am a bit stuck right now with different aspects of it. What is the best way to use gdal_contour in my c++ programm? ...
1
vote
0answers
66 views

GDAL C/C++ API and filtered pyramid tile generation

I have been tasked with adding functionality to an existing C++ developed toolset whereby a source dataset (typically a single GeoTIFF) needs to be split into tiles at various resolutions ('zoom' ...
1
vote
2answers
238 views

combine raster with another raster mask file - gdal

I have 2 rasters in GeoTiff format. One has all of the land and water and the other is a mask file that shows either 0 for water or 1 for land. I basically want my output to just have the land values ...
0
votes
0answers
80 views

Using GDAL to link to a TMS

I currently have a C++ application that will consume a WFS using gdal. It determines if the WFS layer is points or polygons then adds stores them in an appropriate object that is later used to ...
1
vote
2answers
96 views

Difference between OGRGeometry and Geometry in C++ and python

According to the documentation, there is a python version of OGRGeometry's C++ class (http://www.gdal.org/ogr/classOGRGeometry.html) which is http://gdal.org/python/osgeo.ogr.Geometry-class.html ...
1
vote
1answer
66 views

OGRFeature::DestroyFeature fails

I am using OGR to read features from a shape file; when the feature is destroyed I am getting an error 0xC0000005: Access violation reading location 0xffffffffffffffff. This secton of the code looks ...
0
votes
1answer
405 views

GDAL RasterIO grabbing memory

I have written an application in c++ to read LiDAR files and convert to various rasters using GDAL; this worked very well on small scale tests (47 LAS files) however, when used on a live task the ...
1
vote
2answers
156 views

will ogr get coordinates in geographic coordinate system or projected coordinate system when using getPoint(int,OGRPoint*)

Consider the code that I have written in the stackoverflow question How to extract vertexes of geometries in ESRI shapefiles using ogr library with c++, I have used the code to show shapefiles on an ...
-3
votes
1answer
77 views

How can I use ogrinfo to reach information anout a .shp?

How can I use ogrinfo? where should I write it? In the visual studio's command prompt or somewhere else? Can you make some examples? when I use ogrinfo in the windows or visual studio's command ...
0
votes
0answers
164 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 ...
1
vote
2answers
233 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
269 views

Link GDAL to consume a WFS

Im using a WFS that is openly available as a demo from mapserver's website http://demo.mapserver.org/cgi-bin/wfs?SERVICE=WFS&VERSION=1.0.0&REQUEST=GetCapabilities And now i want to make a ...
2
votes
1answer
380 views

Using GDAL to connect to a WFS

I'm trying to connect to a wfs using GDAL, from reading some of the (fairly sparse) documentation on this i have found that this is possible if GDAL is compiled with the correct drivers (Curl, ...
2
votes
0answers
348 views

Completely new to GDAL: please help me with the best way to study it

This is the first time that I post here so pardon me for asking such a beginner question. I'm completely new to GDAL and I'm going to use it to work with satellite images, DEMs, etc. I have some ...
0
votes
0answers
47 views

How to retrieve PROJECTION value for a map?

I am trying to read the Projection from Geotiff/shape file, using gdal 1.9.0 by the following command in the command line... gdalinfo.exe -proj4 map-path but its retuning empty string for ...
3
votes
0answers
54 views

How do I get the domain from an OGRSpatialReference?

I would like to know what the projected bounds are for a spatial reference using OGRSpatialReference. Is there some way to use the GetProjParm method to get this information? An example of what ...
2
votes
1answer
113 views

Using the C++ GDAL API how do I set the GDAL_DATA path?

If I want to change the directory of the GDAL_DATA path or point to a different version of a csv file for EPSG numbers how do I do that using the C++ API?
3
votes
2answers
616 views

circle detection on binary image

My image is gray scale image which i have converted to binary by smoothing and then edge detection method. Now i want to place the circle /ellipse on edge detected. I don't know how to proceed ...
1
vote
0answers
161 views

using GDAL/OGR (faster)

Eventually, I was able to get the GDAL installed and compiled correctly using Visual C++ 2010. I even tested some of its methods on some geo-referenced raster files, and it looks like that all is ...
2
votes
1answer
92 views

Create ERDAS IMG Statistics using GDAL C++ API?

I want to create very many ERDAS .img files using GDAL under C++. I don't want to have to process them all in ArcMap to create statistics for them (mainly because ArcMap fumbles when calculating ...
0
votes
1answer
391 views

Most optimal algorithm for contour correctness?

Am creating an app which correctly calculates contours from a DEM file or any height-map given to it. The correctness of the contour holding the most importance, since a person viewing the contours ...
1
vote
0answers
101 views

OSGB36 referenced PNG to Google Earth

I am creating a PNG that is referenced to the OSGB36 datum (1 pixel per 50m easting/northing that is colored according to the result of some calculation code) I want to display this on Google Earth ...
1
vote
3answers
1k views

How to subset raster image using gdal?

I have read pixel values of an raster image using GDAL libraries in visual studio 2010(vc++). Now I have to crop the image (subset) according to the grid given in shape file. I have got a code for ...
5
votes
1answer
403 views

Slow FileGDB Performance in GDAL

I am attempting to write many ASPRS LAS point files into an ESRI File Geodatabase using my compilation of GDAL 1.9.2. The FileGDB driver for GDAL/OGR appears to be incredibly slow when writing large ...
1
vote
0answers
164 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 ...
1
vote
3answers
493 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 ...
0
votes
3answers
365 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 ...
0
votes
1answer
202 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 ...