[gdal-dev] "Syncing" two rasters together...

[Tim Keitt]

On Thu, Mar 27, 2014 at 4:26 PM, Jonathan Greenberg <jgrn at illinois.edu>wrote:

> GDALers:
>
> What is the most efficient way, given a "reference raster", and an
> arbitrary raster (we'll call it "unsynced") synced together to allow
> them to be stacked: the output of this should be the unsynced raster
> with the same number of rows, columns, pixel size, upper left
> coordinates, and projection as the reference raster.
>
> Here are the assumptions:
> - both rasters already have the same pixel size and projection, but
> the offset of the upper left coordinate may not be "perfect"
>
> - for each pixel location defined by the reference raster, the output
> should have the closest (nearest neighbor) pixel from the unsynced
> raster.  It should have some NA value in regions where the reference
> and unsynced do not overlap.
>
> Thoughts?  The application of this would be e.g. taking a set of
> Landsat images from different time periods (each image has slightly
> different numbers of rows and columns), and stacking them together to
> perform time series analysis.
>

If I read right you are trying to estimate the x,y offset error in one
image. You can assign GCPs by picking identical pixels in each image and
then warp one of them to the other. OSSIM has some capability for image
matching I believe. If you convolve the two images, you should get an
impulse at the correct offset, but this is tricky in practice. Panorama
software may be able to compute the exact matching of the images.

THK


>
> Cheers!
>
> --j
>
> --
> Jonathan A. Greenberg, PhD
> Assistant Professor
> Global Environmental Analysis and Remote Sensing (GEARS) Laboratory
> Department of Geography and Geographic Information Science
> University of Illinois at Urbana-Champaign
> 259 Computing Applications Building, MC-150
> 605 East Springfield Avenue
> Champaign, IL  61820-6371
> Phone: 217-300-1924
> http://www.geog.illinois.edu/~jgrn/
> AIM: jgrn307, MSN: jgrn307 at hotmail.com, Gchat: jgrn307, Skype: jgrn3007
> _______________________________________________
> gdal-dev mailing list
> gdal-dev at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/gdal-dev
>



-- 
http://www.keittlab.org/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/gdal-dev/attachments/20140327/85b7d733/attachment.html>