Hi, > I need to find NDVI and other vegetation indices and then find changes > in time with tif images. > > I've been using Geotools for this. Took 2 tiff images, then using QGis > I changed them to PNG because original ones are huge. Then taking > those 2 PNG I created NDVI image using JAI. The problem is that I > couldn't show this file with Geotools. You can look at the code here: That code creates a TIFF with floating point pixels, which can be loaded/viewed with DisplayNBImage since DisplayNBImage internally creates a byte-based surrogate version of the floating-point image. If your purpose is just to display the image why not create a byte-based one?
> > In fact, proposing non-Jai way of the same thing would be awesome. > If you don't mind having a byte image that should be simple. Open both images, declare a matrix of the appropriate size of type float, calculate the NDVI for each pixel, create a temporary byte image and populate it with the values from the matrix, properly normalized. Some steps for this are on http://www.lac.inpe.br/JIPCookbook/1200-create-gl.jsp#imageanddatamanipulationcreatinggraylevelimages . Two caveats: I am not sure if plain Java have readers for TIFF images (in case your original images are TIFFs) and the original NDVI values will be of course gone -- not an issue for visualization/comparison. hope it helps Rafael ------------------------------------------------------------------------------ Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft MVPs and experts. ON SALE this month only -- learn more at: http://p.sf.net/sfu/learnmore_122712 _______________________________________________ GeoTools-GT2-Users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
