I think this is an important shortcoming: rs images most often have non-data values. In particular, once images are geometrically corrected, they are rotated and have non-data values in the edges. Applying window-based operation will produce artifacts if non-data values are present. It is worrying that this problem was raised by a user in 2010 and nobody actually reacted. If there were a wish list for future otb versions, non-data support would be my first one . Best, Agus
On Mon, Dec 15, 2014 at 5:55 PM, Julien Michel <[email protected]> wrote: > > Done. > > Julien > -------- Message transféré -------- Sujet : Re: Fwd: NoData values in > otb? Date : Mon, 15 Dec 2014 17:54:09 +0100 De : Agustin Lobo > <[email protected]> <[email protected]> Pour : Julien > Michel <[email protected]> <[email protected]> > > Thanks a lot for the fast answer. Do you mind sending it to the list > and we can discuss there? > Regards, > Agus > > On Mon, Dec 15, 2014 at 2:51 PM, Julien Michel <[email protected]> > <[email protected]> wrote: > > I am sorry I have been away for 2 weeks and I am catching up with my mails > > just today. There is currently no way to handle no-data values at the OTB > > level. Gdal is able to read/write a no-data property for datasets, but this > > does not cope well with the general pipeline model in OTB (and ITK), as we > > do not know what happen to no-data values when chaining several filters > > (e.g. resampling for instance). As a result this is considered as an > > application dependant parameter : some of our applications explicitely > > handle no data value (which must be provided by the user as a parameter). > > > > Regards, > > > > Julien > > > > Le 15/12/2014 10:21, Agustin Lobo a écrit : > > > >> Julien, > >> > >> Do you know the answer to this question? I've searched the doc and > >> cannot find anything related to it. > >> Instead, I've found another user asking the same question in 2010! and > >> not getting any answer either... > >> http://otb-users.37221.n3.nabble.com/Defining-null-values-td986404.html > >> This is also a concern for the band math. For example, is there a > >> function to check if a pixel is null or nodata? > >> > >> Thanks, > >> Agus > >> > >> ---------- Forwarded message ---------- > >> From: Agustin Lobo <[email protected]> <[email protected]> > > >> Date: Mon, Dec 15, 2014 at 10:16 AM > >> Subject: Fwd: NoData values in otb? > >> To: Agustin Lobo <[email protected]> <[email protected]> > >> > >> > >> ---------- Forwarded message ---------- > >> From: Agustin Lobo <[email protected]> <[email protected]> > >> Date: Fri, Nov 28, 2014 at 12:16 PM > >> Subject: NoData values in otb? > >> To: [email protected] > >> > >> > >> I edit my previous message, as I mean No Data rather than Null values > >> > >> On Thu, Nov 27, 2014 at 3:49 PM, Agustin Lobo <[email protected]> > >> <[email protected]> > >> wrote: > >>> > >>> is there a way to define a NoData value in the images so that those > >>> values > >>> are ignored in the computations? In the case of FineRegistration it looks > >>> like I get wrong results near the edges of the image because one of the > >>> images > >>> has null (which I represent as 0 in the tiff) values in one of the edges. > >>> Is defining the NoData value in the tiff sufficient? I guess not > >>> according to what I'm seeing, but i might be wrong. > >>> > >>> Agus > > > > > > > -- > -- > Check the OTB FAQ at > http://www.orfeo-toolbox.org/FAQ.html > > You received this message because you are subscribed to the Google > Groups "otb-users" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/otb-users?hl=en > --- > You received this message because you are subscribed to the Google Groups > "otb-users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- -- Check the OTB FAQ at http://www.orfeo-toolbox.org/FAQ.html You received this message because you are subscribed to the Google Groups "otb-users" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/otb-users?hl=en --- You received this message because you are subscribed to the Google Groups "otb-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
