[gdal-dev] Re: patch for ISIS2 driver

[Ludovic Mercier]

Hi,

Le 06/12/2010 20:50, Trent M Hare a écrit :
> It would also make sense to
> merge the PDS and ISIS2 code set however there are subtitle differences
> in both formats that we must be careful of.
I have an existing code for this (only IMAGE tag), and in my patch i 
have prepare two function to manage IMAGE tag and SPECTRAL_QUBE tag.
See Open() function in patch.

> Before we can incorporate your changes into GDAL, I would like to see
> projection export support implemented also. The main reason for these
> readers was to help propagate the projection, so I would want to see
> this working both directions. I will see where it stands and if I can
> help.
I not use projection at this time but i'm looking for this.

> I'm not sure how to implement "create_copy" so we might need help
> from the GDAL team.
If i have the time i look this also...

> Let me check out your patch and test some images. If all looks good we
> ask the GDAL team to also help incorporate your patch. Also there is
> another PDS fix that needs to be incorporated. Maybe you might have time
> to see if it would be a quick fix since you have been working wit the
> code recently (please see issue below). If you don't have time please
> let me know.
 > I am also curious how you managed to support ISIS2 side
> planes? This capability was removed from ISIS3 due to lack of use and
> complexity.
In my case for this time my algorithm not use backplane but image have 
backplane or side-plane. Also the patch read qube data and remove 
backplane information. But i think about this to integrate backplane 
information :
two possibilities :
* write another file with information
* keep backplane information with metadata
I think if we can implement the two possibilities will be very interesting.
>
> Thanks again for your willingness to share your improvements. Just out
> of curiosity - what facility are you working with?

I'm not sure to if I understand correctly your question (i am not very 
good in English sorry :( )
But i use gdal with the library OTB (http://www.orfeo-toolbox.org) to 
create algorithms for working on hyperspectral data from spacecraft 
(planetary mission) : OMEGA, CRISM, VIRTIS, etc.


Regards

Ludovic

Response to comment :
> /i have a patch for gdal 1.7.3 to improve isis2 driver./
> /* writing functionality for QUBE object //-/ again I would like to see
> an attempt at supporting projections also - I will help.
See first part of this message
> /* grab null value /- What does this mean as support for a single NULL
> value was there? Does this address the fact that all ISIS2, PDS, and
> ISIS3 can support multiple NULL values?
Multiple null value is a problem, i think about this : thread with Frank 
with title "several No data value"
> /* can read qube with back plane, side plane and bottom plane /- great
> again sI will need to see how you supported side/bottom planes. Do you
> make a new file?
See first part of this message
> /* can read a file with label detached or attached. -/ I thought this
> was already implemented? Maybe there were some fixes though./ /
Originally my patch worked with gdal 1.6.3 there were some problem with 
this.