[Gdal-dev] JP2KAK

[Frank Warmerdam]

Mark Overmeer wrote:
> It wonders me that the file is reopened in the first place (why?).  

Mark,

The GDALCreateCopy() function returns a handle to the opened dataset
created, but many "create copy" functions have to fetch such an object
by calling the generic GDALOpen() function when they are done writing
the dataset.  You can think of this as an artifact of the internal API
organization.

 > And then,
> weird that the -of flag is ignored.  Although that did accidentally caught
> an avoidable warning which is possitive.

The GDALOpen() function provides no mechanism to ensure a particular driver
is used to open a file, so we often get the situation you see with jpeg2000
files where there are several drivers for the same format.

>>>   2) how can I resolve the warning
>> I'm not sure if this is a serious warning.  You might want to try
>> generating your file with the extra option -co PROFILE=BASELINE_1 and
>> see if that helps.  I suspect that is similar to the Sprofile=1 Kakadu
>> option.  If the problem persists you might want to take it up on the
>> ECW SDK forums at ermapper.com.
> 
> It helped.  Everywhere I see references to read the ECW SDK... but the docs
> of the SDK do not explain the options (at least: I cannot find it)

My copy of the ECW SDK source code includes an SDK.pdf file.  Circa page
113 is a section on the CNCSFile::SetParameter() call defining the meaning
of various parameters affecting JPEG2000 creation.

I will conceed that referring to the SDK docs for these options is a bit
of a cop-out on my part. :-)

Best regards,

-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | President OSGF, http://osgeo.org