[Gdal-dev] internals of ecw file

[Frank Warmerdam]

nicholas.g.lawrence at mainroads.qld.gov.au wrote:
> I am trying to write a mapbasic program that, amongst
> other things, interrogates an ecw file for information
> such as;
> - datum/projection
> - bounding coordinates?
> My plan is to open the binary file, and use
> a Get statement to extract information. But I
> don't know where in the ecw to look.
> 
> Does anyone know about the internals of an
> ecw file?

Nick,

I have always used the ECW SDK to access ecw files, and haven't
looked into the internal organization.  You could review the
ECW SDK source code to work out rough layout of the header of
the ECW file, or perhaps examine it in a binary editor to find
particular items.  That is if you are convinced you want to
directly open the file and read it yourself.

Alternatively, you could use the ECW SDK or GDAL to get this
information.

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Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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