[OSGeo-Standards] Please review: Open Letter asking to avoid format fragmentation in LiDAR standards

[Sebastiaan Couwenberg]

Hi Martin,

On 04/13/2015 06:28 AM, Martin Isenburg wrote:
> This is the very first time (since LASzip's LGPL release in late 2010) that
> someone brings a possible issue with a license incompatibility between LGPL
> and FastAC to our attention. You can rest assured that this was absolutely
> *NOT* ESRI's reason for creating the closed "LAZ clone" ...

This is not the first time, the first time I contacted you about it was
on 2014-12-25. Look for Message-ID <549C7BBB.8010900 at xs4all.nl> in your
@rapidlasso.com mailbox or a thread with the subject "LASzip FastAC code
license issue".

For the record, I first contacted the FastAC authors about this on
2014-08-21. This discussion did not result in FastAC relicensing, only a
statement of intent.

I contacted the FastAC authors again on 2014-12-25 and included the
libLAS/LASzip maintainers (Howard Butler & Martin Isenburg) in the
recipients. Howard responded and offered his help, no word from Martin
or the FastAC authors (not unexpected due to holiday season).

If the FastAC issue is not (part) of the reasons for ESRI I wonder what
the "legal issues" and "code problems" were that ESRI addressed with
Optimized LAS, the FastAC issue still seems a very good explanation for
this.

> In fact, I would not be surprised in the least if the ESRI implementation
> is also based on that very same FastAC code,  given the nearly identical
> performance of LAZ and zLAS and the lack of other similar efficient
> artithmetic coding implementations ...

I surely hope the ESRI legal and engineering departments are better than
that.

My naive assumption is that they just used zlib or one of its modern
variants (xz).

Has anyone tried to decompile or reverse engineer Optimized LAS?

Kind Regards,

Bas

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