[Proj] ESRI proj codes
mkennedy2 at earthlink.net
Thu Sep 8 23:30:28 EST 2011
>Date: Thu, 8 Sep 2011 08:16:18 -0700
>From: Eric Miller <EMiller at dfg.ca.gov>
>Subject: Re: [Proj] ESRI proj codes
>To: <proj at lists.maptools.org>
>ESRI documents the various codes in their online help. I'm not sure if there is a single place for all of them (outside the SDK header file pedef.h which is considered a "trade secret"). For instance, the C++ API has several projection related constants.
>And geographic coordinate systems ...
>Eric G. Miller
>CA Dept. of Fish & Game
>>>> On 9/8/2011 at 6:32 AM, Irwin Scollar <al001 at uni-koeln.de> wrote:
>> The NAD directory of proj4 contains the files esri and esri-other
>> with additional codes numbered above 100000.
>> These useful additional codes are not recognized by the EPSG web site
>> http://www.epsg-registry.org/. They are also not in the official
>> Access database file EPSG_v7_9.mdb. They are however linked on the
>> http://spatialreference.org/ref/epsg/ site.
>> Is there an Internet source for the latest ESRI data which can be
>> used to create a supplementary table for the EPSG Access database and
>> which can be updated when ESRI or EPSG adds or changes something?
>> Irwin Scollar
There currently is not a complete list available online. The ArcObjects enumeration lists are not complete. These are definitions defined by Esri. Sometimes EPSG adds the definitions later, and then Esri updates the well-known IDs to the EPSG one (as more authoritative). Some are beyond the scope of EPSG, like the county-level or multi-county-level systems in use in some US states.
The pedef.h file is not considered a trade secret! It used to be included in the online help for ArcSDE, but I believe we stopped that when the files got pretty large. It's not really enough information to build the PROJ tables. You would need access to the well-known text strings, or the PE library to get the parameters, unit, gcs, etc.
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