[Proj] grid tool

[Paul Kelly]

On Sat, 18 Nov 2006, cp wrote:

> Does it exists a tool that makes a conversion from a binary NTv1, NTv2 or
> CTABLE format to an ascii format ?

I have used GDAit for this (NTv2 <--> ASCII) successfully several times:
http://www.sli.unimelb.edu.au/gda94/

> If not, does it exists some documentation about these formats ?

See appendices to the GDAit Users Manual at the above site, also some of 
my notes on getting it working with PROJ.4 here:
http://www.stjohnspoint.co.uk/gis/france.htm

Good luck,

Paul