libmtp was invented by:

Richard Low <richard@wentnet.com>
Linus Walleij <triad@df.lth.se>

We both came to do libmtp after working on the libnjb
project, which was all about Creative Technology devices
implementing the OASiS and PDE protocols.

libmtp is however largely based on libptp2, which was created by
Mariusz Woloszyn <emsi@ipartners.pl> as part of gPhoto2 then
derived into its own project.

We later started to use libgphoto2 which is also based on the same
code as libptp2 but with large contributions from
Marcus Meissner <marcus@jet.franken.de>. Marcus is also a 
contributor on libmtp from time to time and we're great friends.

Other contributors to libmtp include:

Andy Kelk <andy@mopoke.co.uk>
Chris A. Debenham <chris@adebenham.com>
Daniel Williams <danielw@iinet.net.au>
Dave Kelly <libmtp@ravelox.co.uk>
Matthew Wilcox <matthew@wil.cx>
Robert Reardon <rreardon@monkshatch.vispa.com>
Orson Teodoro <orsonteodoro@yahoo.com>
Ted Bullock <tbullock@canada.com>
Sean Kellogg <skellogg@gmail.com>
Tero Saarni <tero.saarni@gmail.com>
Jeff Mitchell <kde-dev@emailgoeshere.com>
Johannes Huber <johub1180@gmx.at>
Alistair Boyle <alistair.js.boyle@gmail.com>
Chris Bagwell <chris@cnpbagwell.com>
Joseph Nahmias <joe@nahmias.net>
Florent Mertens <flomertens@gmail.com>
Alvin <alvinbeach@gmail.com>