I'm looking for an introductory paper/book on HMM (best for newbies, other than Wikipedia, please) to start working with. I'm interested in gesture recognition particularly. Any hints are really appreciated. Thank you in advance.
The first poster has identified the paper that is the best starting point in my opinion. Understand this paper and you can apply it to any problem. Other references that are useful concern Markov chain models in general. The books by (1) R. A. Howard; (2) Isaacson & Madsen; (3) Kemeny & Snell, come to mind.
There is an example of the implementation of a nonhomogeneous hidden Markov model in the paper in the link. This is for a so-called fractal model where the trasnsition probability has a known functional form for time variation.
A non-homogeneous HMM is also used in a paper I recently wrote on passive sonar tracking (see second link). This is used to model a uniformly accelerating acoustic source. The implementation was in Matlab but I cannot provide the code. It does involve creating transition matrices for each separate time instant and therefore uses more storage than a standard HMM.
Article Evaluation and Estimation of Various Markov Models with Appl...
Conference Paper A High Performance 1-D Hidden Markov Model Tracker for Passi...
Rabiner's IEEE tutorial on HMMs is the best. There is also a Signal Processing magazine article that is pretty good. If you want references for the state estimation problem in HMMs, try the paper below. This assumes you already can identify the HMM parameters, which may not be the case for your area.
Conference Paper A High Performance 1-D Hidden Markov Model Tracker for Passi...