initialize HiddenMarkovModelTrainer object

Question

i'm doing gesture recognition in python and one the the more complete library i've found that can manage Hidden Markov Model is nltk. But there is something that i can't understand.

First of all, the data. I have coordinates of the gesture and i have clustized them in 8 cluster (with k-means). so this is my gesture structure:

raw coordinates x,y: [[123,16], [120,16], [115,16], [111,16], [107,16], [103,17], ...]

centroids x,y : [[ 132.375        56.625     ]
                 [ 122.45454545   30.09090909]
                 [  70.5          27.33333333]
                 ...]

labels: [5 6 6 6 6 6 6 2 2 2 2 2 2 4 4 4 ...]

Now i want to train an HMM with Baum-Welch with my . So HiddenMarkovModelTrainer is my class.

I've found in internet some few more implementations of baum welch, but only in Matlab. the implementation of this algorithms tipically need this input:

baum-welch(X, alphabet, H)

where - X is the data for train (in my case - labels) - alphabet the possible values of the data (in my case - 0,1,2,3,4,5,6,7) - H the number of hidden states

Now i am confused because in ntlk.HiddenMarkovModelTrainer constructor i have to give states and symbols and i don't know what they should be, considering that the data to train X is the imput of HiddenMarkovModelTrainer.train_unsupervised() method i think that my alphabet is symbol.. i don't know what to put in states.

i hope my explanation is clear even if my english is poor.