Recognizing spoken words

Now that we have learnt all the techniques to analyze speech signals, let's go ahead and see how to recognize spoken words. Speech recognition systems take audio signals as input and recognize the words being spoken. We will use Hidden Markov Models (HMMs) for this task.

As we discussed in the previous chapter, HMMs are great at analyzing sequential data. An audio signal is a time series signal, which is a manifestation of sequential data. The assumption is that the outputs are being generated by the system going through a series of hidden states. Our goal is to find out what these hidden states are so that we can identify the words in our signal. If you are interesting in digging deeper, you can check out this link: https://www.robots.ox.ac.uk/~vgg/rg/slides/hmm.pdf .

We will be using a package called hmmlearn to build our speech recognition system. You can learn more about it here: http://hmmlearn.readthedocs.org/en/latest . You can install the package by...