At the moment, it seems that the HTK website is not reachable. Here is what you can do:
- install simon,
- read the simon handbook,
- wait until the HTK website is available. Probably, it is just a temporary issue. No need to worry.
You can install simon without installing HTK. But to build speech models, you need HTK.
Something for mathematicians who want to learn more about the theoretical background of HMMs in general: read the PDF The Application of Hidden Markov Models in Speech Recognition.
Why should you read the PDF with the theoretical background? Personally, I would understand just about 1% of the things they explain (I read parts of the HTK book – I understood almost nothing). But at least I understand one fundamental thing: HMMs are a great thing for speech recognition. The HTK toolkit handles HMMs. And simon makes use of the HTK toolkit (the HTK toolkit has to be installed separately; it is not part of simon).
In the end, it is working. Watch my newest video where I am dictating 200 German words with simon.
So there are several things that you can do until the HTK toolkit is available again.