delta mfcc and mfc file format (sphinx 3)

[abhishek]

Hi Nickolay,

Can you please help me with these two questions I have? I want to create my own features which make use of MFCCs (static, delta and delta-delta).

1> I want to know how does sphinx calculate delta and delta-delta features on the frame boundaries (frame 1,2,3 and frame N-2,N-1,N). I want to construct full MFCC vector which will have all three vectors i.e. static , delta , delta-delta.
Basically my question is , given a static mfcc vetor, how to find the corresponding delta and delta-delta vector to construct a complete 39x1 feature vector?

I want to use 39x1 vector obtained above to construct new feature vector.

2> My second question is, how to write this new feature vector stream in to the feature files in sphinx format. Can I get the sphinx feature file format somewhere for generic features?
Then, I want to stop dynamic computation of delta and delta-delta features. How can I do it in sphinx3?

Thank you very much in advance,
Abhishek.

[Nickolay V. Shmyrev]

See another post https://sourceforge.net/forum/message.php?msg_id=4817339

[Jan]

Hi,
I'd be also very interested to get the answers to these questions.
But it seems the page under this link does not exist ((

thanks...

[Nickolay V. Shmyrev]

how to find the corresponding delta and delta-delta vector to construct a complete 39x1 feature vector?

Read the code

Can I get the sphinx feature file format somewhere for generic features?

http://cmusphinx.sourceforge.net/wiki/mfcformat

Then, I want to stop dynamic computation of delta and delta-delta features. How can I do it in sphinx3?

Configure frontend with -feat 1s_c