[Kaldi-users] matrix archive format

[Simon K. <sim...@gm...>]

Hi,

A colleague of mine experimented with some 'exotic' feature vectors 
using Matlab, and now we would like to see how the pretty great Kaldi 
tools might be used to train some model using them.

I believe, the clean way to do it, would be to write a routine that 
creates these features using the Kaldi libraries, and then writing them 
to an archive. However, I fear this will involve quite some work, and as 
we do not know if it will be an endeavor worth the effort, we would like 
to start off to export the features in a Kaldi readable format from 
Matlab. This so far seemed the smaller effort.

I tried to find out about the way those files are structured, but got 
lost somewhere on the way.

Looking into compute-mfcc-feats.cc, I saw that there is:

BaseFloatMatrixWriter kaldi_writer;

which is later used to write the archive:

kaldi_writer.Write(utt, features);

Trying to find what this call actually does, I got lost.

I found this:

http://kaldi.sourceforge.net/group__table__types.html#gaa9b0c000a2d8bbf1a7df386024110883

and from there this:

http://kaldi.sourceforge.net/table-types_8h_source.html#l00036

and then eventually this:

http://kaldi.sourceforge.net/classkaldi_1_1TableWriter.html


I however could not yet find anything I could use to understand the 
particular format of the archive file of feature vectors.

The scp file should be straightforward, but I hope someone of you could 
point me to the right resource to learn how to write the matrices of a 
set of features in the correct archive format.

Perhaps doing a detour through non-binary files might be a way to get 
there, but this surely would be very unfavorable.

Thanks a lot,

Simon