[hts-users:03073] Re: the order of CMLLR transforms being applied to models in the course of HTS engine generation

[Hui LIANG <tshlmail-hts@xxxxxxxxx>]

Thanks a lot, 全さん. I tried the option -H, and found that -H and one more AX command resulted in the same HTS engine.

"HAdapt:ApplyCompXForm() first applies set_A then set_B."

This is exactly my concern. According to my understanding of the estimation/training of a cascade of CMLLR transforms, parent transforms (set_A) are applied to features and thus set_B should bridge the gap between speaker-independent models and adapted features. As a result, in the course of HTS engine generation, I feel that it is set_B that should be applied to the speaker-independent models first. In other words, set_B (or set_A) is "closer" to the model (or feature) side during training. set_B should be still "closer" to the model side during HTS engine generation.

Does swapping the two sets of CMLLR transforms make no/negligible difference? Or, my understanding is wrong?

Thanks,
Hui



----- Original Message -----
From: Heiga ZEN (Byung Ha CHUN) <heigazen@xxxxxxxxxx>
To: Hui LIANG <tshlmail-hts@xxxxxxxxx>
Cc: "hts-users@xxxxxxxxxxxxxxx" <hts-users@xxxxxxxxxxxxxxx>
Sent: Wednesday, 19 October 2011, 15:57
Subject: [hts-users:03072] Re: the order of CMLLR transforms being applied to models in the course of HTS engine generation

Hi,

2011/10/19 Hui LIANG <tshlmail-hts@xxxxxxxxx>:

> Suppose I have two sets of CMLLR transforms, set_A and set_B. set_A is parent transforms, meaning the following line
>
> <PARENTXFORM>~a "set_A"
>
> can be found in set_B.
>
> In the training phase, set_A is given and applied to features for the estimation of set_B (which bridges the gap between speaker-independent models and set_A-adapted features). But I am not sure whether HHEd firstly applies set_A or set_B to the speaker-independent models when I generate an HTS engine with the following commands:
>
> AX "set_A"
> AX "set_B"
> LT "(a decision tree)"
> CT "(output tree)"
> CM "(output engine file)"

I think

AX "set_B"
LT "(a decision tree)"
CT "(output tree)"
CM "(output engine file)"

is enough, as set_B has <PARENTXFORM>~a "set_A". HAdapt:ApplyCompXForm() first applies set_A then set_B. You may need to load set_A by -H option, though.

Regards,

Heiga

-- 
Heiga ZEN (in Japanese)
Byung Ha CHUN (in Korean)
<heigazen@xxxxxxxxxx>