Hello, currently I am trying to get involved into the dictionary acquisition project.  At the moment, I have a question concerning the IPA transcription of the German word "Europa".  The IPA transcription is displayed as "??????o?pa".  But in the PhoneSet, there is the example "Kreuz [???]". Which transcription should I use?

Hi Ralf,

actually, both are fine. The Wiktionary-Guideline uses ???, so we should probably stick with that. The phoneset definition used ???, mostly because the cited SAMPA-versions used OY.

Anyways, phonetically speaking there is a difference (??? ends in a rounded manner, while ??? does no), but phonemically (the level we are using here, because we can't model all the different variants anyway) they are identical for German. 

There will pe quite an amount of (partly) automatic checking and streamlining, to get the dictionary in a usable shape. Identifying and unifying ??? and ??? won't be a problem, so don't worry about them too much.

Cheers! Timo

In other news: just checked your submissions (thank you!) and have some comments about the first "r" in "festeren, festerer": I've changed those to fEst@r@n and fEst@r6, as the r-sound is actually realized (only use /6/ when the "r" is not audible). I also added this example to the Wiktionary-page because this was not clear on their page.

I also changed ve:nIg to ve:nIC, due to Auslautverhärtung. (southern germans may actually say ve:nIg, but that's dialect :-)

Please excuse my using SAMPA instead of IPA in this post. It's just so much easier to type.

Hello Timo,

1. OK, I won't worry about the difference between ??? and ?? too much.

2. I will keep that in mind that I have to transcribe fEst@r6 (correct) instead of fEst66 (wrong).

3.  Now I have learned something.  I didn't know that ve:nIg is dialect.

Greetings, Ralf

At the moment, I am preparing the entry for "Donnerstag".  I would like to say something about the "R".  In my opinion, the correct IPA transcription should be "d?n??sta?k".  But I decided to choose the transcription like indicated in the wiktionary.  And I think that you should allow the "?" (examples: dort [d??t], wird [v??t]).  I would like to make it right from the beginning.

I believe the wiktionary is right. The case is different from the cases you mention (dort and wird) in two regards. First, the /s/ in Donnerstag is a linking-s (Fugen-s) which is preceded by a morpheme boundary (unlike the [t]s in dort and wird) and thus the attachment between /??/ is stronger than between /?s/. Now, why am I writing /??/? Because with "//" we're on the phonemic level while with "[]" we're on the phonetic level. The phonemes /??/ are reduced to [?] by so-called postphonological processes. This reduction is the other thing which makes Donnerstag different from dort, as it does not occur in the latter.

Now it will become difficult: I argue against different Rs, as the realization of (phonologic) /r/ in German varies widely both between individuals as well as dialectally. It's a mess. Thus, I would actually just use [r] as our generic R and keep the uppercase symbol if we ever want to transcribe English Rs (which also vary widely between dialects). As before, don't worry about this too much yet, but I'll likely add some post-processing to change all r-variants to [r].

Hello Timo,

What do you think about the following idea?  We could build two German pronunciation lexicons.

Lexicon #1: IPA (with different Rs), PLS, GPL.

Lexicon #2: Your PhoneSet (our generic R), designed for the use with HTK, or Sphinx; GPL.

You have the necessary programming skills.  And it wouldn't be bad, if there would be a free IPA-lexicon.

I just took a look into the Wikipedia to learn more about the difference between phone and phoneme.  Well, I understand the concept.  But what is the impact of this distinction when it comes to speech recognition?  I don't know.

Greetings, Ralf

At the moment, I am thinking about the IPA transcription of the word "verlassen".  The dictionary acquisition project proposes the following transcription: "f????lasn?".  But in my opinion, this is in conflict with the Wiktionary transcription guideline.  The transcription should be either "f????lasn?", or "f???lasn?". I am trying to understand the concept.  Or did I misunderstand something?

Addition: The same problem applies to the words  "daher", and "verlassen."

Hm... "ver-" is a prefix, so it should be unstressed. Thus "er" becomes [?]: [f?lasn?]. Then again, the "er" is slightly prolonged compared to e.g. "verraten". If it's prolonged, then it should in fact be transcribed as [f????lasn?], which I think we should use. 

The funny thing is, that systematically (at least as far as it is explained in the guidelines) you are right: Phonemically, the vowel in the prefix "ver-" is Schwa followed by an /r/ (whichever, you know my opinion :o) So, [f???lasn?] would be good. But, that's not what it sounds like (kinda difficult to explain the difference in a written-only forum, but listen to yourself, you'll hear it): There is definitely no [r] in verlassen (notice the brackets, I'm talking about the phonetic layer, not about the phonemic layer). So, if there's no [r], then it must be gone (we said it was there phonemically, didn't we?) due to contraction, and [f????lasn?] must be right, right? Not quite. If there has been a contraction, the Schwa must be gone now and we arrive at my first proposal. 

Now the rescue: If "ver-" is not unstressed (at least not completely unstressed, but a little longer than usual), than the Schwa doesn't have to stay a Schwa. Instead it becomes some other kind of "e". If we listen carefully, we notice, it's actually an [?], that it's becoming and that the following /r/ is becoming [?]!

It's slightly different for "daher": it usually sounds different than "da, Herr", thus we should transcribe it as [da:he:?]. 

Just as a side notice: Phonetic transcription is very hard work, especially if you're not (yet) a studied linguist/phonetician and I think you're doing really really well at it. Keep up the good work!

Hi Ralf,

that sounds good to me. I hope to be able to look into the lexicon a bit this weekend and can then automatically generate both PLS as well as the plain-text stuff I need for Sphinx. Your work till then (and beyond) is greatly appreciated!

The distinction between phonetics and phonology in ASR is always a bit weird: In general we want to and can only recognize phones (that is, the actual realizations of abstract phonemes). Phones are supposed to describe precisely the differences between all human speech sounds. They tell us exactly, what has been uttered and how. On the other hand, phonemes have the nice property of being abstract thus (in theory) working cross-realization, cross-person, cross-dialect, etc. Obviously this is doomed to fail: As current ASR doesn't have proper phonologic modules that describe how the cross-* phonemes should be mapped on realization-specific phones, having a pure phonologic lexicon doesn't help. A pure phonetic lexicon doesn't help either, because every realization is unique. So, we are stuck somewhere in between, where we try to model phonetic differences between realizations that are relevant to ASR.

One example: [x] as in "Nacht" and [ç] as in "nicht" are definitely two different sounds (and thus different phones), but they are both the same phoneme in German (/x/ or /ç/ either way you like), because the realization as [x] or [ç] can be contextually determined from the preceding vowel: [x] after /a/, /u/, /o/ and /au/, [ç] otherwise. *But*: For ASR, their is a huge difference between [x] and [ç]. Relying on triphones (senones in Sphinx-lingo) for the different contextual realizations of [x]/[ç] would be possible. But it would be very inefficient, because state-tying and even more context-independent modelling assumes, that segments always sound more-or-less alike. Thus, coding [x]/[ç] explicitly greatly improves performance.

A counter example: /r/ is realized in many different ways, depending mostly on dialect, speaker, etc. This is impossible to model in a dictionary. But, as there are so many possible realizations, it doesn't help to split the /r/ into slightly different context-dependent realizations, as the superimposed inter-personal differences are much larger. It would actually harm in training (and decoding), because the training material (respectively the probabilities for decoding) would be split between the different models, resulting in worse recognition. Nonetheless, for an instructive dictionary, distinguishing both /r/'s would be fine.

Hope this helps a little and take it with a grain of salt,
Timo