Re: tamil character set choice for a font encoding scheme

[Vasu Renganathan <vasur@ccat.sas.upenn.edu>]

Dear Kalyan and Sujatha,

I like to point out a few problems, at least from the point of view of
Tamil linguistics researchers, in the following transliteration chart
Kalyan has suggested. 

> 
> CHARACTER CHOICES
> vowels: 12   
>        (a, aa/A, i, ii/I, u, oo/U, e, ee/E, ai, o, O, au, ak)

Use of oo for U may not be appropriate because it is followed based on
English sound system.  I don't understand why Tamil transliteration scheme
should follow English sound system.  For example, English words with oo
are pronounced U as in cool, tool and so on.  Why should we use oo for U? 
Some other existing transliteration schemes also wrongly use ee for I
based on English words like: reel, wheel etc. 

I think Tamil lexicon has a standardized transliteration scheme that is
accepted by many researchers, and it can be adopted for our purpose as
well with suitable modifications.   

> consonants:  18 
>       (ka, nga, ca, nya, da/ta, Na, tha, n^a, pa, ma, ya, 
>      ra, la,  va, zha, Ra, La, na )

1) You are using ^ for dental na.  Why do we need a non-alphabetic
character in the transliteration scheme?  We use combinations like nga,
nya and so on to represent other characters.  Tamil University is using nd
for dental n, which makes sense, in the sense that both are dental
consonants. n is dental and d (dh) is dental too (spread the tip of tounge
on the front teeth), and thus we make a combination of dental consonants
to represent dental n. So, nda may be used instead of n^a following the
scheme adopted by Tamil University. 

2) You seem to mix voiced consonant in the chart da/ta. Again, based on
the scheme that Tamil lexicon adopts, Ta may be used for (eTTu, paTTu
etc.,), and t may be used for (pattu 'ten', vaattu 'duck' and so on.) 
Use of da/ta here reflects English sound system, like in the words time,
tree etc. 

Like Sujatha points out, we always have problem with three n's, l's and
r's, when we attempt to transliterate them. (nd,n,N / l, L/ r, R).  Where
does zh belong to?  It is considered an r(hotic) sound rather than an
l(ateral) sound.

The transliteration scheme adopted by Tamil Lexicon conforms to the
standards of IPA (International Phonetic Alphabet) system, and I don't
think there could be any problem in adopting it for the purposes of
computer processing.  I think the use of English sound system for Tamil
transliteration scheme should be avoided. 

With kind regards,
Vasu.