Electronics and Information Technology
Exposition - ELITEX 2005
India Habitat Centre, Lodhi Road,
New Delhi.
25 - 26 April 2005
Nurturing Living Languages
Mahesh D. Kulkarni
C-DAC GIST Group
mdk@cdac.in
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Nurturing Living Languages
Multimodal System
(Human Computer Interface)
for Indian languages
Issues - Solutions
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Multimodal System
•
Enables users to communicate with computers via several modes such
as Keyboard, OCR, Speech, Gesture, Gaze, Visual, etc.
•
Major challenge for computer system designers lies in simplifying the
Human Machine Interface.
•
Researchers all over the world are inventing different modes of
interactions, some of them with little or no success.
•
No single mode is sufficient for effective communication with the
machine.
•
Some of the popular interaction mechanisms are
• Keyboard
• Unistroke
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Graffiti
Predictive writing
OCR
Speech (limited vocabulary)
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Nurturing Living Languages
Multimodal System for Indian languages
•
•
•
•
•
•
•
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Challenges
Multilingual – 22 scheduled languages.
Complex script(s) as compared to English.
(especially poses problems for OCR)
While inputting, many to one and many to many relationship unlike
English.
Limited availability of linguistic resources.
Layman terminology versus pure linguistics terminology.
Various dialects poses challenge for speech input
Impact
Lack of efficient Indian language based multimodal system has put
restriction on content creation.
Possible solution
Need for Development of Expert /Smart writing systems backed up with
Multimodal inputs, Linguistic Resources such as Spellcheckers, Grammar
checker,Synonyms, Antonyms, Thesauri, Domain based Dictionaries,
Phrases and references.
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English Language
English base Character - 26
A B C D
………
Hindi Language
Base character - 80
vowel character – 12
Half character – 43
Matra character - 12
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• Because of unavailability of
Indian language keyboard layout(s).
processing power, mechanical
Typewriter were devised, which
were based on the fact “the way
you see the way you write”
• INSCRIPT - Popular and widely
used & has become de-facto
standard.
• Based on phonetic structure of
Indian languages – “the way
speak the way you write.
• And Phonetic English for Urban
users
Limitations in mobile world
• Its very bulky, difficult to carry & large as compared to the target
device itself
• Use of both hands, not suitable for portable, mobile devices
• Not possible to use without training
• More than 80 keys required with UNSHIFT / SHIFT operations
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Virtual / LASER keyboard
• PDA’s, Cellular telephones.
• Tablet PCs, Laptops.
• Industrial, sterile & medical
environments.
• Test Equipment.
• Transport (Air, Rail,
Automotive).
Limitations
• Need a proper surface to
display Image.
• Typing is cumbersome, since
the finger positions and
movements are restricted.
• Speed limitations.
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• KITTY, a finger-mounted
keyboard for data entry into
PDA's, Pocket PC's and
Wearable Computers has
been developed at the
University of California in
Irvine.
KITTY – Keyboard Independent Touch
Typing
© University of California and Senseboard respectively.
• Two hand-mounted
devices connect to the
target computing device
with the help of Blue tooth
wireless networking
technology.
• The user can type on a
hard surface like a desk or
table, or into the air.
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• Each character is
represented by a
single stroke & hence
no segmentation
problem
Unistroke Inputting
• The system does not
need to use up
resources to figure out
where one character
ends and another
begins
• No need to write characters within bounding boxes, characters can
be recognized even when they are written one on top of the other.
• Even can be used by blind person.
Limitations
• However require the user to spend some time learning the characters.
• Complex implementation for Asian languages.
• More oriented towards English.
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Graffiti inputting
• Requires minimal time
for learning the alphabet.
• This is all because Graffiti
is easy to learn while
Unistrokes is
comparatively harder.
• Though Unistrokes is a
faster mode for inputting
text than Graffiti, nobody
uses Unistrokes
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Nurturing Living Languages
Non-Predictive & Predictive
Inputting mechanism for
Handheld / Mobile Devices
By
C-DAC GIST Group
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Multitap text entry mechanism
English
Hindi / Indian languages
English has 26 alphabets
only.
In Hindi there are around 80 basic
characters, 43 half characters, 12 vowels,
12 matras making it more than 147
characters.
These are spread over 9
keys. I.e. 3 to 4
characters on single key.
Spreading these 80 characters & half,
vowels & matras over the 10 keys, it comes
to around 9 to 10 characters on one key.
To get the desired
character user needs to
press the key up to 4
times.
It will be very cumbersome when inputting
in a multi-tap way.
Since more key presses
are required to get the
required characters it
becomes more tedious to
type a bigger matter
Inputting the bigger message using this
kind of mechanism for Indian languages is
next to impossible.
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Comparative study of English & Hindi
English
• Single character
combinations
26
• Two character
combinations
52
• Three character
combinations.
4056
Hindi
• Single character
combinations
80
• Two characters
combinations
6889
• Three characters 571787
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Multitap
• 12 keys are required to input the
character
• If a character is missed out then
you need to restart all over again
• Ideally suitable for less than 3-4
character per key.
• Not suitable for Indian language
inputting, since almost 7-8
characters are required to be
placed on each key.
(Basic character 80, half character 43, vowels
12, Matra 12)
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Two key non-predictive
• 4 keys are required to input the
character
• Any character entered in just two
key press.
• Key mapping done on basis of
vargas & hence easy to remember.
• Very short learning time. (3-5
minutes)
• No need to remember the keys
• Guiding reduces mistakes
• With the same keyboard layout all
Indian languages can be inputted,
so no need to learn again for other
language.
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Two key non-predictive
• 13 keys are required to input the
character
• * Key is the mode key used for
selecting halant / half character.
Technology given to MNC’s
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Predictive writing
• This should address the need of fast inputting using limited keys.
• Should not take more than one key press per characters.
• Should help in auto completion of word, so less key press than length
of the word.
• Fast searching with help of most commonly used words dictionary as
a backup.
• Can manage the user-defined words also.
• C-DAC GIST has developed predictive writing for Hindi language and
work in progress for others.
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• Because of nature of script, more
complex to implement than any
other language.
• “Accuracy increase” is a function
of continuous development
process.
• Stepwise approach to achieve
good level of prediction.
• Approaches for Predictive
inputting for devices
•
•
•
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Pure Dictionary based.
Dictionary plus rule based
approach
Addition of Domain specific
dictionaries.
Increase in accuracy by
analyzing live data &
accordingly enhancing built-in
dictionaries.
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Predictive writing Demo
5 keys required to complete
the word Dhanyavad
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Features :
• Highly efficient algorithm & automatic prediction of the frequently
used words by the user.
• Auto tracking of the frequently used words by the user & giving them
priority.
• Currently 25,000 common “spoken Hindi” words.
• Addition of words by the user which are not available in the
dictionary with the help of non-predictive mechanism.
• Current memory requirements
•
180 KB for 25,000 words - uncompressed
•
8 KB for code
•
3 KB scratch memory.
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Conclusions
• Urgent need for Development of Expert /Smart writing systems
backed up with Multimodal inputs, Linguistic Resources such as
Spellcheckers, Grammar Checker,Synonyms, Antonyms, Thesauri,
Domain based Dictionaries, Phrases and References.
• Standardization for inputting Indian languages through limited keys.
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THANK YOU
Nurturing living languages
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