Hindi to Urdu Conversion: Beyond Simple Transliteration

Proceedings of the Conference on Language & Technology 2009

Bushra Jawaid, Tafseer Ahmed University Of Malta, Malta, Universitaet Konstanz, Germany [email protected], [email protected]

Abstract text comfortably or we need to deal the issues which are beyond transliteration. This paper incorporates a detailed analysis of existing work on Hindi to Urdu transliteration systems 2. Hindi-Urdu transliteration: a brief and finds the enhancements they required. It lists the review issues that are beyond the scope of character by character mapping. The issues include multiple same It has already mentioned that both languages use sound Urdu characters against one Hindi character. different scripts for writing. Here we discuss these Moreover, it deals with the issues when the same word scripts briefly. or words are written in two different ways. The paper Hindi is written in devnagri script and it is read and lists the differences in pronunciation, spelling and written from left to right. All consonants in Hindi writing style. It presents solution to these issues that inherit [ ] sound. All the vowels in Hindi are attached goes beyond transliteration. to the top or bottom of the consonant or to an [ ] 1. Introduction vowel sign attached to the right of the consonant, with the exception of the [ ] vowel sign, which is attached Urdu and Hindi are considered as different styles of on the left [5]. Hindi has 29 non-aspirated, and 15 the same language. These languages share grammar aspirated consonants , and 11 vowels ( svara ) [2]. A and differ in vocabulary and writing script. Urdu uses syllable ( akshara ) is formed by the combination of zero more Arabic and Persian words and is written in or one consonants and one vowel. [5] Nastaleeq script. Nevertheless, Hindi uses more Nastalique script is read and written from right-to- Sanskrit words and is written in Devnagri script. left. Nastalique, a cursive, context-sensitive and a In conversation, Urdu and Hindi are intelligible. highly complex writing system, is widely used for the Television programs and cinema films are watched in Urdu orthography. The shape assumed by a character the both languages communities without the need of in a word is context sensitive. The Urdu alphabet translation. A Pakistani Urdu speaker understands the contains 35 simple consonants, 15 aspirated Indian Hindi films, and an Indian Hindi speaker consonants, one character for nasal sound, 15 understands Urdu programs. The problem arises when diacritical marks, 10 digits and other symbols. [2] a person tries to read written text of the other language. Below is the consonant chart for Hindi and its Most of the people cannot read script of the other respective Urdu character. language. A considerable amount of work is done on Hindi to Table 1: Mapping of Hindi and Urdu Urdu transliteration. CRULP [1] and Malik [2] has consonants discussed and implemented issues of Hindi to Urdu transliteration. There are two fundamental goals of this paper. The first goal is to find problems / short Devnagri Consonants Urdu Consonants comings in the models / implementations of [1] and [2], and to propose solutions of these problems. The Letter Name Letter Name second goal is to find whether any accurate character by character Hindi to Urdu transliteration will be KA Kaaf enough for the Urdu reader to read transliterated Hindi

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KHA Kaaf-Hay BA Ď Bay

GA Gaaf BHA Bay-Hay

GHA Gaaf-Hay MA Meem

NGA Noon YA č Bari-Yeh

CA Chay RA ŋ Ray

CHA Chay-Hay LA ! Laam

JA Jeem VA ő Wow

JHA Jeem-Hay SHA # Sheen

NYA ĕ SSA # Sheen

TTA Ttay $ % Seen/ Saay/ SA & Suad TTHA Ttay-Hay HA ' Ī ) Hay DDA Ddaal Below is the Vowel chart for Hindi and Urdu. DDHA Ī Ddaal-Hay Table 2: Mapping of Hindi and Urdu vowels

NNA Č Hindi Vowels Urdu Vowels TA Tay/ Toay Ő Diacritical Letter Letter Vowel Mark THA Tay-Hay Č DA Ē Daal * ǡ DHA ĪĒ Daal-Hay ɪ ِ NA Noon ď i PA Pay ʊ ُ PHA Pay-Hay u

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differences in writing style and vocabulary. We are ر +ِ presenting list of all these issues in the following text. (consonant+ ṛ Most of the Hindi presented in the following discussion vowel) is taken from [3] and [4] and few example sentences are constructed. In section 4, we will present solutions čČ e for these issues. , č Č æ 3.1. Transliteration between different scripts

o After transliterating the Hindi text by exploiting the CRULP’s transliterator and later on comparing those results with the expected output of Malik’s system, we ɔ ő found following issues that remained unsolved in either one or both of the systems. In Table 2 we have listed all the Urdu vowel symbols or group of vowels against each Hindi vowel 3.1.1. Same/similar sound character. In the following to represent Hindi vowel sounds. Only exception is example sentence, the word “ 51Ņ7 ” is not transliterated vowel “ ” whose vowel sound maps on Urdu correctly. In problem-word “ t” sound character should be transliterated into “ ” instead of “ ”. consonant and vowel character sounds. Current Ő transliteration systems don’t provide support for the independent form of this vowel. CRULP’s output for (1) .” شِ “ the sample word rishi) is ( 0:51Ņ7 5 8.őĒ9

Here we are writing down few sample words by Similar sound character problem always occurs due reading those a reader can have an idea of difference in to multiple Urdu characters against one Hindi writing style of both languages. character, as can be seen in table 1. For the same / ŋČ-.ĕĒ reason, the wrong selection of character has often found for words that end on “ ”. 01Ňņ.

4ĕņ (2) 3. Issues in Hindi-Urdu conversion @ , / / 8:5ĕ?ĕń ČAĩĕ=>ņ: ĕ.ĕń< The paper discusses the issues in Hindi to Urdu conversion that are remained unsolved in CRULP’s In (2), for example, word “ ĕ=>ņ: ” is written with “ Č” and Malik’s system. To identify these problems we instead of “ )”. Table 4 gives the list of same sound made a small survey of Hindi text available at [3] and Urdu characters. [4]. We transliterated the Hindi text to Urdu using CRULP’s Hindi to Urdu transliterator. The problems Table 4: List of same sound Urdu characters identified in the converted text are listed. We explored Malik’s solution to find whether his algorithm and Sounds Urdu Default structures have solution of these problems. It was Characters list Characters for found that most of the problems are not solved by his for each sound Transliteration model too. Character The identified issues are of three types. The first type of issues has unsolved problems in character by t sound Ő đ character transliteration of Hindi text into Urdu script. s sound &đ $đ % $ But there are issues that are beyond the scope of character to character transliteration. There are z sound Dđ Eđ Fđ G D

26 Proceedings of the Conference on Language & Technology 2009

In Urdu when noon-ghunna comes in the middle of a sound Čđ Hđ I Č the word it is replaced by noon. Current transliteration systems map Hindi nasalized characters with noon- -at-end a sound Čđ Hđ Iđ ) Č ghunna of Urdu irrespective of its position in the word. The second issue is that few words in Urdu contain Systems that are built for Hindi to Urdu transliteration character “ ” but in pronunciation they produce currently have fixed transliteration rules defined for nasalized sound. same sound character mapping. Those rules map Hindi’s same sound characters on default Urdu characters as defined in Table 4. (5)?

Ĵ0:5?1 5YĕN Ĳ 5őŋ55 3.1.2. Characters similar in Shape. Transliteration 5YĕN Ĳ errors that occasionally occur are primarily due to the charcters that are exactly identical in shape in Devnagri Hindi speakers write these words the way they script and differs only by a dot addition. Errors are pronounce it. That’s why in the result of transliteration rarely found because of the missing dots and mostly we get “noon-ghunna” instead of “ ”, as in (5). due to the pronunciation differences between the speakers of the both languages. 3.1.4. Kasr-e-Izafat Issue. Kasr-e-Izafat is represented by (Zer) at the end of a word and is used to connect two words to form the compound word e.g. (3) [YČ->\ ŋĕ Words having izafat symbol produces [e] sound 5:5ĕ 5-?ŇAĩJ>ĲL 5ŋĕń effect during pronunciation. In devnagri script there is no concept of izafat to produce [e] sound that’s why Table 5: Chart of similar shape Hindi Indian native speakers use diacriticalmark [ ]whose characters independentformis []inplaceofthediacriticalmark Urdu Hindi Transliteration Errors [ ]whoseindependentformis[]forwrittingthese D đ , AĵĒ4D AĵĒ4N words. / O đ , 58P 58ń / (6) Ė đ !8Rĭ !őLń , T 0:J>ĳŋ8:ĺ ĕ1ŇĕT čŋĕ?>ĳ U đ UĕĳĒ ĕĳĒ , T T Thus,thiswrongdiacriticalmarkingasin(6)produces () instead of Izafat sign (Zer). Solution of the above 3.1.3. Nasalized sound character. In Urdu consonants is not present in either of the two systems. chart we have a single character to represent nasalized sound known as “noon-ghunna” ( ). 3.2. Different writing style

Hindi script has “chandrabindu” ( ) and “bindu” Even if a character by character mapping is modeled () diacritics to represent nasalized sound. There are successfully, there remain few differences in writing two problems in mapping of chandrabindu/bindu to conventions of Urdu and Hindi. These problems are Urdu script. The first problem arises when this beyond the scope of transliteration, and hence are not nasalized sound character occurs in the middle of the discussed in the two earlier works [1] and [2], but these word, as shown in (4): should be addressed because the Urdu reader expects to read the text having Urdu conventions.

(4) 3.2.1. Native words. There is a difference in writing 0:X>ĕW Č 9 conventions of native Indic words in Hindi and Urdu. TTTT TTTT Problem has been found in those words which end up

on vowel sound. Hindi language can have words that

27 Proceedings of the Conference on Language & Technology 2009 end on short vowel but Urdu language doesn’t contain words that end on short vowel. Same problem has been found in words borrowed The first issue arises for the words which end up on from English vocabulary. short vowel character. In Urdu writing system when a short vowel comes at the end of the word it is written (10) as a long vowel, as illustrated in example (7): / / //// , 8:5ceŅTT 5ńČJ>ĳ TT

(7) In example (10) “ / ” is the transliteration of eŅT English word “police”. This transliteration is correct according to its pronunciation but Urdu speakers write @ / 0:8ń ATT 4`aČŋ ŋ^ČX?>ĳĕ>ĲŋĕJ>ĳ5T ĲĒ5_.T “police” using long vowel: as “ e>Ĳ8 ”. Observe that the word “ AT 4` aČŋ ” has short vowel 3.2.3. Persio-Arabic words. Urdu’s vocabulary is ending. CRULP’s transliterator has not dealt with this comprised of many Persio-Arabic words. These issue whereas Malik [2] has presented his idea on a borrowings have their own writing conventions which particular problem but this problem is also present in Urdu speakers generally follow. his system. When Hindi speakers write persio-arabic words they Hindi and Urdu share a basic common vocabulary don’t follow the writting scheme of these borrowings. that includes pronouns and auxiliaries. Errors in Issues have been seen in the words that have silent- transliteration occur because of different writing Alif. Hindi speakers neglect silent-alif part in writing conventions which have been followed for words that because of the unawareness with the correct form of the are being used by both language speakers from same word. The lack in familiarity with the correct form of set of vocabulary. As shown in (8): a pronoun “ 9 ” is the words is depicted as in (11):

transliterated as “ 0 ”. (11) / , (8) 8:ĕbŋĕ 4ń0?Č!ĕĩŅĭ TTTT J>ĳ

J>b ĕ ĕĩ5c4ĳ000 T T Problem-word in example (11) is “ !ĕĩŅĭ ” and its T , correct form is “ !ĕfĲČ5ĭ ”. This issue is often found in words “ 9 ”, “ 9 ”, “ 9 ” T Another problem occurs with the persio-arabic and “ / ”. First three in pronunciations produce [e] )ő words with “ O” sound. When “ O” is followed by [u] sound that’s why they are written with “ č”. However, (ُ ) sound, they are mostly written with short vowel / the pronoun “ )ő ” is exception. It has been found in two (equivalent of Pesh) in Hindi text. This issue is different writing styles in today’s Hindi text i.e. “ őő ” discussed in detail in 3.2.2

and “ ” which is transliterated form of “ ” and čő (12) “ ”. / //// / 8:$ĕč4>ĳ<0:T 5=P 0ńŃĳ

3.2.2. Short vowel for Vao. Words adopted by Hindi 3.3. Multi-morphemes without space speakers from Urdu (Persio-Arabic) vocabulary have with short vowel pesh If we analyze Hindi text we would find out frequent ”و “ issues like wrong marking of This problem does not occur for all instances of use of multi-morphemes words. These words are .(◌ ُ) vao in Urdu. typically associated with the different problem-groups. Below we have discussed these groups and have morphologically correlated Hindi and Urdu grammars. (9) ? //// d:d:Ĵ: ĕ>

28 Proceedings of the Conference on Language & Technology 2009

3.3.1. Case markers after pronouns (+ 'sab'). In Hindi and Urdu sentence structures we use case In example (16) “ 4hŅ ” is problem-word in which markers. These markers can be identified “4 ” has been connected with “ m ” and this association grammatically as non-semantic prepositions. In Hindi has created new form of word which is neither a part of text, these case markers when use with the pronouns Urdu word list nor familiar for Urdu readers. disowns their individual form and coalesce with the 3.3.4. Compound words pronoun. . Urdu language has compound words in its vocabulary. These words are (13) ? based on multiple constituent words. These constituent //// words when written in compound form give new Ĵ5ńhĒJ>ĩ.5ńN<ŅĭT 0?ņ essence to the word. In Urdu, the general rule of In (13) case marker “ 0. ” is joined with a pronoun writing compound word is to put space among the / “< ”. Nevertheless, the word “ iĵ ” is not a pronoun constituents however Hindi writers usually don’t follow but it also follows the same principle. Hindi writers this convention; they write it by connecting the also write it in conjunction with the case markers. This constituents together. is illustrated by the example in (14): (17) (14) 0:5jJ>ĳĕń1Ň Čŋ5ĳ4ČĒĕ D0ŇNĵ 0:5:ŋ4A>kĕ 0ĵ5 ĕ 48ŁŅ>5.Čŋ T

In the above example, “ 0ŇNĵ ” has subjected to the Urdu glossary contains compound word “ A> ĕ ” unnecessary joining. which is consisted of two consitutents. As we can see in

(17) these constituents are merged together hence 3.3.2. gaa / gii / ge after verb. Hindi and Urdu generated new construction for the same compound grammar share the same auxiliaries to define aspect word: “ ”. and tense. In Urdu language, auxiliaries and basic- A>kĕ verbs are written standalone; however, in Hindi text the verbs are concatenated with the future auxiliaries 3.4. Difference in vocabulary “gaa”, “gii” and “ge”. Although both languages share a lot of words that includes native (Indian), Arabic, Persian, and English (15) ? loanwords but still Hindi and Urdu words differ at / , Ĵ5l>hĵ ĕkĩ0ńŃĳ5?1ď4>ĳĎČĕ> some places because one is using the words having Arabic or Persian origion while other is using the The verb “ ” in (15) is followed by the future Sanskrit loanwords. Differences have been noticed in a 0hĵ close class words and also in a general vocabulary. marker “ 5 ”. These two are written as a single word i.e. “ 5l>hĵ ” and Urdu speakers are mostly not familiar Table 6: Examples of difference in vocabulary with this form of the verb. in Urdu and Hindi

3.3.3. kar/ke after verb. Both Hindi and Urdu Close Class Words Open Class Words languages include conjunctions. These conjunctions Hindi Urdu Hindi Urdu ر اِِ دوارا are basically used to join two words or phrases را و رن together. Urdu language considers these conjunctions as individual word forms thus they are written separately. While in Hindi content conjunctions “kar” / There is a difference in the use of pronoun “ ”. In and “ke” are joined with the preceding verb. )ő Urdu, it is used for both singular and plural. But in / Hindi “ ” is used for third person singular and “ ” is )ő čő (16) used as third person plural. 0:5* 8>$ĕč4>ĳ4hŅ Ēĕ4ńT

29 Proceedings of the Conference on Language & Technology 2009

4. Proposed solutions successfully matched in their respective list, a space will be inserted between verb and conjunction. We have listed all those problems in section (3) It is important to note that we need a list of only the which we came across during transliteration process. root form of the verbs because kar/ke comes only with Now we present the solution of these problems. We the root form of the verb. For instance, aa-kar is propose to use the available system i.e. CRULP’s correct, but aaye-kar is not. Hindi to Urdu transliterator as part of the solution. We introduce pre-processing (on Hindi text before 4.1.3. gaa / gii / ge after verb. We discussed the issue transliteration) and post processing (on transliterated of future marker in section 3.3.2. This issue is only Urdu text) to get better transliteration. related to the verbs in subjunctive form e.g. J>Y* , J>Yĕ , The enhancements that are required to construct an . To resolve it, we require a list of subjunctive improved transliteration system are given below. J>Yĕń form of the verbs to detach a verb from auxiliaries’ ĕ 4.1 Multi-morphemes without space 5 0 . We need list of subjunctive verb because parhen-ge is As presented in 3.3 and 3.2.3, there are multi- being used in both languages, but parhte-ge is not. The morpheme words that are written without space in solution of this issue will follow the same matching Hindi, but in Urdu there is a space between the technique as described in 4.1.1 and 4.1.2 morphemes of these words. We need a solution that introduces the required space in transliterated Urdu 4.1.4. Multi-morphemes. To disambiguate multi- word. morphemes words that are written without space in We are presenting the solution which can intensify Hindi, we will maintain a list of compound words. For transliteration result using operational systems. For the creating this list we will select all the words from the problem-groups discussed below, we will apply available word list which have space among proposed techniques on transliterated text i.e. on Urdu constituents. We will then remove all the spaces in lexicon. between a compound word and will put the word without spaces and word with spaces in newly created 4.1.1. Case markers after pronouns (+ 'sab'). To compound words-list. solve the issues presented in 3.3.1, we will maintain a The transliterated word will be searched in the separate list of pronouns, case markers and exception compound words-list, having both forms of the word; if words discussed earlier to identify words that are a word matches with any entry in the list, the joined with the case markers. To distinguish those corresponding original compound word with spaces words we will perform a character by character will be returned. matching and as soon as a group of characters matches with any of the pronoun in the pronoun list we start 4.2. Word to word mapping checking for the remaining part of the word in a case markers list. If it matches successfully with any of the In the above section, we introduced the solutions in case marker in the list, both words gets splitted. which we can find the need of a missing space in transliterated Urdu text using different kind of a word Čŋĕņ: = <: o ČŋČ (don’t break) lists. This approach solves many problems, but there = (break) are remaining set of problems which do not have 0?ņ: <: o 0. generalized solutions. These problems need a simple word to word mapping between Hindi words and Urdu 4.1.2. kar/ke after verb. To classify verbs that are equivalents. written in merged form with the conjunctions (as In a word to word mapping we get wrong discussed in 3.3.3), we need to maintain a separate list transliteration because of the words that have different of verbs in the root form e.g. “chal”, “aa”, “parh” etc. spellings in both languages. Solution to this problem is We will have a root-verb-conjunction list too that will to maintain a list of words that differ in spelling in both have two words “kar” and “ke”. We will start with languages. This list will contain a proper Urdu lexicon character by character matching of the word in verb against each Hindi word. Before transliteration we will list; if we find a match for the verb initially then we map a word in the list, if a list contain that word, Urdu start comparing rest of the characters in conjunction word with proper transliteration already defined in the list. If both of these character groups of the word are list against problem-word will be selected and

30 Proceedings of the Conference on Language & Technology 2009 transliteration process will not be carried out for that 6. Acknowledgement particular word. This method will solve the issues introduced in The authors are thankful to Tikaram Poudel for his 3.2.1 (partially), 3.2.2 and 3.2.3 (partially). help in analysis of Hindi script and identification of problems. 4.3. Problems to be solved 7. References The problem of same sound characters needs extensive efforts. The problem can be solved by [1] Hindi to Urdu Transliterator , Center for Research in generating all possible transliterations of the Hindi Urdu Language Processing (CRULP), Lahore. word having same sound characters. These candidate Available:http://crulp.org/software/langproc/h2utranslite transliterations will be matched with a Hindi word list. rator.html We are not proposing the details of this solution here, but one can give an algorithm similar to “roman to [2] Malik, M. G. Abbas, Hindi Urdu Machine Urdu transliteration using word list” algorithm Transliteration System , MS thesis, Department of presented in the same conference [7]. Linguistics, University of Paris 7, Paris, 2006. We can not find the optimal solution of 3.1.4 i.e. [3] BBC Hindi website. kasr-e-izafat problem. This problem can be partially Available: http://www.bbc.co.uk/hindi/ solved through compound-word-list approach given in 4.1.4. It is observed that an average Hindi speaker use [4] T. Afroze, A door into Hindi , website, North Carolina very few words that have kasr-e-izafat. It is not State University, Raleigh NC. productive in Hindi and usually new words and phrases Available: http://taj.chass.ncsu.edu are not constructed by using kasr-e-izafat in Hindi. It is highly probable that if a Hindi writer used a [5] Devnagri Script, website. word having kasr-e-izafat, it will be in an Urdu Available: http://www.haryana-online.com/devnagri.htm lexicon. If the lexicon has spelling/pronunciation too like [8], we can make a list of the compound words [6] Urdu , website. having two words and an izafat between them. If any Available: http://www.haryana-online.com/urdu.htm transliterated Hindi word ends on bari-ye then the "word-space-next word" will be searched in the izafat- [7] T. Ahmed,. “Roman to Urdu transliteration using compound-word-list, if found then the word from the wordlist”, submitted to Conference of Language and izafat-compound-word list will be the output. Technology 2009 , Lahore, 2009. Vocabulary is still a problem, as Urdu readers are [8] Urdu Online Dictionary, website. not aware of all the words (specially the Sanskrit Available: http://www.crulp.org/oud/default.aspx words) that are used in Hindi.

5. Conclusion

After reviewing the output of existing Hindi to Urdu transliteration system, we find that there are issues that are still needed to be solved. The main issues for a better transliteration are: slight difference in both languages script, difference in spelling of the same words due to unawareness with correct form or due to diverse writing style, alteration in original forms of the words (commonly being used by both languages chroniclers) due to variation in a pronunciation of the words. We suggested post processing of the transliterator output and solved issues caused by writing convention differences, by consulting specific word lists.