utils/g2p/arabic.py

#!/usr/bin/python
# -*- coding: UTF8 -*-

# adapted from: https://github.com/nawarhalabi/Arabic-Phonetiser/blob/master/phonetise-Buckwalter.py
# license: Creative Commons Attribution-NonCommercial 4.0 International License.
# https://creativecommons.org/licenses/by-nc/4.0/

import re

arabic_to_buckw_dict = {  # mapping from Arabic script to Buckwalter
    u'\u0628': u'b', u'\u0630': u'*', u'\u0637': u'T', u'\u0645': u'm',
    u'\u062a': u't', u'\u0631': u'r', u'\u0638': u'Z', u'\u0646': u'n',
    u'\u062b': u'^', u'\u0632': u'z', u'\u0639': u'E', u'\u0647': u'h',
    u'\u062c': u'j', u'\u0633': u's', u'\u063a': u'g', u'\u062d': u'H',
    u'\u0642': u'q', u'\u0641': u'f', u'\u062e': u'x', u'\u0635': u'S',
    u'\u0634': u'$', u'\u062f': u'd', u'\u0636': u'D', u'\u0643': u'k',
    u'\u0623': u'>', u'\u0621': u'\'', u'\u0626': u'}', u'\u0624': u'&',
    u'\u0625': u'<', u'\u0622': u'|', u'\u0627': u'A', u'\u0649': u'Y',
    u'\u0629': u'p', u'\u064a': u'y', u'\u0644': u'l', u'\u0648': u'w',
    u'\u064b': u'F', u'\u064c': u'N', u'\u064d': u'K', u'\u064e': u'a',
    u'\u064f': u'u', u'\u0650': u'i', u'\u0651': u'~', u'\u0652': u'o'
}

buckw_to_arabic_dict = {  # mapping from Buckwalter to Arabic script
    u'b': u'\u0628', u'*': u'\u0630', u'T': u'\u0637', u'm': u'\u0645',
    u't': u'\u062a', u'r': u'\u0631', u'Z': u'\u0638', u'n': u'\u0646',
    u'^': u'\u062b', u'z': u'\u0632', u'E': u'\u0639', u'h': u'\u0647',
    u'j': u'\u062c', u's': u'\u0633', u'g': u'\u063a', u'H': u'\u062d',
    u'q': u'\u0642', u'f': u'\u0641', u'x': u'\u062e', u'S': u'\u0635',
    u'$': u'\u0634', u'd': u'\u062f', u'D': u'\u0636', u'k': u'\u0643',
    u'>': u'\u0623', u'\'': u'\u0621', u'}': u'\u0626', u'&': u'\u0624',
    u'<': u'\u0625', u'|': u'\u0622', u'A': u'\u0627', u'Y': u'\u0649',
    u'p': u'\u0629', u'y': u'\u064a', u'l': u'\u0644', u'w': u'\u0648',
    u'F': u'\u064b', u'N': u'\u064c', u'K': u'\u064d', u'a': u'\u064e',
    u'u': u'\u064f', u'i': u'\u0650', u'~': u'\u0651', u'o': u'\u0652'
}


def arabic_to_buckwalter(word):  # Convert input string to Buckwalter
    res = ''
    for letter in word:
        if(letter in arabic_to_buckw_dict):
            res += arabic_to_buckw_dict[letter]
        else:
            res += letter
    return res


def buckwalter_to_arabic(word):  # Convert input string to Arabic
    res = ''
    for letter in word:
        if(letter in buckw_to_arabic_dict):
            res += buckw_to_arabic_dict[letter]
        else:
            res += letter
    return res


# ----------------------------------------------------------------------------
# Grapheme to Phoneme mappings------------------------------------------------
# ----------------------------------------------------------------------------
unambiguousConsonantMap = {
    u'b': u'b', u'*': u'*', u'T': u'T', u'm': u'm',
    u't': u't', u'r': u'r', u'Z': u'Z', u'n': u'n',
    u'^': u'^', u'z': u'z', u'E': u'E', u'h': u'h',
    u'j': u'j', u's': u's', u'g': u'g', u'H': u'H',
    u'q': u'q', u'f': u'f', u'x': u'x', u'S': u'S',
    u'$': u'$', u'd': u'd', u'D': u'D', u'k': u'k',
    u'>': u'<', u'\'': u'<', u'}': u'<', u'&': u'<',
    u'<': u'<'
}

ambiguousConsonantMap = {
    # These consonants are only unambiguous in certain contexts
    u'l': [u'l', u''], u'w': u'w', u'y': u'y', u'p': [u't', u'']
}

maddaMap = {
    u'|': [[u'<', u'aa'], [u'<', u'AA']]
}

vowelMap = {
    u'A': [[u'aa', u''], [u'AA', u'']], u'Y': [[u'aa', u''], [u'AA', u'']],
    u'w': [[u'uu0', u'uu1'], [u'UU0', u'UU1']],
    u'y': [[u'ii0', u'ii1'], [u'II0', u'II1']],
    u'a': [u'a', u'A'],
    u'u': [[u'u0', u'u1'], [u'U0', u'U1']],
    u'i': [[u'i0', u'i1'], [u'I0', u'I1']],
}

nunationMap = {
    u'F': [[u'a', u'n'], [u'A', u'n']], u'N': [[u'u1', u'n'], [u'U1', u'n']], u'K': [[u'i1', u'n'], [u'I1', u'n']]
}

diacritics = [u'o', u'a', u'u', u'i', u'F', u'N', u'K', u'~']
diacriticsWithoutShadda = [u'o', u'a', u'u', u'i', u'F', u'N', u'K']
emphatics = [u'D', u'S', u'T', u'Z', u'g', u'x', u'q']
forwardEmphatics = [u'g', u'x']
consonants = [u'>', u'<', u'}', u'&', u'\'', u'b', u't', u'^', u'j', u'H', u'x', u'd', u'*', u'r',
              u'z', u's', u'$', u'S', u'D', u'T', u'Z', u'E', u'g', u'f', u'q', u'k', u'l', u'm', u'n', u'h', u'|']

# ------------------------------------------------------------------------------------
# Words with fixed irregular pronunciations-------------------------------------------
# ------------------------------------------------------------------------------------
fixedWords = {
    u'h*A': [u'h aa * aa', u'h aa * a', ],
    u'h*h': [u'h aa * i0 h i0', u'h aa * i1 h'],
    u'h*An': [u'h aa * aa n i0', u'h aa * aa n'],
    u'h&lA\'': [u'h aa < u0 l aa < i0', u'h aa < u0 l aa <'],
    u'*lk': [u'* aa l i0 k a', u'* aa l i0 k'],
    u'k*lk': [u'k a * aa l i0 k a', u'k a * aa l i1 k'],
    u'*lkm': u'* aa l i0 k u1 m',
    u'>wl}k': [u'< u0 l aa < i0 k a', u'< u0 l aa < i1 k'],
    u'Th': u'T aa h a',
    u'lkn': [u'l aa k i0 nn a', u'l aa k i1 n'],
    u'lknh': u'l aa k i0 nn a h u0',
    u'lknhm': u'l aa k i0 nn a h u1 m',
    u'lknk': [u'l aa k i0 nn a k a', u'l aa k i0 nn a k i0'],
    u'lknkm': u'l aa k i0 nn a k u1 m',
    u'lknkmA': u'l aa k i0 nn a k u0 m aa',
    u'lknnA': u'l aa k i0 nn a n aa',
    u'AlrHmn': [u'rr a H m aa n i0',  u'rr a H m aa n'],
    u'Allh': [u'll aa h i0', u'll aa h', u'll AA h u0', u'll AA h a', u'll AA h', u'll A'],
    u'h*yn': [u'h aa * a y n i0', u'h aa * a y n'],

    u'nt': u'n i1 t',
    u'fydyw': u'v i0 d y uu1',
    u'lndn': u'l A n d u1 n'
}


def isFixedWord(word, results, orthography, pronunciations):
    lastLetter = ''
    if(len(word) > 0):
        lastLetter = word[-1]
    if(lastLetter == u'a'):
        lastLetter = [u'a', u'A']
    elif(lastLetter == u'A'):
        lastLetter = [u'aa']
    elif(lastLetter == u'u'):
        lastLetter = [u'u0']
    elif(lastLetter == u'i'):
        lastLetter = [u'i0']
    elif(lastLetter in unambiguousConsonantMap):
        lastLetter = [unambiguousConsonantMap[lastLetter]]
    # Remove all dacritics from word
    wordConsonants = re.sub(u'[^h*Ahn\'>wl}kmyTtfd]', '', word)
    if(wordConsonants in fixedWords):  # check if word is in the fixed word lookup table
        if(isinstance(fixedWords[wordConsonants], list)):
            for pronunciation in fixedWords[wordConsonants]:
                if(pronunciation.split(' ')[-1] in lastLetter):
                    # add each pronunciation to the pronunciation dictionary
                    results += word + ' ' + pronunciation + '\n'
                    pronunciations.append(pronunciation.split(' '))
        else:
            # add pronunciation to the pronunciation dictionary
            results += word + ' ' + fixedWords[wordConsonants] + '\n'
            pronunciations.append(fixedWords[wordConsonants].split(' '))
    return results


def preprocess_utterance(utterance):
    # Do some normalisation work and split utterance to words
    utterance = utterance.replace(u'AF', u'F')
    utterance = utterance.replace(u'\u0640', u'')
    utterance = utterance.replace(u'o', u'')
    utterance = utterance.replace(u'aA', u'A')
    utterance = utterance.replace(u'aY', u'Y')
    utterance = utterance.replace(u' A', u' ')
    utterance = utterance.replace(u'F', u'an')
    utterance = utterance.replace(u'N', u'un')
    utterance = utterance.replace(u'K', u'in')
    utterance = utterance.replace(u'|', u'>A')

    utterance = utterance.replace('i~', '~i') 
    utterance = utterance.replace('a~', '~a') 
    utterance = utterance.replace('u~', '~u')

    utterance = utterance.replace('lA~a', 'l~aA')

    # Deal with Hamza types that when not followed by a short vowel letter,
    # this short vowel is added automatically
    utterance = re.sub(u'Ai', u'<i', utterance)
    utterance = re.sub(u'Aa', u'>a', utterance)
    utterance = re.sub(u'Au', u'>u', utterance)
    utterance = re.sub(u'^>([^auAw])', u'>a\\1', utterance)
    utterance = re.sub(u' >([^auAw ])', u' >a\\1', utterance)
    utterance = re.sub(u'<([^i])', u'<i\\1', utterance)
    utterance = utterance.split(u' ')

    return utterance


def process_word(word):

    pronunciations = []  # Start with empty set of possible pronunciations of current word
    # Add fixed irregular pronuncations if possible
    isFixedWord(word, '', word, pronunciations)

    # Indicates whether current character is in an emphatic context or not. Starts with False
    emphaticContext = False
    # This is the end/beginning of word symbol. just for convenience
    word = u'bb' + word + u'ee'

    phones = []  # Empty list which will hold individual possible word's pronunciation

    # -----------------------------------------------------------------------------------
    # MAIN LOOP: here is where the Modern Standard Arabic phonetisation rule-set starts--
    # -----------------------------------------------------------------------------------
    for index in range(2, len(word) - 2):
        letter = word[index]  # Current Character
        letter1 = word[index + 1]  # Next Character
        letter2 = word[index + 2]  # Next-Next Character
        letter_1 = word[index - 1]  # Previous Character
        letter_2 = word[index - 2]  # Before Previous Character
        # ----------------------------------------------------------------------------------------------------------------
        if(letter in consonants + [u'w', u'y'] and not letter in emphatics + [u'r'""", u'l'"""]):  # non-emphatic consonants (except for Lam and Ra) change emphasis back to False
            emphaticContext = False
        if(letter in emphatics):  # Emphatic consonants change emphasis context to True
            emphaticContext = True
        # If following letter is backward emphatic, emphasis state is set to True
        if(letter1 in emphatics and not letter1 in forwardEmphatics):
            emphaticContext = True
        # ----------------------------------------------------------------------------------------------------------------
        # ----------------------------------------------------------------------------------------------------------------
        # Unambiguous consonant phones. These map to a predetermined phoneme
        if(letter in unambiguousConsonantMap):
            phones += [unambiguousConsonantMap[letter]]
        # ----------------------------------------------------------------------------------------------------------------
        if(letter == u'l'):  # Lam is a consonant which requires special treatment
            # Lam could be omitted in definite article (sun letters)
            if((not letter1 in diacritics and not letter1 in vowelMap) and letter2 in [u'~']):
                phones += [ambiguousConsonantMap[u'l'][1]]  # omit
            else:
                # do not omit
                phones += [ambiguousConsonantMap[u'l'][0]]
        # ----------------------------------------------------------------------------------------------------------------
        # shadda just doubles the letter before it
        if(letter == u'~' and not letter_1 in [u'w', u'y'] and len(phones) > 0):
            phones[-1] += phones[-1]
        # ----------------------------------------------------------------------------------------------------------------
        if(letter == u'|'):  # Madda only changes based in emphaticness
            if(emphaticContext):
                phones += [maddaMap[u'|'][1]]
            else:
                phones += [maddaMap[u'|'][0]]
        # ----------------------------------------------------------------------------------------------------------------
        if(letter == u'p'):  # Ta' marboota is determined by the following if it is a diacritic or not
            if(letter1 in diacritics):
                phones += [ambiguousConsonantMap[u'p'][0]]
            else:
                phones += [ambiguousConsonantMap[u'p'][1]]
        # ----------------------------------------------------------------------------------------------------------------
        if(letter in vowelMap):
            # Waw and Ya are complex they could be consonants or vowels and their gemination is complex as it could be a combination of a vowel and consonants
            if(letter in [u'w', u'y']):
                if(letter1 in diacriticsWithoutShadda + [u'A', u'Y'] or (letter1 in [u'w', u'y'] and not letter2 in diacritics + [u'A', u'w', u'y']) or (letter_1 in diacriticsWithoutShadda and letter1 in consonants + [u'e'])):
                    if((letter in [u'w'] and letter_1 in [u'u'] and not letter1 in [u'a', u'i', u'A', u'Y']) or (letter in [u'y'] and letter_1 in [u'i'] and not letter1 in [u'a', u'u', u'A', u'Y'])):
                        if(emphaticContext):
                            phones += [vowelMap[letter][1][0]]
                        else:
                            phones += [vowelMap[letter][0][0]]
                    else:
                        if(letter1 in [u'A'] and letter in [u'w'] and letter2 in [u'e']):
                            phones += [[ambiguousConsonantMap[letter],
                                        vowelMap[letter][0][0]]]
                        else:
                            phones += [ambiguousConsonantMap[letter]]
                elif(letter1 in [u'~']):
                    if(letter_1 in [u'a'] or (letter in [u'w'] and letter_1 in [u'i', u'y']) or (letter in [u'y'] and letter_1 in [u'w', u'u'])):
                        phones += [ambiguousConsonantMap[letter],
                                   ambiguousConsonantMap[letter]]
                    else:
                        phones += [vowelMap[letter][0][0],
                                   ambiguousConsonantMap[letter]]
                else:  # Waws and Ya's at the end of the word could be shortened
                    if(emphaticContext):
                        if(letter_1 in consonants + [u'u', u'i'] and letter1 in [u'e']):
                            phones += [[vowelMap[letter][1]
                                        [0], vowelMap[letter][1][0][1:]]]
                        else:
                            phones += [vowelMap[letter][1][0]]
                    else:
                        if(letter_1 in consonants + [u'u', u'i'] and letter1 in [u'e']):
                            phones += [[vowelMap[letter][0]
                                        [0], vowelMap[letter][0][0][1:]]]
                        else:
                            phones += [vowelMap[letter][0][0]]
            # Kasra and Damma could be mildened if before a final silent consonant
            if(letter in [u'u', u'i']):
                if(emphaticContext):
                    if((letter1 in unambiguousConsonantMap or letter1 == u'l') and letter2 == u'e' and len(word) > 7):
                        phones += [vowelMap[letter][1][1]]
                    else:
                        phones += [vowelMap[letter][1][0]]
                else:
                    if((letter1 in unambiguousConsonantMap or letter1 == u'l') and letter2 == u'e' and len(word) > 7):
                        phones += [vowelMap[letter][0][1]]
                    else:
                        phones += [vowelMap[letter][0][0]]
            # Alif could be ommited in definite article and beginning of some words
            if(letter in [u'a', u'A', u'Y']):
                if(letter in [u'A'] and letter_1 in [u'w', u'k'] and letter_2 == u'b'):
                    phones += [[u'a', vowelMap[letter][0][0]]]
                elif(letter in [u'A'] and letter_1 in [u'u', u'i']):
                    temp = True  # do nothing
                # Waw al jama3a: The Alif after is optional
                elif(letter in [u'A'] and letter_1 in [u'w'] and letter1 in [u'e']):
                    phones += [[vowelMap[letter][0]
                                [0], vowelMap[letter][0][1]]]
                elif(letter in [u'A', u'Y'] and letter1 in [u'e']):
                    if(emphaticContext):
                        phones += [[vowelMap[letter]
                                    [1][0], vowelMap[u'a'][1]]]
                    else:
                        phones += [[vowelMap[letter]
                                    [0][0], vowelMap[u'a'][0]]]
                else:
                    if(emphaticContext):
                        phones += [vowelMap[letter][1][0]]
                    else:
                        phones += [vowelMap[letter][0][0]]
    # -------------------------------------------------------------------------------------------------------------------------
    # End of main loop---------------------------------------------------------------------------------------------------------
    # -------------------------------------------------------------------------------------------------------------------------
    possibilities = 1  # Holds the number of possible pronunciations of a word

    # count the number of possible pronunciations
    for letter in phones:
        if(isinstance(letter, list)):
            possibilities = possibilities * len(letter)

    # Generate all possible pronunciations
    for i in range(0, possibilities):
        pronunciations.append([])
        iterations = 1
        for index, letter in enumerate(phones):
            if(isinstance(letter, list)):
                curIndex = int(i / iterations) % len(letter)
                if(letter[curIndex] != u''):
                    pronunciations[-1].append(letter[curIndex])
                iterations = iterations * len(letter)
            else:
                if(letter != u''):
                    pronunciations[-1].append(letter)

    # Iterate through each pronunciation to perform some house keeping. And append pronunciation to dictionary
    # 1- Remove duplicate vowels
    # 2- Remove duplicate y and w
    for pronunciation in pronunciations:
        prevLetter = ''
        toDelete = []
        for i in range(0, len(pronunciation)):
            letter = pronunciation[i]
            # Delete duplicate consecutive vowels
            if(letter in ['aa', 'uu0', 'ii0', 'AA', 'UU0', 'II0'] and prevLetter.lower() == letter[1:].lower()):
                toDelete.append(i - 1)
                pronunciation[i] = pronunciation[i -
                                                 1][0] + pronunciation[i - 1]
            # Delete duplicates
            if(letter in ['u0', 'i0'] and prevLetter.lower() == letter.lower()):
                toDelete.append(i - 1)
                pronunciation[i] = pronunciation[i - 1]
            if(letter in ['y', 'w'] and prevLetter == letter):  # delete duplicate
                pronunciation[i - 1] += pronunciation[i - 1]
                toDelete.append(i)

            prevLetter = letter
        for i in reversed(range(0, len(toDelete))):
            del(pronunciation[toDelete[i]])

    return pronunciations[0]


def process_utterance(utterance):

    utterance = preprocess_utterance(utterance)
    phonemes = []

    for word in utterance:
        if(word in ['-', 'sil']):
            phonemes.append(['sil'])
            continue

        phonemes_word = process_word(word)
        phonemes.append(phonemes_word)

    final_sequence = ' + '.join(' '.join(phon for phon in phones)
                                for phones in phonemes)

    return final_sequence