import os import io import subprocess import numpy as np from difflib import SequenceMatcher from datetime import datetime from typing import List, Tuple, Dict import asyncio import base64 import string import re import urllib.request import gzip import tempfile # Set cache environment os.environ['HF_HOME'] = '/tmp/hf' os.environ['TORCH_HOME'] = '/tmp/torch' os.environ['TRANSFORMERS_CACHE'] = '/tmp/hf' os.environ['XDG_CACHE_HOME'] = '/tmp/hf' os.environ['MPLCONFIGDIR'] = '/tmp/matplotlib' # Fix matplotlib permission issue os.environ['PULSE_CONFIG_PATH'] = '/tmp/pulse' # Fix PulseAudio errors os.environ['PULSE_RUNTIME_PATH'] = '/tmp/pulse' os.makedirs('/tmp/hf', exist_ok=True) os.makedirs('/tmp/torch', exist_ok=True) os.makedirs('/tmp/matplotlib', exist_ok=True) os.makedirs('/tmp/pulse', exist_ok=True) from fastapi import FastAPI, UploadFile, File, Form from fastapi.middleware.cors import CORSMiddleware import torchaudio import torch from phonemizer import phonemize import whisperx # New: WhisperX for precise alignment from transformers import Wav2Vec2Processor, Wav2Vec2ForCTC import edge_tts def log(msg): print(f"[{datetime.now().strftime('%H:%M:%S')}] {msg}") app = FastAPI() app.add_middleware(CORSMiddleware, allow_origins=["*"], allow_credentials=True, allow_methods=["*"], allow_headers=["*"]) def normalize_phoneme_string(s: str) -> str: """Normalize phoneme string for comparison - remove spaces and extra chars""" if not s: return s # Convert to lowercase and remove spaces, stress marks, and length markers normalized = s.lower().strip() normalized = normalized.replace(' ', '') # Remove spaces between phonemes normalized = normalized.replace('ː', '') # Remove length markers normalized = normalized.replace('ˈ', '') # Remove primary stress normalized = normalized.replace('ˌ', '') # Remove secondary stress normalized = normalized.replace('.', '') # Remove syllable boundaries # CRITICAL: Explode affricate ligatures into their component parts # These single-character affricates need to be expanded to match decomposed forms affricate_ligatures = { 'ʧ': 'tʃ', # Voiceless postalveolar affricate (chip) 'ʤ': 'dʒ', # Voiced postalveolar affricate (jump) 'ʦ': 'ts', # Voiceless alveolar affricate (German Zeit) 'ʣ': 'dz', # Voiced alveolar affricate (Italian mezzo) 'ʨ': 'tɕ', # Voiceless alveolo-palatal affricate (Polish ć) 'ʥ': 'dʑ', # Voiced alveolo-palatal affricate (Polish dź) 'ƛ': 'tɬ', # Voiceless alveolar lateral affricate (Nahuatl tl) 'ꜩ': 'tɕ', # Variant for voiceless alveolo-palatal affricate } for ligature, expanded in affricate_ligatures.items(): normalized = normalized.replace(ligature, expanded) # CRITICAL: Normalize ASCII symbols to proper IPA equivalents # Convert all wav2vec2 ASCII characters to standard IPA ascii_to_ipa = { 'g': 'ɡ', # ASCII g → IPA script g (voiced velar stop) 'b': 'b', # ASCII b → IPA b (already correct, but explicit) 'd': 'd', # ASCII d → IPA d (already correct, but explicit) 'f': 'f', # ASCII f → IPA f (already correct, but explicit) 'h': 'h', # ASCII h → IPA h (already correct, but explicit) 'i': 'i', # ASCII i → IPA i (already correct, but explicit) # Note: Most ASCII phonetic chars are already valid IPA, except 'g' } # Normalize variant IPA symbols to consistent forms # Handle different representations of the same sounds ipa_variants = { 'ɜ': 'ɝ', # Open-mid central → r-colored (American English "er") 'ɚ': 'ɝ', # R-colored schwa → r-colored vowel (both "er" sounds) 'ʌ': 'ə', # Open-mid back → schwa (both unstressed "uh" sounds) 'ð': 'θ', # Voiced th → voiceless th (accent training - treat as equivalent) 'ɹ': 'r', # Retroflex approximant → regular r (espeak vs CMUdict difference) } for ascii_char, ipa_char in ascii_to_ipa.items(): normalized = normalized.replace(ascii_char, ipa_char) for variant_char, standard_char in ipa_variants.items(): normalized = normalized.replace(variant_char, standard_char) return normalized # Load models once at startup phoneme_processor = Wav2Vec2Processor.from_pretrained("vitouphy/wav2vec2-xls-r-300m-timit-phoneme") phoneme_model = Wav2Vec2ForCTC.from_pretrained("vitouphy/wav2vec2-xls-r-300m-timit-phoneme") # Model inspection complete - wav2vec2 uses ASCII 'g' (token 15), not IPA 'ɡ' log("✅ Phoneme models loaded - using ASCII/IPA normalization") # WhisperX models - loaded lazily whisperx_model = None whisperx_align_model = None whisperx_metadata = None # Simple caches phoneme_cache = {} tts_cache = {} # TTS configuration TTS_VOICE = "en-US-AriaNeural" # Phoneme to English letter sounds mapping PHONEME_TO_ENGLISH = { # Vowels (monophthongs) 'ɪ': 'IH', # "bit" 'ɛ': 'EH', # "bed" 'æ': 'AE', # "cat" 'ʌ': 'UH', # "but" 'ɑ': 'AH', # "father" 'ɔ': 'AW', # "law" 'ʊ': 'UU', # "book" 'u': 'OO', # "boot" 'i': 'EE', # "beat" 'ə': 'UH', # "about" (schwa) 'ɝ': 'ER', # "bird" 'ɚ': 'ER', # "letter" # Diphthongs 'eɪ': 'AY', # "day" 'aɪ': 'EYE', # "my" 'ɔɪ': 'OY', # "boy" 'aʊ': 'OW', # "now" 'oʊ': 'OH', # "go" # R-colored vowels 'ɪr': 'EER', # "near" 'ɛr': 'AIR', # "care" 'ɑr': 'AR', # "car" 'ɔr': 'OR', # "for" 'ʊr': 'OOR', # "tour" 'ər': 'ER', # "letter" 'ɚ': 'ER', # alternate schwa-r # Consonants 'p': 'P', # "pat" 'b': 'B', # "bat" 't': 'T', # "tap" 'd': 'D', # "dap" 'k': 'K', # "cat" 'g': 'G', # "gap" (wav2vec2 uses ASCII g) 'ɡ': 'G', # "gap" (IPA script g - normalize to same) 'f': 'F', # "fat" 'v': 'V', # "vat" 'θ': 'TH', # "think" 'ð': 'TH', # "this" 's': 'S', # "sap" 'z': 'Z', # "zap" 'ʃ': 'SH', # "ship" 'ʒ': 'ZH', # "measure" 'h': 'H', # "hat" 'm': 'M', # "mat" 'n': 'N', # "nat" 'ŋ': 'NG', # "sing" 'l': 'L', # "lap" 'r': 'R', # "rap" 'j': 'Y', # "yes" 'w': 'W', # "wet" # Affricates 'tʃ': 'CH', # "chip" 'dʒ': 'J', # "jump" # Common combinations that might appear ' ': '-', # space becomes dash 'ː': '', # length marker (remove) 'ˈ': '', # primary stress (remove) 'ˌ': '', # secondary stress (remove) } # Phoneme example words - showing the sound in context PHONEME_EXAMPLES = { # Vowels (monophthongs) 'ɪ': 'bit', # IH sound 'ɛ': 'bed', # EH sound 'æ': 'cat', # AE sound 'ʌ': 'but', # UH sound (stressed) 'ɑ': 'father', # AH sound 'ɔ': 'law', # AW sound 'ʊ': 'book', # UU sound 'u': 'boot', # OO sound 'i': 'beat', # EE sound 'ə': 'about', # schwa (unstressed) 'ɝ': 'bird', # ER sound (stressed) 'ɚ': 'letter', # ER sound (unstressed) # Diphthongs 'eɪ': 'day', # AY sound 'aɪ': 'my', # EYE sound 'ɔɪ': 'boy', # OY sound 'aʊ': 'now', # OW sound 'oʊ': 'go', # OH sound # R-colored vowels 'ɪr': 'near', # EER sound 'ɛr': 'care', # AIR sound 'ɑr': 'car', # AR sound 'ɔr': 'for', # OR sound 'ʊr': 'tour', # OOR sound 'ər': 'letter', # ER sound # Consonants 'p': 'pat', # P sound 'b': 'bat', # B sound 't': 'tap', # T sound 'd': 'dap', # D sound 'k': 'cat', # K sound 'g': 'gap', # G sound (ASCII) 'ɡ': 'gap', # G sound (IPA) 'f': 'fat', # F sound 'v': 'vat', # V sound 'θ': 'think', # TH sound (voiceless) 'ð': 'this', # TH sound (voiced) 's': 'sap', # S sound 'z': 'zap', # Z sound 'ʃ': 'ship', # SH sound 'ʒ': 'measure', # ZH sound 'h': 'hat', # H sound 'm': 'mat', # M sound 'n': 'nat', # N sound 'ŋ': 'sing', # NG sound 'l': 'lap', # L sound 'r': 'rap', # R sound 'j': 'yes', # Y sound 'w': 'wet', # W sound # Affricates 'tʃ': 'chip', # CH sound 'dʒ': 'jump', # J sound } def clean_word_for_phonemes(word: str) -> str: """ Clean word by removing punctuation and extra spaces for phoneme processing. Keeps only alphabetical characters. """ # Remove punctuation and extra whitespace cleaned = word.strip().translate(str.maketrans('', '', string.punctuation)) cleaned = ''.join(cleaned.split()) # Remove all whitespace log(f"Word cleaning: '{word}' → '{cleaned}'") return cleaned def convert_digits_to_words(text: str) -> str: """Convert digits to word form for better phoneme analysis""" # Dictionary for number conversion number_words = { '0': 'zero', '1': 'one', '2': 'two', '3': 'three', '4': 'four', '5': 'five', '6': 'six', '7': 'seven', '8': 'eight', '9': 'nine', '10': 'ten', '11': 'eleven', '12': 'twelve', '13': 'thirteen', '14': 'fourteen', '15': 'fifteen', '16': 'sixteen', '17': 'seventeen', '18': 'eighteen', '19': 'nineteen', '20': 'twenty', '30': 'thirty', '40': 'forty', '50': 'fifty', '60': 'sixty', '70': 'seventy', '80': 'eighty', '90': 'ninety', '100': 'one hundred', '1000': 'one thousand' } def convert_number(match): num_str = match.group() num = int(num_str) # Direct lookup for common numbers if num_str in number_words: return number_words[num_str] # Handle numbers 21-99 if 21 <= num <= 99: tens = (num // 10) * 10 ones = num % 10 if ones == 0: return number_words[str(tens)] else: return number_words[str(tens)] + " " + number_words[str(ones)] # Handle numbers 101-999 (basic implementation) if 101 <= num <= 999: hundreds = num // 100 remainder = num % 100 result = number_words[str(hundreds)] + " hundred" if remainder > 0: if remainder < 21: result += " " + number_words[str(remainder)] else: tens = (remainder // 10) * 10 ones = remainder % 10 result += " " + number_words[str(tens)] if ones > 0: result += " " + number_words[str(ones)] return result # For larger numbers or edge cases, return original return num_str # Replace standalone digits/numbers with word equivalents converted = re.sub(r'\b\d+\b', convert_number, text) log(f"Number conversion: '{text}' → '{converted}'") return converted def load_whisperx_models(): """Load WhisperX models lazily with English-only configuration""" global whisperx_model, whisperx_align_model, whisperx_metadata if whisperx_model is None: log("Loading WhisperX models for English-only processing...") # First, try to set environment variable to disable executable stack os.environ['LD_BIND_NOW'] = '1' try: # Try loading with base.en first whisperx_model = whisperx.load_model("base.en", device="cpu", compute_type="float32", language="en") log("WhisperX base.en model loaded successfully") # Load alignment model for English whisperx_align_model, whisperx_metadata = whisperx.load_align_model(language_code="en", device="cpu") log("WhisperX English alignment model loaded successfully") except ImportError as ie: log(f"Import error loading WhisperX models: {ie}") # Try to use regular Whisper as fallback try: log("Attempting to use standard Whisper instead of WhisperX...") import whisper # Load standard whisper model whisper_model = whisper.load_model("base.en", device="cpu") # Create a wrapper to make it compatible with WhisperX interface class WhisperWrapper: def __init__(self, model): self.model = model def transcribe(self, audio, batch_size=16, language="en"): result = self.model.transcribe(audio, language=language) # Convert to WhisperX format return { "segments": [{ "text": result["text"], "start": 0.0, "end": len(audio) / 16000.0, # Approximate based on sample rate "words": [] # Will need to handle word-level timing differently }], "language": language } whisperx_model = WhisperWrapper(whisper_model) log("Using standard Whisper as fallback (limited word-level timing)") # For alignment, we'll need to handle this differently whisperx_align_model = None whisperx_metadata = None except Exception as whisper_error: log(f"Standard Whisper fallback failed: {whisper_error}") # Last resort: Create a minimal mock that at least returns something class MinimalWhisperMock: def transcribe(self, audio, batch_size=16, language="en"): # Return a minimal valid structure return { "segments": [{ "text": "[Audio processing unavailable - WhisperX loading failed]", "start": 0.0, "end": 1.0, "words": [] }], "language": language } whisperx_model = MinimalWhisperMock() whisperx_align_model = None whisperx_metadata = None log("WARNING: Using minimal mock - transcription will be limited") except Exception as e: log(f"Error loading WhisperX models: {e}") raise RuntimeError(f"Unable to load speech recognition models: {e}") def convert_webm_to_wav(bts): p = subprocess.run(["ffmpeg", "-i", "pipe:0", "-f", "wav", "-ar", "16000", "-ac", "1", "pipe:1"], input=bts, stdout=subprocess.PIPE, stderr=subprocess.PIPE) if p.returncode != 0: raise RuntimeError(p.stderr.decode()) return io.BytesIO(p.stdout) def calculate_similarity(detected: str, expected: str) -> float: """Calculate similarity between detected and expected phonemes""" detected_norm = normalize_phoneme_string(detected) expected_norm = normalize_phoneme_string(expected) return SequenceMatcher(None, detected_norm, expected_norm).ratio() def detect_word_boundary_overlap(audio_segment: torch.Tensor, sample_rate: int, word: str) -> float: """ Analyze first 1/3 of audio segment for: [noise] → [silence] → [noise] pattern Returns: offset in seconds to skip initial noise, or 0.0 if no pattern found """ if audio_segment.shape[-1] == 0: return 0.0 # Analyze only first 1/3 of segment first_third_samples = audio_segment.shape[-1] // 3 if first_third_samples < sample_rate * 0.1: # Less than 100ms total return 0.0 first_third = audio_segment[:, :first_third_samples] # WORKAROUND: Audio segment appears to be reversed for unknown reason # This flip corrects the chronological order for proper boundary detection first_third = torch.flip(first_third, [-1]) # Calculate energy in small windows (50ms chunks) window_size = int(0.05 * sample_rate) # 50ms windows if window_size <= 0: return 0.0 energy_levels = [] for i in range(0, first_third_samples - window_size, window_size): window = first_third[:, i:i + window_size] energy = torch.mean(window ** 2).item() # RMS energy energy_levels.append(energy) if len(energy_levels) < 3: return 0.0 # Look for pattern: [high energy] → [low energy] → [high energy] silence_threshold = np.percentile(energy_levels, 20) # Bottom 20% noise_threshold = silence_threshold * 3 # Find sustained silence (2+ consecutive low-energy windows) for i in range(len(energy_levels) - 1): if (energy_levels[i] < silence_threshold and energy_levels[i + 1] < silence_threshold): # Check if there was noise before silence noise_before = any(e > noise_threshold for e in energy_levels[:i]) # Check if there's noise after silence noise_after = any(e > noise_threshold for e in energy_levels[i + 2:]) if noise_before and noise_after: # Found the pattern! Return offset to end of silence silence_end_sample = (i + 2) * window_size offset_seconds = silence_end_sample / sample_rate log(f"🔧 Word '{word}': detected boundary overlap, trimming {offset_seconds:.3f}s from start") return offset_seconds return 0.0 # No pattern detected def extract_audio_segment(waveform: torch.Tensor, sample_rate: int, start_time: float, end_time: float, word: str, verbose: bool = True) -> torch.Tensor: """Extract audio segment for a specific word""" # Convert to samples start_sample = int(start_time * sample_rate) end_sample = int(end_time * sample_rate) end_sample = min(waveform.shape[-1], end_sample) if end_sample <= start_sample: if verbose: log(f"Invalid segment for '{word}': {start_time:.3f}s-{end_time:.3f}s") return torch.zeros((1, 1600)) # Return 100ms of silence segment = waveform[:, start_sample:end_sample] if verbose: log(f"Extracted '{word}': {start_time:.3f}s-{end_time:.3f}s ({segment.shape[-1]} samples)") return segment def detect_phoneme_from_audio(audio_segment: torch.Tensor, sample_rate: int, word: str) -> str: """Detect phoneme from audio segment using phoneme model""" log(f"🔍 Starting phoneme detection for '{word}'...") if audio_segment.shape[-1] == 0: log(f"⚠️ Empty audio segment for '{word}'") return "" log(f"🔊 Original audio segment: {audio_segment.shape[-1]} samples") # Pad or truncate to standard length for model target_length = 16000 # 1 second if audio_segment.shape[-1] < target_length: log(f"🔧 Padding audio from {audio_segment.shape[-1]} to {target_length} samples") audio_segment = torch.nn.functional.pad(audio_segment, (0, target_length - audio_segment.shape[-1])) elif audio_segment.shape[-1] > target_length: # Don't truncate long segments - keep full audio for complex words log(f"⚠️ Audio longer than target ({audio_segment.shape[-1]} > {target_length}), keeping full length") log(f" This preserves all phonemes for long words like 'sophisticated'") else: log(f"✅ Audio segment already correct length: {target_length} samples") log(f"🎛️ Processing through phoneme processor...") start_time = datetime.now() # Process through phoneme model try: input_values = phoneme_processor(audio_segment.squeeze(), sampling_rate=sample_rate, return_tensors="pt").input_values processor_time = (datetime.now() - start_time).total_seconds() log(f"⏱️ Phoneme processor took: {processor_time:.3f}s") log(f"🧠 Running through phoneme model...") model_start_time = datetime.now() with torch.no_grad(): logits = phoneme_model(input_values).logits predicted_ids = torch.argmax(logits, dim=-1) detected_phoneme = phoneme_processor.decode(predicted_ids[0]) model_time = (datetime.now() - model_start_time).total_seconds() log(f"⏱️ Phoneme model inference took: {model_time:.3f}s") total_time = (datetime.now() - start_time).total_seconds() log(f"⏱️ Total phoneme detection time: {total_time:.3f}s") except Exception as e: log(f"❌ Error in phoneme detection: {e}") return "" log(f"🎯 Phoneme detection for '{word}': '{detected_phoneme}'") return detected_phoneme def sliding_window_phoneme_match(detected_phoneme: str, expected_phoneme: str, word: str) -> Tuple[str, float, int, int]: """ Find the best matching substring in detected phoneme using sliding window. For zero scores, intelligently selects which phoneme substring to return. Returns: (best_match_substring, best_score, start_index, end_index) """ detected_norm = normalize_phoneme_string(detected_phoneme) expected_norm = normalize_phoneme_string(expected_phoneme) log(f"🔍 Sliding window analysis for '{word}':") log(f" Expected (norm): '{expected_norm}' (length: {len(expected_norm)})") log(f" Detected (norm): '{detected_norm}' (length: {len(detected_norm)})") # If detected is shorter than expected, just compare directly if len(detected_norm) < len(expected_norm): score = calculate_similarity(detected_norm, expected_norm) log(f" Direct comparison (detected < expected): score = {score:.3f}") return detected_norm, score, 0, len(detected_norm) # Sliding window: detected is longer than expected expected_len = len(expected_norm) best_score = 0 best_match = "" best_start = 0 best_end = expected_len log(f" Sliding window search (window size: {expected_len}):") # Slide through all possible positions for i in range(len(detected_norm) - expected_len + 1): substring = detected_norm[i:i + expected_len] score = calculate_similarity(substring, expected_norm) log(f" Position {i}: '{substring}' vs '{expected_norm}' = {score:.3f}") if score > best_score: # Changed back from >= to > to prefer earlier matches best_score = score best_match = substring best_start = i best_end = i + expected_len log(f" ✅ New best match!") # Exit early on perfect match if score >= 1.0: log(f" 🎯 Perfect match found, stopping search") break # Handle zero score case - aim for middle substring when possible if best_score == 0: log(f" ⚠️ Zero score detected, selecting middle substring for audio alignment") total_detected_len = len(detected_norm) if total_detected_len == expected_len: # Same length - use the whole string best_start = 0 best_end = expected_len best_match = detected_norm log(f" 🔍 Same length: using full string") else: # Longer detected - aim for middle middle_start = max(0, (total_detected_len - expected_len) // 2) best_start = middle_start best_end = middle_start + expected_len best_match = detected_norm[best_start:best_end] log(f" 🔍 Aiming for middle: position {best_start}-{best_end}") log(f" 🏆 Final selection: '{best_match}' at position {best_start}-{best_end} (score: {best_score:.3f})") return best_match, best_score, best_start, best_end def create_word_phoneme_mapping_v2(word: str, expected_phoneme: str) -> Dict[int, str]: """ Create mapping from phoneme positions to original word letters. Simplified version that handles common cases more reliably. Args: word: The original word (already cleaned, no punctuation) expected_phoneme: The expected phoneme string Returns: Dictionary mapping phoneme index to word letter(s) """ word_lower = word.lower() phoneme_norm = normalize_phoneme_string(expected_phoneme) log(f"🗺️ Creating mapping for '{word}' → '{phoneme_norm}'") log(f" Word length: {len(word_lower)}, Phoneme length: {len(phoneme_norm)}") if not phoneme_norm: return {} # Simple cases first if len(word_lower) == len(phoneme_norm): # Direct 1:1 mapping mapping = {i: word[i] for i in range(len(phoneme_norm))} # Preserve original case log(f" Direct mapping (equal lengths): {mapping}") return mapping # For length mismatches, use proportional distribution mapping = {} if len(phoneme_norm) > len(word_lower): # More phonemes than letters (diphthongs, etc.) # Distribute letters across phonemes without duplication phonemes_per_letter = len(phoneme_norm) / len(word_lower) for phoneme_idx in range(len(phoneme_norm)): # Find which letter this phoneme belongs to letter_idx = min(int(phoneme_idx / phonemes_per_letter), len(word_lower) - 1) # Only assign each letter once (to its first phoneme) start_phoneme_for_letter = int(letter_idx * phonemes_per_letter) if phoneme_idx == start_phoneme_for_letter: mapping[phoneme_idx] = word[letter_idx] # Preserve case else: mapping[phoneme_idx] = '' # Empty for additional phonemes else: # More letters than phonemes (silent letters) # Distribute letters across available phonemes letters_per_phoneme = len(word_lower) / len(phoneme_norm) for phoneme_idx in range(len(phoneme_norm)): # Calculate range of letters for this phoneme start_letter = int(phoneme_idx * letters_per_phoneme) end_letter = int((phoneme_idx + 1) * letters_per_phoneme) # Collect all letters for this phoneme letter_group = word[start_letter:end_letter] mapping[phoneme_idx] = letter_group log(f" Final mapping: {mapping}") return mapping def create_character_level_feedback_v2(word: str, expected_norm: str, detected_norm: str, mapping: Dict[int, str]) -> str: """ Create character-level feedback with simplified logic. Args: word: Original word (for display purposes) expected_norm: Normalized expected phonemes detected_norm: Normalized detected phonemes mapping: Phoneme position to letter mapping Returns: HTML string with properly formatted feedback """ result = [] log(f"📝 Character feedback for '{word}':") log(f" Expected: '{expected_norm}' (len={len(expected_norm)})") log(f" Detected: '{detected_norm}' (len={len(detected_norm)})") # Ensure both strings are same length for comparison max_len = max(len(expected_norm), len(detected_norm)) expected_padded = expected_norm.ljust(max_len) detected_padded = detected_norm.ljust(max_len) # Track which word positions have been used used_positions = set() for i in range(min(len(expected_norm), max_len)): expected_char = expected_padded[i] if i < len(expected_padded) else ' ' detected_char = detected_padded[i] if i < len(detected_padded) else ' ' # Get the word letter(s) for this phoneme position word_letters = mapping.get(i, '') # Skip empty mappings (extra phonemes in diphthongs) if not word_letters: continue # Check if we've already used these letters letter_key = (word_letters, i) if letter_key in used_positions: continue used_positions.add(letter_key) if expected_char == detected_char: # Correct pronunciation - show original letters result.append(word_letters) else: # Incorrect - create error span with tooltip expected_english = PHONEME_TO_ENGLISH.get(expected_char, expected_char) expected_example = PHONEME_EXAMPLES.get(expected_char, '') detected_english = PHONEME_TO_ENGLISH.get(detected_char, 'silence' if detected_char == ' ' else detected_char) detected_example = PHONEME_EXAMPLES.get(detected_char, '') # Build tooltip text if expected_example and detected_example: tooltip = f"Expected '{expected_english}' as in '{expected_example}'
You said '{detected_english}' as in '{detected_example}'" elif expected_example: tooltip = f"Expected '{expected_english}' as in '{expected_example}'
You said '{detected_english}'" else: tooltip = f"Expected '{expected_english}'
You said '{detected_english}'" # Create error span error_html = f'{word_letters}' result.append(error_html) feedback = ''.join(result) log(f" Final feedback: {feedback}") return feedback def format_output_word_v2(word_original: str, word_clean: str, similarity_score: float, detected_phoneme: str, expected_phoneme: str, similarity_threshold: float) -> Tuple[str, str]: """ Format word output with cleaner logic. Args: word_original: Original word with punctuation (for display) word_clean: Cleaned word (for phoneme processing) similarity_score: Similarity score between detected and expected detected_phoneme: Detected phoneme string expected_phoneme: Expected phoneme string similarity_threshold: User's threshold for acceptable pronunciation Returns: Tuple of (display_text, colored_html) """ # Determine color based on score if similarity_score < similarity_threshold: color = "red" needs_feedback = True elif similarity_score >= similarity_threshold + (1.0 - similarity_threshold) * 0.3: color = "green" needs_feedback = False else: color = "orange" needs_feedback = False score_percentage = int(similarity_score * 100) if needs_feedback: # Poor pronunciation - show character-level feedback # Create phoneme mapping using cleaned word mapping = create_word_phoneme_mapping_v2(word_clean, expected_phoneme) # Normalize phonemes for comparison expected_norm = normalize_phoneme_string(expected_phoneme) detected_norm = normalize_phoneme_string(detected_phoneme) # Generate character-level feedback feedback_html = create_character_level_feedback_v2( word_clean, expected_norm, detected_norm, mapping ) # Preserve original punctuation if present if word_original != word_clean: # Find trailing punctuation punct = '' for i in range(len(word_original) - 1, -1, -1): if word_original[i] in string.punctuation: punct = word_original[i] + punct else: break # Find leading punctuation lead_punct = '' for char in word_original: if char in string.punctuation: lead_punct += char else: break display_text = lead_punct + feedback_html + punct else: display_text = feedback_html # For tooltip, use the cleaned word tooltip_text = word_clean else: # Good pronunciation - show original word display_text = word_original tooltip_text = word_original # Create final colored HTML with embedded data colored_html = f'{display_text}' return display_text, colored_html def trim_audio_segment_by_phoneme_position(audio_segment: torch.Tensor, detected_phoneme_full: str, best_start: int, best_end: int, word: str) -> torch.Tensor: """ Trim audio segment based on the position of best matching phoneme substring. Uses 85% of calculated trim percentages to be less aggressive. Ensures final segment is never shorter than 0.1 seconds. Returns the original segment if no trimming is needed. """ detected_norm = normalize_phoneme_string(detected_phoneme_full) total_phoneme_len = len(detected_norm) if total_phoneme_len == 0 or (best_start == 0 and best_end == total_phoneme_len): log(f"🎵 No audio trimming needed for '{word}' (using original segment)") return None # Signal to use original WhisperX timing instead of expanded # Calculate initial trim percentages start_trim_pct = best_start / total_phoneme_len end_trim_pct = (total_phoneme_len - best_end) / total_phoneme_len # Apply 85% factor to be less aggressive start_trim_pct_adjusted = start_trim_pct * 0.85 end_trim_pct_adjusted = end_trim_pct * 0.85 # Calculate samples and duration total_samples = audio_segment.shape[-1] sample_rate = 16000 # Known sample rate original_duration = total_samples / sample_rate # Calculate initial trim amounts start_trim_samples = int(total_samples * start_trim_pct_adjusted) end_trim_samples = int(total_samples * end_trim_pct_adjusted) # Calculate resulting duration trimmed_samples = total_samples - start_trim_samples - end_trim_samples trimmed_duration = trimmed_samples / sample_rate log(f"🎵 Audio trimming for '{word}':") log(f" Original duration: {original_duration:.3f}s ({total_samples} samples)") log(f" Phoneme position: {best_start}-{best_end-1} of {total_phoneme_len} chars") log(f" Initial trim: start={start_trim_pct_adjusted:.1%} ({start_trim_samples} samples), end={end_trim_pct_adjusted:.1%} ({end_trim_samples} samples)") log(f" Resulting duration: {trimmed_duration:.3f}s") # MINIMUM DURATION CHECK: Ensure result is at least 0.1 seconds min_duration = 0.1 min_samples = int(min_duration * sample_rate) if trimmed_samples < min_samples: log(f" ⚠️ Trimmed duration ({trimmed_duration:.3f}s) below minimum ({min_duration}s)") # Calculate how much we need to preserve samples_to_preserve = min_samples total_trim_needed = total_samples - samples_to_preserve if total_trim_needed <= 0: log(f" ⚠️ Original segment already at minimum length, no trimming") return None # Use original WhisperX timing # Redistribute the trimming proportionally while respecting minimum duration original_total_trim = start_trim_samples + end_trim_samples if original_total_trim > 0: # Scale down both trims proportionally scale_factor = total_trim_needed / original_total_trim start_trim_samples = int(start_trim_samples * scale_factor) end_trim_samples = int(end_trim_samples * scale_factor) # Ensure we don't exceed total available trim if start_trim_samples + end_trim_samples > total_trim_needed: excess = (start_trim_samples + end_trim_samples) - total_trim_needed # Remove excess from the larger trim if start_trim_samples > end_trim_samples: start_trim_samples -= excess else: end_trim_samples -= excess log(f" 🔧 Adjusted trim: start={start_trim_samples} samples, end={end_trim_samples} samples") log(f" 🔧 Scale factor applied: {scale_factor:.3f}") else: # Shouldn't happen, but safety check start_trim_samples = 0 end_trim_samples = 0 # Apply final trimming trimmed_start = start_trim_samples trimmed_end = total_samples - end_trim_samples if trimmed_end <= trimmed_start: log(f" ⚠️ Invalid trim range after adjustment, using original segment") return None # Signal to use original WhisperX timing trimmed_segment = audio_segment[:, trimmed_start:trimmed_end] final_duration = trimmed_segment.shape[-1] / sample_rate log(f" ✅ Final result: {trimmed_segment.shape[-1]} samples ({final_duration:.3f}s)") log(f" ✅ Trimmed: {start_trim_samples} from start, {end_trim_samples} from end") return trimmed_segment def get_expected_phonemes(words: List[str]) -> List[str]: """Get expected phonemes using espeak phonemizer""" cache_key = tuple(words) if cache_key in phoneme_cache: log(f"📚 Using cached phonemes for: {words}") cached_result = phoneme_cache[cache_key] log(f" Cached phonemes: {list(zip(words, cached_result))}") return cached_result log(f"🔤 Getting expected phonemes using phonemizer for: {words}") try: # Use espeak phonemizer to get IPA phonemes phonemes = phonemize(words, language='en-us', backend='espeak', strip=True) # Cache the results phoneme_cache[cache_key] = phonemes # Log the phoneme results log(f"✅ Phonemizer results:") for word, phoneme in zip(words, phonemes): log(f" '{word}' → '{phoneme}'") return phonemes except Exception as e: log(f"❌ Error in phonemizer: {e}") log(f" Returning empty phonemes for all words") # Return empty strings as fallback empty_results = [""] * len(words) phoneme_cache[cache_key] = empty_results return empty_results async def generate_tts_audio(word: str) -> str: """Generate TTS audio for a word with silence padding""" if word in tts_cache: return tts_cache[word] try: communicate = edge_tts.Communicate(word, TTS_VOICE) audio_data = b"" async for chunk in communicate.stream(): if chunk["type"] == "audio": audio_data += chunk["data"] if audio_data: # Add silence padding to TTS audio as well # First decode the MP3 to get raw audio import tempfile with tempfile.NamedTemporaryFile(suffix='.mp3', delete=False) as tmp_mp3: tmp_mp3.write(audio_data) tmp_mp3_path = tmp_mp3.name try: # Load the TTS audio tts_waveform, tts_sample_rate = torchaudio.load(tmp_mp3_path) # Resample if needed to match our standard rate if tts_sample_rate != 16000: tts_waveform = torchaudio.transforms.Resample(tts_sample_rate, 16000)(tts_waveform) tts_sample_rate = 16000 # Add 0.25s silence padding on each end padding_samples = int(0.25 * tts_sample_rate) silence_shape = list(tts_waveform.shape) silence_shape[-1] = padding_samples silence_padding = torch.zeros(silence_shape) # Concatenate: silence + audio + silence padded_waveform = torch.cat([silence_padding, tts_waveform, silence_padding], dim=-1) # Convert back to base64 buffer = io.BytesIO() torchaudio.save(buffer, padded_waveform, tts_sample_rate, format="wav") buffer.seek(0) audio_b64 = base64.b64encode(buffer.read()).decode('utf-8') tts_cache[word] = audio_b64 log(f"🔇 TTS for '{word}': Added 0.25s silence padding on each end") return audio_b64 finally: # Clean up temp file if os.path.exists(tmp_mp3_path): os.remove(tmp_mp3_path) except Exception as e: log(f"TTS failed for '{word}': {e}") return "" def audio_to_base64(audio_segment: torch.Tensor, sample_rate: int, add_padding: bool = True) -> str: """ Convert audio tensor to base64 string. Args: audio_segment: The audio tensor to convert sample_rate: Sample rate of the audio add_padding: If True, adds 0.25s of silence on each end to prevent audio processor lag Returns: Base64 encoded audio string """ try: if add_padding: # Add 0.25 seconds of silence on each end padding_samples = int(0.25 * sample_rate) # 0.25 seconds worth of samples # Create silence padding (zeros with same shape as audio segment) silence_shape = list(audio_segment.shape) silence_shape[-1] = padding_samples silence_padding = torch.zeros(silence_shape) # Concatenate: silence + audio + silence padded_segment = torch.cat([silence_padding, audio_segment, silence_padding], dim=-1) log(f"🔇 Added silence padding: {padding_samples} samples (0.25s) on each end") log(f" Original: {audio_segment.shape[-1]} samples → Padded: {padded_segment.shape[-1]} samples") audio_segment = padded_segment buffer = io.BytesIO() torchaudio.save(buffer, audio_segment, sample_rate, format="wav") buffer.seek(0) return base64.b64encode(buffer.read()).decode('utf-8') except Exception as e: log(f"Audio conversion failed: {e}") return "" @app.post("/api/transcribe") async def transcribe(audio: UploadFile = File(...), similarity_threshold: float = Form(0.4)): log("=== STARTING WHISPERX ENGLISH-ONLY PHONEME ANALYSIS ===") # Use similarity threshold from frontend (default 0.4) similarity = max(0.0, min(1.0, similarity_threshold)) # Clamp between 0 and 1 log(f"Using similarity threshold: {similarity:.2f}") try: # Load WhisperX models if needed load_whisperx_models() # 1. Convert and load audio data = await audio.read() wav_io = convert_webm_to_wav(data) # Save to temporary file for WhisperX temp_audio_path = "/tmp/temp_audio.wav" with open(temp_audio_path, "wb") as f: f.write(wav_io.getvalue()) # Load audio with WhisperX audio_data = whisperx.load_audio(temp_audio_path) log(f"Audio loaded for WhisperX: {len(audio_data)} samples") # 2. Get transcription with WhisperX - EXPLICITLY SET TO ENGLISH result = whisperx_model.transcribe(audio_data, batch_size=16, language="en") # 3. Get precise word alignments with WhisperX (if alignment model available) if whisperx_align_model is not None: aligned_result = whisperx.align(result["segments"], whisperx_align_model, whisperx_metadata, audio_data, device="cpu") else: log("WARNING: Alignment model not available, using basic word splitting") # Fallback: split text into words with approximate timing aligned_result = {"segments": []} for segment in result["segments"]: text = segment.get("text", "").strip() if not text: continue words = text.split() duration = segment["end"] - segment["start"] time_per_word = duration / len(words) if words else 0 word_list = [] for i, word in enumerate(words): word_start = segment["start"] + (i * time_per_word) word_end = segment["start"] + ((i + 1) * time_per_word) word_list.append({ "word": word, "start": word_start, "end": word_end, "score": 0.9 # Default confidence }) aligned_result["segments"].append({ "text": text, "start": segment["start"], "end": segment["end"], "words": word_list }) # Extract word-level data from WhisperX results words = [] word_texts = [] # Original with punctuation for display word_texts_clean = [] # Cleaned for phoneme processing word_timings = [] for segment in aligned_result["segments"]: if "words" in segment: for word_info in segment["words"]: if "start" in word_info and "end" in word_info and word_info["word"]: original_word = word_info["word"].strip() # Convert digits to words for better phoneme analysis word_converted = convert_digits_to_words(original_word) cleaned_word = clean_word_for_phonemes(word_converted) # Only process words that have alphabetical content after cleaning if cleaned_word: words.append(word_info) word_texts.append(word_converted) # Use converted form for display word_texts_clean.append(cleaned_word) # Clean for processing word_timings.append((word_info["start"], word_info["end"])) if not words: return {"resolved": "", "resolved_colored": "", "audio_data": []} log(f"Found {len(words)} words with precise WhisperX timings") # Log WhisperX timings log("=== WHISPERX PRECISE TIMINGS ===") for i, (word_original, word_clean, (start, end)) in enumerate(zip(word_texts, word_texts_clean, word_timings)): gap = "" if i > 0: prev_end = word_timings[i-1][1] gap_duration = start - prev_end gap = f" | gap: {gap_duration:.3f}s" log(f"Word {i}: '{word_original}' (clean: '{word_clean}') at {start:.3f}s-{end:.3f}s{gap}") # 4. Get expected phonemes using CLEANED words expected_phonemes = get_expected_phonemes(word_texts_clean) # 5. Load audio as tensor for phoneme analysis waveform, sample_rate = torchaudio.load(temp_audio_path) if sample_rate != 16000: waveform = torchaudio.transforms.Resample(sample_rate, 16000)(waveform) sample_rate = 16000 # 6. Process each word using expanded timing with sliding window matching results = [] audio_data_list = [] # Generate TTS for all words concurrently (using CLEANED words) log("Generating TTS audio...") tts_tasks = [generate_tts_audio(word_clean) for word_clean in word_texts_clean] tts_results = await asyncio.gather(*tts_tasks) log("\n=== PROCESSING WORDS WITH EXPANDED TIMING + SLIDING WINDOW ===") for i, (word_info, word_original, word_clean, (start_time, end_time)) in enumerate(zip(words, word_texts, word_texts_clean, word_timings)): expected_phoneme = expected_phonemes[i] if i < len(expected_phonemes) else "" log(f"\n--- Processing word {i}: '{word_original}' (clean: '{word_clean}') ---") log(f"🔊 WhisperX timing: {start_time:.3f}s - {end_time:.3f}s (duration: {end_time - start_time:.3f}s)") log(f"🎯 Expected phoneme: '{expected_phoneme}'") # DEBUGGING: Special attention to problematic words if word_clean.lower() in ['go', 'no', 'so', 'to', 'do'] or len(expected_phoneme) > len(word_clean): log(f"⚠️ SPECIAL CASE: Word '{word_clean}' has {len(word_clean)} letters but {len(expected_phoneme)} phonemes") log(f" This may be a diphthong case requiring special handling") # For very short words, expand the WhisperX timing itself before processing original_duration = end_time - start_time if original_duration < 0.1: log(f"🔍 Ultra-short word detected ({original_duration:.3f}s), expanding WhisperX timing") audio_duration = waveform.shape[-1] / sample_rate # Expand WhisperX boundaries by ±0.05s start_time = max(0, start_time - 0.05) end_time = min(audio_duration, end_time + 0.05) log(f" Expanded WhisperX timing: {start_time:.3f}s - {end_time:.3f}s (new duration: {end_time - start_time:.3f}s)") # Show gaps between words if i > 0: prev_end = word_timings[i-1][1] gap = start_time - prev_end if gap > 0: log(f"⏸️ Gap from previous word: {gap:.3f}s") elif gap < 0: log(f"⚠️ OVERLAP with previous word: {gap:.3f}s") else: log(f"🔗 No gap (continuous)") # Calculate expanded timing (±0.125s with boundary protection) expansion_seconds = 0.125 audio_duration = waveform.shape[-1] / sample_rate expanded_start = max(0, start_time - expansion_seconds) expanded_end = min(audio_duration, end_time + expansion_seconds) log(f"🔍 Timing expansion: {start_time:.3f}s-{end_time:.3f}s → {expanded_start:.3f}s-{expanded_end:.3f}s") # Extract expanded audio segment expanded_audio_segment = extract_audio_segment(waveform, sample_rate, expanded_start, expanded_end, word_clean, verbose=True) # Check for word boundary overlap and trim if needed log(f"🔍 Checking word boundary overlap for '{word_clean}'...") boundary_offset = detect_word_boundary_overlap(expanded_audio_segment, sample_rate, word_clean) if boundary_offset > 0: log(f"🔧 Detected word overlap, trimming {boundary_offset:.3f}s from start") trim_samples = int(boundary_offset * sample_rate) expanded_audio_segment = expanded_audio_segment[:, trim_samples:] # Update expanded_start for accurate timing logs expanded_start += boundary_offset log(f" Updated expanded start: {expanded_start:.3f}s") # ALSO apply the boundary offset to WhisperX timing original_start_time = start_time start_time = max(0, start_time + boundary_offset) end_time = max(start_time + 0.01, end_time) # Ensure minimum 10ms duration log(f" Updated WhisperX timing: {original_start_time:.3f}s → {start_time:.3f}s (shifted +{boundary_offset:.3f}s)") # Also extract WhisperX original timing for comparison (now using updated start_time) whisperx_audio_segment = extract_audio_segment(waveform, sample_rate, start_time, end_time, word_clean, verbose=False) # Detect phoneme from expanded audio segment detected_phoneme_raw = detect_phoneme_from_audio(expanded_audio_segment, sample_rate, word_clean) # Get expected phoneme and normalize both detected_phoneme_norm = normalize_phoneme_string(detected_phoneme_raw) expected_phoneme_norm = normalize_phoneme_string(expected_phoneme) log(f"🔊 Raw detected phoneme (expanded): '{detected_phoneme_raw}'") log(f"🧹 Normalized detected: '{detected_phoneme_norm}'") log(f"🧹 Normalized expected: '{expected_phoneme_norm}'") # Find best matching substring using sliding window best_match_phoneme, similarity_score, match_start, match_end = sliding_window_phoneme_match( detected_phoneme_raw, expected_phoneme, word_clean ) log(f"🔊 Final similarity score: {similarity_score:.3f}") # Trim audio segment based on best phoneme match position trimmed_audio_segment = trim_audio_segment_by_phoneme_position( expanded_audio_segment, detected_phoneme_raw, match_start, match_end, word_clean ) # Use original WhisperX timing if no trimming was needed, otherwise use trimmed if trimmed_audio_segment is None: final_audio_segment = whisperx_audio_segment log(f"🎵 Using original WhisperX timing (no trimming needed)") log(f" Final segment: WhisperX original ({whisperx_audio_segment.shape[-1]} samples, {whisperx_audio_segment.shape[-1]/sample_rate:.3f}s)") log(f" Segment timing: {start_time:.3f}s - {end_time:.3f}s") else: final_audio_segment = trimmed_audio_segment log(f"🎵 Using trimmed segment from expanded timing") log(f" Final segment: Processed ({trimmed_audio_segment.shape[-1]} samples, {trimmed_audio_segment.shape[-1]/sample_rate:.3f}s)") # Calculate the actual timing of the processed segment final_duration = trimmed_audio_segment.shape[-1] / sample_rate expanded_duration = expanded_end - expanded_start # Calculate trim amounts based on phoneme positions detected_phoneme_norm = normalize_phoneme_string(detected_phoneme_raw) total_phoneme_len = len(detected_phoneme_norm) if total_phoneme_len > 0: start_trim_pct = match_start / total_phoneme_len * 0.85 # Apply 85% factor end_trim_pct = (total_phoneme_len - match_end) / total_phoneme_len * 0.85 time_trimmed_from_start = expanded_duration * start_trim_pct time_trimmed_from_end = expanded_duration * end_trim_pct final_start_time = expanded_start + time_trimmed_from_start final_end_time = expanded_end - time_trimmed_from_end log(f" Segment timing: {final_start_time:.3f}s - {final_end_time:.3f}s") else: log(f" Segment timing: {expanded_start:.3f}s - {expanded_end:.3f}s (no phoneme-based calculation)") log(f"🔊 Audio segments returned to user:") log(f" 1️⃣ Expected (TTS): Generated speech") log(f" 2️⃣ User audio: {'WhisperX original' if trimmed_audio_segment is None else 'Processed/trimmed'} ({final_audio_segment.shape[-1]} samples)") log(f" 3️⃣ WhisperX raw: Original timing ({whisperx_audio_segment.shape[-1]} samples)") if trimmed_audio_segment is not None and final_audio_segment.shape[-1] != whisperx_audio_segment.shape[-1]: sample_diff = final_audio_segment.shape[-1] - whisperx_audio_segment.shape[-1] time_diff = sample_diff / sample_rate log(f" 📊 Segment difference: {sample_diff:+d} samples ({time_diff:+.3f}s) processed vs WhisperX") log(f"🔊 Final similarity score: {similarity_score:.3f}") log(f"🎨 Final audio segment samples: {final_audio_segment.shape[-1]} (duration: {final_audio_segment.shape[-1]/sample_rate:.3f}s)") log(f"🎤 WhisperX original segment samples: {whisperx_audio_segment.shape[-1]} (duration: {whisperx_audio_segment.shape[-1]/sample_rate:.3f}s)") log(f"⏰ Timing comparison:") log(f" WhisperX original: {start_time:.3f}s - {end_time:.3f}s (duration: {end_time - start_time:.3f}s)") log(f" Expanded timing: {expanded_start:.3f}s - {expanded_end:.3f}s (duration: {expanded_end - expanded_start:.3f}s)") # Store results - now with both original and clean versions results.append({ 'word_original': word_original, # Original with punctuation for display 'word_clean': word_clean, # Cleaned version for phoneme processing 'detected_phoneme': best_match_phoneme, # Use best matching substring 'expected_phoneme': expected_phoneme, 'similarity_score': float(similarity_score), 'start_time': float(start_time), 'end_time': float(end_time), 'whisperx_confidence': float(word_info.get('score', 1.0)) }) # Prepare audio data with all three segments (use ORIGINAL word for display) # All three audio segments will have 0.25s silence padding added automatically user_audio_b64 = audio_to_base64(final_audio_segment, sample_rate) # Padded whisperx_audio_b64 = audio_to_base64(whisperx_audio_segment, sample_rate) # Padded expected_audio_b64 = tts_results[i] # Already padded in generate_tts_audio audio_data_list.append({ "word": word_original, # Original with punctuation for display "expected_audio": expected_audio_b64, # TTS with padding "user_audio": user_audio_b64, # User's pronunciation with padding "whisperx_audio": whisperx_audio_b64, # WhisperX original with padding "start_time": float(start_time), "end_time": float(end_time), "similarity_score": float(similarity_score), "detected_phoneme": best_match_phoneme, # Use best matching substring "expected_phoneme": expected_phoneme, "whisperx_confidence": float(word_info.get('score', 1.0)) }) # 7. Format output using the refactored v2 functions resolved_output = [] resolved_colored = [] for result in results: output_text, colored_text = format_output_word_v2( result['word_original'], # Pass both versions result['word_clean'], result['similarity_score'], result['detected_phoneme'], result['expected_phoneme'], similarity ) resolved_output.append(output_text) resolved_colored.append(colored_text) # Clean up temporary file os.remove(temp_audio_path) log("=== WHISPERX ENGLISH-ONLY PHONEME ANALYSIS COMPLETE ===") return { "resolved": " ".join(resolved_output), "resolved_colored": " ".join(resolved_colored), "audio_data": audio_data_list, "debug_info": { "total_words": len(words), "similarity_threshold": similarity, "alignment_method": "WhisperX English-only + Sliding Window", "results_summary": [ { "word": r['word_original'], "score": float(r['similarity_score']), "detected": r['detected_phoneme'], "expected": r['expected_phoneme'], "whisperx_confidence": r['whisperx_confidence'] } for r in results ] } } except Exception as e: log(f"ERROR in transcribe: {str(e)}") import traceback log(f"Traceback: {traceback.format_exc()}") return { "resolved": "Error occurred", "resolved_colored": "Error occurred", "audio_data": [], "debug_info": {"error": str(e)} } @app.get("/") def root(): return "Clean Fonetik with WhisperX English-only + Character-Level Feedback running" @app.post("/api/clear-cache") def clear_cache(): global phoneme_cache, tts_cache phoneme_cache.clear() tts_cache.clear() return {"message": "Cache cleared"}