diff options
Diffstat (limited to 'app/stt.py')
| -rw-r--r-- | app/stt.py | 128 |
1 files changed, 101 insertions, 27 deletions
@@ -6,10 +6,10 @@ import os import pyaudio from pydub import AudioSegment from shared_thread_data import SharedThreadData +from silero_vad import load_silero_vad, get_speech_timestamps import sys import time import typing -import vad import wave @@ -33,7 +33,7 @@ class AudioStream(): class MicStream(AudioStream): CHUNK_SZ = 1024 - def __init__(self, which_mic: str): + def __init__(self, cfg: typing.Dict): self.p = pyaudio.PyAudio() self.stream = None self.sample_rate = None @@ -45,8 +45,11 @@ class MicStream(AudioStream): # If set, incoming frames are simply discarded. self.paused = False - print(f"Finding mic {which_mic}", file=sys.stderr) - self.dumpMicDevices() + which_mic = cfg["microphone"] + + if cfg["enable_debug_mode"]: + print(f"Finding mic {which_mic}", file=sys.stderr) + self.dumpMicDevices() got_match = False device_index = -1 @@ -59,8 +62,9 @@ class MicStream(AudioStream): elif which_mic == "beyond": target_str = "Microphone (Beyond)" else: - print(f"Mic {which_mic} requested, treating it as a numerical " + - "device ID", file=sys.stderr) + if cfg["enable_debug_mode"]: + print(f"Mic {which_mic} requested, treating it as a numerical " + + "device ID", file=sys.stderr) device_index = int(which_mic) got_match = True if not got_match: @@ -79,9 +83,11 @@ class MicStream(AudioStream): raise KeyError(f"Mic {which_mic} not found") info = self.p.get_device_info_by_host_api_device_index(0, device_index) - print(f"Found mic {which_mic}: {info['name']}", file=sys.stderr) + if cfg["enable_debug_mode"]: + print(f"Found mic {which_mic}: {info['name']}", file=sys.stderr) self.sample_rate = int(info['defaultSampleRate']) - print(f"Mic sample rate: {self.sample_rate}", file=sys.stderr) + if cfg["enable_debug_mode"]: + print(f"Mic sample rate: {self.sample_rate}", file=sys.stderr) self.stream = self.p.open( rate=self.sample_rate, @@ -289,19 +295,40 @@ class AudioSegmenter: def __init__(self, min_silence_ms=250, max_speech_s=5): - self.vad_options = vad.VadOptions( - min_silence_duration_ms=min_silence_ms, - max_speech_duration_s=max_speech_s) - pass + self.min_silence_ms = min_silence_ms + self.max_speech_s = max_speech_s + + # Load Silero VAD model + self.model = load_silero_vad() + + self.vad_threshold = 0.3 + self.min_silence_duration_ms = min_silence_ms + self.max_speech_duration_s = max_speech_s + + self.speech_pad_ms = 300 def segmentAudio(self, audio: bytes): - audio = np.frombuffer(audio, + # Convert audio bytes to numpy array expected by silero-vad + audio_array = np.frombuffer(audio, dtype=np.int16).flatten().astype(np.float32) / 32768.0 - return vad.get_speech_timestamps(audio, vad_options=self.vad_options) + + # Get speech timestamps using silero-vad + # Note: silero-vad expects sample rate of 16000 Hz which matches AudioStream.FPS + speech_timestamps = get_speech_timestamps( + audio_array, + self.model, + sampling_rate=AudioStream.FPS, + threshold=self.vad_threshold, + min_silence_duration_ms=self.min_silence_duration_ms, + max_speech_duration_s=self.max_speech_duration_s, + return_seconds=False # We want frame indices, not seconds + ) + + return speech_timestamps # Returns the stable cutoff (if any) and whether there are any segments. def getStableCutoff(self, audio: bytes) -> typing.Tuple[int, bool]: - min_delta_frames = int((self.vad_options.min_silence_duration_ms * + min_delta_frames = int((self.min_silence_duration_ms * AudioStream.FPS) / 1000.0) cutoff = None @@ -379,8 +406,9 @@ class Whisper: model_str = cfg["model"] model_root = os.path.join(parent_dir, "Models", os.path.normpath(model_str)) - print(f"Model {cfg['model']} will be saved to {model_root}", - file=sys.stderr) + if cfg["enable_debug_mode"]: + print(f"Model {cfg['model']} will be saved to {model_root}", + file=sys.stderr) model_device = "cuda" if cfg["use_cpu"]: @@ -395,21 +423,42 @@ class Whisper: download_root = model_root, local_files_only = already_downloaded) + self.context_window_chars = 200 # Keep last 200 chars of context + self.recent_context = "" # Store recent committed text + + def update_context(self, committed_text: str): + """Update the context with recently committed text.""" + self.recent_context = (self.recent_context + " " + committed_text).strip() + # Keep only the last N characters to avoid prompt getting too long + if len(self.recent_context) > self.context_window_chars: + self.recent_context = self.recent_context[-self.context_window_chars:] + def transcribe(self, frames: bytes = None) -> typing.List[Segment]: if frames is None: frames = self.collector.getAudio() - # Convert from signed 16-bit int [-32768, 32767] to signed 32-bit float on - # [-1, 1]. + + # Convert audio to float32 audio = np.frombuffer(frames, dtype=np.int16).flatten().astype(np.float32) / 32768.0 + # Build context-aware prompt + prompt = self._build_prompt() + t0 = time.time() segments, info = self.model.transcribe( audio, language = langcodes.find(self.cfg["language"]).language, vad_filter = True, temperature=0.0, - without_timestamps = False) + without_timestamps = False, + initial_prompt=prompt, + beam_size=5, + best_of=5, + condition_on_previous_text=True, + compression_ratio_threshold=2.4, + log_prob_threshold=-1.0, + no_speech_threshold=0.6 + ) res = [] for s in segments: # Manual touchup. I see a decent number of hallucinations sneaking @@ -445,6 +494,17 @@ class Whisper: print(f"Transcription latency (s): {t1 - t0}") return res + def _build_prompt(self) -> str: + """Build a context-aware prompt for Whisper.""" + user_prompt = self.cfg["user_prompt"] + context_prompt = "" + if self.recent_context and len(self.recent_context) > 0: + context_prompt = f"Here is the context so far: {self.recent_context}" + + prompts = [user_prompt, context_prompt] + prompts = [p for p in prompts if p and len(p) > 0] + return " ".join(prompts) + class TranscriptCommit: def __init__(self, delta: str, @@ -502,10 +562,21 @@ class VadCommitter: latency_s = self.collector.now() - self.collector.begin() duration_s = stable_cutoff / AudioStream.FPS start_ts = self.collector.begin() - commit_audio = self.collector.dropAudioPrefixByFrames(stable_cutoff) + + # Get the filtered audio first, then extract the portion we need + filtered_audio = self.collector.getAudio() + commit_audio = filtered_audio[:stable_cutoff * AudioStream.FRAME_SZ] + + # Now drop the prefix from the collector + self.collector.dropAudioPrefixByFrames(stable_cutoff) segments = self.whisper.transcribe(commit_audio) delta = ''.join(s.transcript for s in segments) + + # Update whisper's context with the committed text + if delta.strip(): + self.whisper.update_context(delta.strip()) + audio = self.collector.getAudio() if self.cfg["enable_debug_mode"]: for s in segments: @@ -540,11 +611,11 @@ class VadCommitter: def transcriptionThread(shared_data: SharedThreadData): last_stable_commit = None - stream = MicStream(shared_data.cfg["microphone"]) + stream = MicStream(shared_data.cfg) collector = AudioCollector(stream) collector = CompressingAudioCollector(collector) + collector = BoostingAudioCollector(collector, -12.0, shared_data.cfg) collector = NormalizingAudioCollector(collector) - collector = BoostingAudioCollector(collector, 0.0, shared_data.cfg) whisper = Whisper(collector, shared_data.cfg) segmenter = AudioSegmenter(min_silence_ms=shared_data.cfg["min_silence_duration_ms"], max_speech_s=shared_data.cfg["max_speech_duration_s"]) @@ -553,6 +624,8 @@ def transcriptionThread(shared_data: SharedThreadData): transcript = "" preview = "" + print(f"Ready to go!", flush=True) + while not shared_data.exit_event.is_set(): time.sleep(shared_data.cfg["transcription_loop_delay_ms"] / 1000.0); @@ -561,8 +634,7 @@ def transcriptionThread(shared_data: SharedThreadData): commit = committer.getDelta() if len(commit.delta) > 0 or len(commit.preview) > 0: - # Avoid re-sending text after long pauses. User controls the length - # of the pause in the UI. + # Avoid re-sending text after long pauses if shared_data.cfg["reset_after_silence_s"] > 0: silence_duration = 0 if last_stable_commit: @@ -571,10 +643,12 @@ def transcriptionThread(shared_data: SharedThreadData): last_stable_commit.duration_s silence_duration = commit.start_ts - last_commit_end_ts if silence_duration > shared_data.cfg["reset_after_silence_s"]: - print(f"Resetting transcript after {silence_duration}-second " - "silence", file=sys.stderr) + if shared_data.cfg["enable_debug_mode"]: + print(f"Resetting transcript after {silence_duration}-second " + "silence", file=sys.stderr) transcript = "" preview = "" + whisper.recent_context = "" # Reset context too if commit.delta: last_stable_commit = commit |