Collect and label audio
Record many examples of the target wake word and negative background audio across speakers, devices and environments, then label precise activation windows.
Detect a wake word event. Balance false accepts and rejects.
Wake-word detection locates brief trigger phrases in continuous audio and must balance false accepts (activations without the wake word) against missed activations. Real data collection, augmentation, and low-latency feature extraction are central; noise, overlapping speech and microphone variability are common failure modes.
Learning concept · Not a validated service
Wake-word detection locates brief trigger phrases in continuous audio and must balance false accepts (activations without the wake word) against missed activations. Real data collection, augmentation, and low-latency feature extraction are central; noise, overlapping speech and microphone variability are common failure modes.
A proposed extension: run an on-device wake-word detector that only suggests activation to a human operator in noisy environments. For any security or voice-control application, keep a human or safe fallback in the loop; the starter code does not deliver a production-ready model.
Record many examples of the target wake word and negative background audio across speakers, devices and environments, then label precise activation windows.
Compute short-time spectral features (MFCCs, log-mel spectrograms) per frame and aggregate with sliding windows for low-latency detection.
Train a compact classifier or small CNN on frame/window features; validate with per-window precision, recall and ROC curves.
Measure false accept rate (FAR), false reject rate (FRR), latency and CPU/memory usage on target hardware.
The supplied starter synthesises pure-tone 1-second clips at two different centre frequencies, computes simple FFT-derived summary features (mean, std, argmax, 95th percentile), then trains a RandomForestClassifier and prints a classification report. It does not use speech, wake words, or real acoustic recordings.
def synth_clip(freq, label):
t = np.linspace(0, 1, sample_rate, endpoint=False)
signal = np.sin(2 * np.pi * freq * t) + 0.05 * rng.normal(size=sample_rate)
spectrum = np.abs(np.fft.rfft(signal))
features = [
spectrum.mean(),
spectrum.std(),The starter uses synthetic sine tones with additive Gaussian noise and four crude FFT statistics; these do not represent speech or wake-word variability, so reported performance does not validate wake-word detection. The feature extraction and dataset size are far too small for a realistic wake-word system and do not measure latency or per-frame detection metrics.
A proposed extension: replace the synthetic clips with a small collected dataset of spoken wake-word examples and diverse background clips, extract mel-filterbank features with frame-level labels, and train a small streaming model that outputs per-frame detection scores for real-time evaluation.
This is a potential application pathway, not a delivered product. The supplied starter does not implement this service or validate it with real users.
Networkers Home runs this topic inside its AI Engineer Course, with placement support and hands-on labs.