Collect and prepare audio
Assemble multi-speaker recordings with time-aligned speaker labels; apply voice-activity detection and normalize sample rates.
Separate speakers in audio. Assess segment labels.
Speaker diarization segments an audio recording into time ranges and assigns a speaker label to each segment. Real diarization requires frame-level features (for example MFCCs or embeddings), voice-activity detection, segmentation and clustering or supervised speaker-attribution models. Typical failure cases include overlapping speech, short speaker turns, background noise and domain mismatch between training audio and deployment recordings.
Learning concept · Not a validated service
Speaker diarization segments an audio recording into time ranges and assigns a speaker label to each segment. Real diarization requires frame-level features (for example MFCCs or embeddings), voice-activity detection, segmentation and clustering or supervised speaker-attribution models. Typical failure cases include overlapping speech, short speaker turns, background noise and domain mismatch between training audio and deployment recordings.
A proposed application: help media teams or meeting-software vendors present a speaker-labelled transcript where a human reviewer can correct segment boundaries and speaker identities. This extension is not implemented by the supplied starter code.
Assemble multi-speaker recordings with time-aligned speaker labels; apply voice-activity detection and normalize sample rates.
Compute frame-level features such as MFCCs or speaker embeddings and aggregate or window them to create segment representations.
Start with simple segmentation plus clustering on embeddings or a supervised classifier for short segments and measure diarization error rate (DER).
Report DER, confusion by speaker duration and overlap-handling; inspect short turns and overlapping speech for manual review paths.
The supplied starter synthesises two classes of single-second sine-wave audio clips with additive noise, computes a small FFT-based feature vector (mean, std, argmax, 95th percentile), builds a 160-sample dataset, and trains a RandomForestClassifier to predict the two labels. It prints a classification report on a held-out test split.
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(),
spectrum.argmax(),
np.percentile(spectrum, 95),
]The starter does not implement diarization: it uses one-second synthetic tones (not real speech), extracts simple FFT summary statistics rather than frame-level speech features or embeddings, and trains a classifier on fixed-length clips. There is no segmentation, no speaker-turn detection, no overlap handling and no use of real multi-speaker datasets, so it cannot be used to claim diarization performance.
A proposed extension: replace synthetic clips with real recordings, compute frame-level speaker embeddings (for example with a pretrained speaker‑embedding model), run voice-activity detection, segment audio into short windows, cluster embeddings to assign speaker labels, and present an editor where humans can correct boundaries.
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.