Speaker Diarization: How AI Knows Who Said What in Your Meeting

Speaker diarization is the process of segmenting a transcript by who was speaking — turning 'we should delay the launch and I'll tell the client' into a record where the first clause belongs to the engineering lead and the commitment belongs, specifically, to Alex. Without diarization, a transcript is searchable but not attributable; with it, action items get owners and decisions get accountable voices.

The two ways diarization happens

• Acoustic diarization: when all voices arrive in one mixed audio stream (a conference room mic, a bot recording), the system clusters speech segments by voice characteristics — pitch, timbre, cadence — and assigns anonymous labels like 'Speaker 1'. It works, but overlapping speech, similar voices, and background noise cause misattributions.
• Channel-based diarization: when the platform captures each participant's audio as a separate stream — which video conferencing architecture naturally provides — attribution is essentially exact. The platform knows which authenticated participant's microphone produced each word, by construction, and labels them by name rather than 'Speaker 2'.

Why this is a platform-architecture advantage

This is the quiet reason native transcription beats notetaker bots on attribution: a bot joins the call as one participant and hears the mixed output — it must reconstruct acoustically what the platform already knows structurally. MeetOye's Oya sits inside the platform, receives per-participant streams, and attributes speech to named participants directly. The visible payoff is in the recap: action items arrive already assigned to the person who committed to them, by name, without a 'Speaker 3' in sight.

Where diarization still gets hard

• Shared devices: two people on one laptop in a huddle room collapse into one channel — the acoustic problem returns for that channel.
• Overlap: even with clean channels, transcribing simultaneous speech accurately remains the field's hardest case.
• Very short interjections: one-word agreements ('yes', 'agreed') are easy to attribute but easy for summarizers to under-weight — worth remembering when a recap says a decision was unopposed.