Front-loads the remaining visual adapters per the Signal→Meet→Zoom priority.
All three reuse GridCallAnalyzer's coloured-border (saturated) detection path
and share the new bottom-left name anchor:
- GridCallAnalyzer: generalise nameAtBottom:Bool into a NameAnchor enum
(.bottomCenter for Signal's centered footer, .bottomLeft for Meet/Zoom/Teams
where the name hugs the tile's bottom-left corner, .center for completeness).
tileRect estimates the tile up-and-right of a bottom-left name.
- MeetAdapter (Google-blue ring, browser-hosted), ZoomAdapter (green/yellow
border), TeamsAdapter (violet ring): coloured-border on, white-border off,
bottom-left names. Geometry constants are first-pass pending real fixtures.
- AdapterRegistry.adapter(for:) maps CallDetector.DetectedApp → AppAdapter so
VisualObserver can be constructed when live visual capture is wired in;
unmapped apps degrade to audio-only.
Synthetic 4-tile tests: Meet picks each blue-bordered speaker with no
adjacent-tile bleed, Zoom picks the green-bordered speaker, and Signal's
white-only detector correctly ignores a coloured border. 18/18 XCTest pass.
Signal's active-speaker cue is a 3px #ffffff rounded border (saturation ≈ 0),
which the saturation-based highlight detector could never see. Per the
Signal-Desktop source review:
- FrameSampler.thinWhitePoints: grid-sample near-white pixels that sit on a
THIN structure (a non-white pixel within edgeGap on some axis) so a border/
ring counts but a solid white blob (face, bright video) does not.
- GridCallAnalyzer: combine coloured (saturated) + white (thin) highlight
pixels; exclude name-text regions so the white footer name can't be mistaken
for the border; estimate the tile UP from the name footer (nameAtBottom);
attribute each highlight pixel to exactly one tile by containment (nearest
centre as tiebreak) so a border can't bleed into an adjacent tile.
- SignalAdapter: white border on, coloured off, name-at-bottom geometry.
Synthetic 4-tile harness now isolates each speaker with no adjacent-tile bleed;
all 15 XCTest cases pass. Real-screenshot geometry calibration still pending.
Grant Gilliam