The A/B crossfader. Two video inlets - inlet 1 is A, inlet 2 is B - and one outlet carrying the dissolve: Fade at 0 shows A, at 1 shows B, anywhere between a mix whose law Curve sets.
Fade is an ordinary param, which is the whole trick: map a MIDI controller to it and you have a hardware video crossfader; put an LFO modulation route on it (synced, 16 beats) and the two feeds trade places on a musical cycle; draw it in an automation lane and the cut list is part of the song.
Chain them for more buses (A/B into C/D), or crossfade two whole Lumen composites for scene-to-scene transitions before the VideoOut.
Parameters
| Fade | the dissolve. 0 is all A (inlet 1), 1 is all B (inlet 2), anywhere between is a mix shaped by Curve. |
| Curve | the law of the dissolve, the same knob as on the audio Crossfader. At 0 the mix is linear, so halfway through both pictures sit at half brightness and the frame looks dim. Turn it up and each side holds its brightness further across the fade: two thirds is the equal-power law, where halfway shows both pictures near full and bright areas may clip; 1 is the hard version. |