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Rumbler

The Rumbler plugin can be used to create dream-like or earthquake-like noise in the video. It creates noise by jiggling the corners through use of perspective transformation at the corners. The algorithm used is:

Rumbler (value) = (value at time) + amplitude×(random generator)

The random generator varies from -0.5 to 0.5. The rumble perturbs the normal values at time points which occur rate times a second. The values used between the rumble points are interpolated, so that the value jiggles rate times a second, by as much as the rumble amplitude. The time unit is frames per second. The corners are in units of percent width/height (figure 10.62).

Figure 10.62: Rumbler control window

Screencast shows:

Time jittering - 20 fps 1 time a second. Corners jittering - 25% 5 times a second. Using random seed 0 for a rumble sequence.

Plugin variables:

Rumbler:
  gain applied to random rumbler.
Rate:
  number of times per second.
Time:
  number of frames per rate times a second; if 0 has no effect on results.
Space:
  corners jiggling in percentage per rate times a second; if 0 has no effect on results.
Seq:
  is a random seed number; any reasonable positive or negative number you choose.