Colour of a cell/pixel is determined by the fitting error, or the amount of mis-match, found when the coordinates are tried in the formula for the Cassinian ovals.
The colours were 24-bit when put in the bitmaps, which were then reduced to a 256-colour .gif format by the great Xat.com Image Optimizer. (Recommended).

Before applying (deciding on) a colour, the amount of mismatch was multiplied by a number varying from 0.2 to 500. That's how the 27 'movie frames' were made.

List of movieframes and applied multiplication factor: