2011

Table Of Contents
Original image
The Flares parameters let you add lines and streaks emanating from bright
lights and reflections. You can set the intensity of the flares, as well as the
number of flares. An intensity of 0 (the default) will disable flare generation.
The rotation of the lines can be animated to simulate flares that seem to rotate
as the camera moves relative to the light sources. The Randomness parameter
controls how evenly distributed the lines are. A value of 0 makes the flare
lines uniformly distributed around a circle, while a value of 1 makes them
completely randomly distributed. You can also set a seed value to choose a
particular sequence of lines. The effect of adding flares will be somewhat like
the linear patterns in the right image below.
Original image
The halo is a ring of brightness of a specified radius from the center of bright
lights, and with a specified width. If the radii differ among the color channels,
the effect is a rainbow halo like in the following right image. This is controlled
by the Aberration parameter. There is also an intensity parameter to adjust
the strength of the halo; the default value of 0 disables the halo creation.
The Grating is a set of lines of random intensity, uniformly distributed around
the circle. Increasing the Grating Density parameter increases the number of
lines, and the smoother it appears.
404 | Chapter 17 Image Processing Tools