Bloom

IntermediateArtist

The bloom effect takes the brightest areas of an image, extends them, and bleeds them into the surrounding areas to simulate bright light overwhelming the camera.

It uses the result of the bright filter effect as input.

Properties

Property	Description
Radius	Radius of the bloom. Note that high values can affect performance.
Amount	Amount/strength of bloom.
Sigma Ratio	This affects the fall-off of the bloom. It's the standard deviation (sigma) used in the Gaussian blur formula when calculating the kernel of the bloom.
Distortion	Stretches the image horizontally or vertically.
Afterimage	Simulates afterimage (Wikipedia) — the effect of bright spots "burning" into the retina the longer you look at them, before fading away.
Fade Out Speed	The factor by which the afterimage (if enabled) decreases at each frame (1 means infinite persistence, while 0 means no persistence at all)
Sensitivity	How sensitive the afterimage (if enabled) is to light. The higher this value is, the faster the effect is created when the camera focuses on a light.
Expanded filtering	Reverses FXAA and bloom, and uses a richer convolution kernel during blurring. This helps reduce temporal shimmering.

See also

• Anti-aliasing
• Ambient occlusion
• Bright filter
• Color transforms
• Depth of field
• Lens flare
• Light streaks