Bloom
Extracts the layer's highlights, blurs them, and adds them back as a glow in linear light. HDR highlights keep their brightness. The glow extends past the layer's edges unless Preserve alpha is on. This effect requires GPU textures and GLSL execution.
Library location
Library → Filter Effect → Bloom
Properties
Radius
Glow radius in composition units.
- Type:
float - Default:
12 - Animatable: Yes
- Range:
[0, ∞)
Threshold
Brightness used to select highlights in linear light. 1 is reference white.
- Type:
float - Default:
0.5 - Animatable: Yes
- Range:
[0, ∞)
Softness (%) (SoftKnee)
Smooths the brightness threshold. 0 keeps a hard cutoff; 100 spreads the transition from zero to twice the threshold.
- Type:
float - Default:
0 - Animatable: Yes
- Range:
[0, 100]
Intensity
Glow strength multiplier. 0 disables the glow; 1 is normal strength.
- Type:
float - Default:
1 - Animatable: Yes
- Range:
[0, ∞)
Preserve alpha (PreserveAlpha)
When true, masks the glow with the original alpha instead of extending the layer's silhouette.
- Type:
bool - Default:
false - Animatable: Yes
Usage
Lower Threshold until the areas you want to glow are selected, then adjust Radius and Intensity. Raise Softness when the edge between glowing and non-glowing areas looks abrupt.