TimeBlur
When a fast moving subject is recorded on film or video, its edges appear to smear as a result of the object's movement while the shutter is open. The longer the shutter remains open at each frame interval, the more obvious this effect. TimeBlur simulates this phenomenon by sampling its input at divisions times over shutter frames starting at the current frame plus offset.
Time blur is commonly applied to garbage masks that are tracked to a fast moving feature. The time blur averages the incoming mask image over the shutter period, to better match the motion blur in the original image and creating a more convincing integration.
See also NoTimeBlur.
Inputs and Controls
Connection Type |
Connection Name |
Function |
Input |
unnamed |
The image sequence to which you want to apply blur. |
Control (UI) |
Knob (Scripting) |
Default Value |
Function |
TimeBlur Tab |
|||
divisions |
divisions |
10 |
The number of times you want to sample the input over the shutter time. For images with fast-moving content, higher values are necessary to eliminate "steppiness" or banding in the output. |
shutter |
shutter |
0.5 |
Sets the number of frames the shutter stays open when motion blurring. For example, a value of 0.5 corresponds to half a frame. Increasing the value produces more blur, and decreasing the value less. |
shutter offset |
shutteroffset |
start |
Controls how the shutter behaves with respect to the current frame value: • centred - center the shutter around the current frame. For example, if you set the shutter value to 1 and your current frame is 30, the shutter stays open from frame 29,5 to 30,5. • start - open the shutter at the current frame. For example, if you set the shutter value to 1 and your current frame is 30, the shutter stays open from frame 30 to 31. • end - close the shutter at the current frame. For example, if you set the shutter value to 1 and your current frame is 30, the shutter stays open from frame 29 to 30. • custom - open the shutter at the time you specify. In the field next to the dropdown menu, enter a value (in frames) you want to add to the current frame. To open the shutter before the current frame, enter a negative value. For example, a value of - 0.5 would open the shutter half a frame before the current frame. |
shuttercustomoffset |
0 |
If the shutter offset control is set to custom, this field is used to set the time that the shutter opens by adding it to the current frame. Values are in frames, so -0.5 would open the shutter half a frame before the current frame. |