Feedback: Trails

In the S_Feedback Plugin.

The previous frames of the input clip are combined with the current frame to give a variety of 'time trails' effects. The output of each processed frame is stored and then combined with the next frame. The trails are reinitialized whenever any non-consecutive frame is processed, either the first frame, reprocessing a given frame, or jumping to another frame. You must process multiple frames of a clip in a row to observe the effect.

Inputs:

Source:  The clip to be processed.
        

Parameters:

Fade:   Default: 0.8,  Range: 0 or greater,  Shared.
For each frame, the previous output is scaled by this amount before it is combined with the new input frame. Normally this value should be less than 1.0 which causes previous frames to fade out over time. A value of 1.0 causes no fading, and values greater than 1.0 cause previous frames to become brighter over time.

Brightness:   Default: 1,  Range: 0 or greater,  Shared.
Scales the brightness of all frames.

Blur Amount:   Default: 0,  Range: 0 or greater.
The previous frames are blurred by this amount for each new frame. This has no effect unless it is positive.

Blur Rel:   X & Y,   Default: [1 1],  Range: 0 or greater.
The relative horizontal and vertical amounts of the blurring. This has no effect unless Blur Amount is positive.

Combine:   Popup menu,  Default: Ave.
Selects the method for combining previous frames with the current frame.

Ave:  The current frame is averaged with the previous output, smearing moving objects out over time. The output is scaled by Fade and the input is scaled by 1.0-Fade for a weighted average, so Fade must be less than 1.0 for this to work properly. Unlike the other combine options, Ave should never affect the brightness of stationary objects in the clip.

Max:  The colors of the current frame and previous frames are combined with a maximum function. This makes the output frame at least as bright as the current frame, and will make brighter 'trails' for example if you have bright objects moving on a dark background.

Screen:  The colors of the current frame and previous frames are combined with a blend function. This can be used to accumulate the colors of a moving clip. However, non-black regions will become brighter with each frame.

Add:  The colors of the current frame and previous frames are added. This can also be used to accumulate the colors of a moving clip, with the non-black regions becoming brighter at each frame.

Min:  The colors of the current frame and previous frames are combined with a minimum function. This makes the output frame no brighter than the current frame, and will often fade quickly to a black frame.

Fade Color:   Default rgb: [1 1 1],  Shared.
For each frame, the previous output is scaled by this color before it is combined with the new input frame. This is similar to Fade but affects the colors of the previous frames instead of just the brightness.

Color:   Default rgb: [1 1 1],  Shared.
Scales the color of all frames. Set this color to the complement of Fade Color to offset overly colored trails.

Hue Shift:   Default: 0,  Range: any,  Shared.
Shifts the hue of the previous frames' colors, for each new frame.

See general info for: Res, Redraw, Undo, Load Defaults, Crop, Add Noise, and Use Gamma.


See Also:

Feedback
TrailsDiffuse
FeedbackDistort
TimeAverage
NearestColor
FeedbackBubble
TrailsMatte
WarpRepeat
WarpChroma
Sapphire Plug-ins Introduction


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