SpatialSoften / TemporalSoften

SpatialSoften (clip, int radius, int luma_threshold, int chroma_threshold)
TemporalSoften (clip, int radius, int luma_threshold, int chroma_threshold, int "scenechange", int "mode")

The SpatialSoftenand TemporalSoftenfilters remove noise from a video clip by selectively blending pixels. These filters can work miracles, and I highly encourage you to try them. But they can also wipe out fine detail if set too high, so don't go overboard. And they are very slow, especially with a large value of radius, so don't turn them on until you've got everything else ready.

SpatialSoften replaces each sample in a frame with the average of all nearby samples with differ from the central sample by no more than a certain threshold value. "Nearby" means no more than radius pixels away in the x and y directions. The threshold used is luma_threshold for the Y (intensity) samples, and chroma_threshold for the U and V (color) samples.

TemporalSoften is similar, except that it looks at the same pixel in nearby frames, instead of nearby pixels in the same frame. All frames no more than radius away are examined. This filter doesn't seem to be as effective as SpatialSoften.

I encourage you to play around with the parameters for these filters to get an idea of what they do--for example, try setting one of the three parameters to a very high value while leaving the others low, and see what happens. Note that setting any of the three parameters to zero will cause the filter to become a very slow no-op.

TemporalSoften smoothes luma and chroma separately, but SpatialSoftensmoothes only if both luma and chroma have passed the threshold.

The SpatialSoftenfilter work only with YUY2 input. You can use the ConvertToYUY2filter if your input is not in YUY2 format.

Note that if you use AviSynth v2.04 or above, you don't need the TemporalSoften2 plugin anymore, the built-in TemporalSoften is replaced with that implementation.

Starting from v2.50, two options are added to TemporalSoften:

• An optional mode=2 parameter: It has a new and better way of blending frame and provides better quality. It is also much faster. Requires ISSE. mode=1 is default operation, and works as always.
• An optional scenechange=n parameter: Using this parameter will avoid blending across scene changes. 'n' defines the maximum average pixel change between frames. Good values for 'n' are between 5 and 30. Requires ISSE.

Good initial values: TemporalSoften(4,4,8,15,2)

Changes:

$Date: 2007/07/14 18:06:23 $