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README.md

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-VapourSynth-AddGrain
-====================
+Description
+===========
 
-VapourSynth port of AddGrainC
+AddGrain generates film like grain or other effects (like rain) by adding random noise to a video clip. This noise may optionally be horizontally or vertically correlated to cause streaking.
+
+Ported from AviSynth plugin http://forum.doom9.org/showthread.php?t=111849
+
+
+Usage
+=====
+
+    grain.Add(clip clip[, float var=1.0, float uvar=0.0, float hcorr=0.0, float vcorr=0.0, int seed=-1, bint constant=False])
+
+- var, uvar: The standard deviation (strength) of the luma and chroma noise, 0 is disabled.
+
+- hcorr, vcorr: Horizontal and vertical correlation, which causes a nifty streaking effect. Range 0.0-1.0
+
+- seed: Specifies a repeatable grain sequence. Set to at least 0 to use.
+
+- constant: Specifies a constant grain pattern on every frame.