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+# Adaptivegrain-rs
+Reimplementation of the adaptive\_grain mask as a Vapoursynth plugin.
+For a description of the math and the general idea,
+see [the article](https://kageru.moe/blog/article/adaptivegrain/).
+
+## Usage
+`core.adg.Mask(clip, luma_scaling: float)`
+
+You must call `std.PlaneStats()` before this plugin
+  (or fill the PlaneStatsAverage frame property using some other method).
+
+Supported formats are YUV with 8-32 bit precision integer or single precision float.
+Half precision float input is not supported since no one seems to be using that anyway.
+
+Since the output is grey and only luma is processed,
+  the subsampling of the input does not matter.
+
+To replicate the original behaviour of adaptivegrain, a wrapper is provided in kagefunc.
+It behaves exactly like the original implementation
+  (except for the performance, which is about 3x faster on my machine).
+
+### Parameters
+`clip: vapoursynth.VideoNode` 
+the input clip to generate a mask for.
+
+`luma_scaling: float = 10.0`
+the luma\_scaling factor as described in the blog post.
+Higher values will make the mask brighter overall.
+
+## Build instructions
+```sh
+cargo build --release
+```
+That’s it. This is Rust, after all.
+No idea what the minimum version is,
+   but it works with stable rust 1.41.
+   That’s all I know.
+Binaries for Windows and Linux are in the release tab.
+
+## FAQ
+**Why do I have to call std.PlaneStats() manually?**
+Because I didn’t want to reimplement it.
+`kagefunc.adaptive_grain(clip, show_mask=True)`
+  does that for you and then just returns the mask.
+
+**Why doesn’t this also add grain?**
+I was going to do that originally,
+  but it just goes back to the same point
+  about not wanting to reimplement
+  something that already exists.