X-Git-Url: https://git.sesse.net/?p=movit;a=blobdiff_plain;f=saturation_effect.h;h=4dd72e4da09b4b0805ecf6d6d7b0104e68f9cd1e;hp=6cfc3d0ee0392c49d18e5a0b3f782c40fc5889e9;hb=ed30033a26851b96c2c3a0ed2a5751446038fcc3;hpb=17c083aad45a10df14c38cfe879a87220dfd4fb9

diff --git a/saturation_effect.h b/saturation_effect.h
index 6cfc3d0..4dd72e4 100644
--- a/saturation_effect.h
+++ b/saturation_effect.h
@@ -1,11 +1,18 @@
 #ifndef _SATURATION_EFFECT_H
 #define _SATURATION_EFFECT_H 1
 
+// A simple desaturation/saturation effect. We use the Rec. 709
+// definition of luminance (in linear light, of course) and linearly
+// interpolate between that (saturation=0) and the original signal
+// (saturation=1). Extrapolating that curve further (ie., saturation > 1)
+// gives us increased saturation if so desired.
+
 #include "effect.h"
 
 class SaturationEffect : public Effect {
 public:
 	SaturationEffect();
+	virtual std::string effect_type_id() const { return "SaturationEffect"; }
 	std::string output_fragment_shader();
 
 private: