From 1a6a7d4a8e2b26caad00d30283ace1f7d2478270 Mon Sep 17 00:00:00 2001 From: David Plowman Date: Tue, 8 Dec 2020 20:44:39 +0000 Subject: ipa: raspberrypi: Compute inverse of piecewise linear function Add a method to the piecewise linear function (Pwl) class to compute the inverse of a given Pwl. If the input function is non-monotonic we can only produce a best effort "pseudo" inverse, and we signal this to the caller. Signed-off-by: David Plowman Reviewed-by: Naushir Patuck Reviewed-by: Laurent Pinchart Signed-off-by: Laurent Pinchart --- src/ipa/raspberrypi/controller/pwl.hpp | 3 +++ 1 file changed, 3 insertions(+) (limited to 'src/ipa/raspberrypi/controller/pwl.hpp') diff --git a/src/ipa/raspberrypi/controller/pwl.hpp b/src/ipa/raspberrypi/controller/pwl.hpp index 4f168551..484672f6 100644 --- a/src/ipa/raspberrypi/controller/pwl.hpp +++ b/src/ipa/raspberrypi/controller/pwl.hpp @@ -80,6 +80,9 @@ public: }; PerpType Invert(Point const &xy, Point &perp, int &span, const double eps = 1e-6) const; + // Compute the inverse function. Indicate if it is a proper (true) + // inverse, or only a best effort (e.g. input was non-monotonic). + Pwl Inverse(bool *true_inverse = nullptr, const double eps = 1e-6) const; // Compose two Pwls together, doing "this" first and "other" after. Pwl Compose(Pwl const &other, const double eps = 1e-6) const; // Apply function to (x,y) values at every control point. -- cgit v1.2.1