From 7382112caf773c61202481f83e81ab013fb0b56c Mon Sep 17 00:00:00 2001 From: Mattias Andrée Date: Fri, 4 Apr 2014 21:53:23 +0200 Subject: document interpolation and halo elimination MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Mattias Andrée --- info/blueshift.texinfo | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) (limited to 'info') diff --git a/info/blueshift.texinfo b/info/blueshift.texinfo index 0ba27ac..8433a6b 100644 --- a/info/blueshift.texinfo +++ b/info/blueshift.texinfo @@ -324,6 +324,7 @@ Disables or enables Blueshift. * Weather:: Making weather dependent settings. * Running without X:: Configuration options for running without X. * Optimising:: Functions that can be used to optimise performance. +* Interpolation:: Interpolation functionised curves. @end menu @@ -1532,6 +1533,48 @@ might be heavier than applying the adjustments by invoking them. +@node Interpolation +@section Interpolation + +ICC profiles and curves that have beens turned +into functions with @code{functionise} have lower +input resolution that the input they receive; +to compensate for this, nearest-neighbour +interpolation is used. If you want to better +interpolation there are a few functions that +can be used to scale up the lookup table using +interpolation. + +@table @code +@item linearly_interpolate_ramp +Scale up using linear interpolation. + +@item cubicly_interpolate_ramp +Scale up using cubic Hermite interpolation. + +@end table + +These functions thats three arguments: +the red, the green and the blue colour +curves to scale up. The functions return +a tuple of these scaled up. All functions +are will using linear interpolation if +an interpolation segments is non-monotonic. +This is done, automatically by the +functions, by using the function +@code{eliminate_halos} that takes six +arguments and does not return anything. +@code{eliminate_halos}'s arguments are +the original three colour curves, followed +by the scaled up colour curves. The latter +argument trio will be modified by the +function. It does not matter which order +there curves are in as long as the order +is the same for the original curves and the +scaled up curves. It is recommended to +use the order: red, green and blue. + + @node Configuration examples @chapter Configuration examples -- cgit v1.2.3-70-g09d2