feat: new Chroma Key layer

synfig-core/po/POTFILES.in

@@ -64,6 +64,8 @@ src/modules/mod_ffmpeg/trgt_ffmpeg.cpp
 src/modules/mod_ffmpeg/trgt_ffmpeg.h
 src/modules/mod_filter/blur.cpp
 src/modules/mod_filter/blur.h
+src/modules/mod_filter/chromakey.cpp
+src/modules/mod_filter/chromakey.h
 src/modules/mod_filter/colorcorrect.cpp
 src/modules/mod_filter/colorcorrect.h
 src/modules/mod_filter/halftone.cpp

synfig-core/src/modules/mod_filter/CMakeLists.txt

@@ -1,6 +1,7 @@
 add_library(mod_filter MODULE
         "${CMAKE_CURRENT_LIST_DIR}/halftone3.cpp"
         "${CMAKE_CURRENT_LIST_DIR}/blur.cpp"
+        "${CMAKE_CURRENT_LIST_DIR}/chromakey.cpp"
         "${CMAKE_CURRENT_LIST_DIR}/lumakey.cpp"
         "${CMAKE_CURRENT_LIST_DIR}/halftone2.cpp"
         "${CMAKE_CURRENT_LIST_DIR}/halftone.cpp"

synfig-core/src/modules/mod_filter/Makefile.am

@@ -13,6 +13,8 @@ module_LTLIBRARIES = libmod_filter.la
 libmod_filter_la_SOURCES = \
 	blur.cpp \
 	blur.h \
+	chromakey.cpp \
+	chromakey.h \
 	colorcorrect.cpp \
 	colorcorrect.h \
 	halftone2.cpp \

synfig-core/src/modules/mod_filter/chromakey.cpp

@@ -0,0 +1,285 @@
+/* === S Y N F I G ========================================================= */
+/*!	\file chromakey.cpp
+**	\brief Implementation of the "Chroma Key" layer
+**
+**	\legal
+**	Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
+**	Copyright (c) 2022 Rodolfo R Gomes
+**
+**	This file is part of Synfig.
+**
+**	Synfig is free software: you can redistribute it and/or modify
+**	it under the terms of the GNU General Public License as published by
+**	the Free Software Foundation, either version 2 of the License, or
+**	(at your option) any later version.
+**
+**	Synfig is distributed in the hope that it will be useful,
+**	but WITHOUT ANY WARRANTY; without even the implied warranty of
+**	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+**	GNU General Public License for more details.
+**
+**	You should have received a copy of the GNU General Public License
+**	along with Synfig.  If not, see <https://www.gnu.org/licenses/>.
+**	\endlegal
+*/
+/* ========================================================================= */
+
+/* === H E A D E R S ======================================================= */
+
+#ifdef USING_PCH
+#	include "pch.h"
+#else
+#ifdef HAVE_CONFIG_H
+#	include <config.h>
+#endif
+
+#include "chromakey.h"
+
+#include <synfig/context.h>
+#include <synfig/localization.h>
+
+#endif
+
+using namespace synfig;
+
+/* === M A C R O S ========================================================= */
+
+/* === G L O B A L S ======================================================= */
+
+SYNFIG_LAYER_INIT(ChromaKey);
+SYNFIG_LAYER_SET_NAME(ChromaKey,"chromakey");
+SYNFIG_LAYER_SET_LOCAL_NAME(ChromaKey,N_("Chroma Key"));
+SYNFIG_LAYER_SET_CATEGORY(ChromaKey,N_("Filters"));
+SYNFIG_LAYER_SET_VERSION(ChromaKey,"0.1");
+
+/* === P R O C E D U R E S ================================================= */
+
+/* === M E T H O D S ======================================================= */
+
+rendering::Task::Token TaskChromaKey::token(
+	DescAbstract<TaskChromaKey>("ChromaKey") );
+rendering::Task::Token TaskChromaKeySW::token(
+	DescReal<TaskChromaKeySW, TaskChromaKey>("TaskChromaKeySW") );
+
+bool
+TaskChromaKey::is_transparent() const
+{
+	return synfig::approximate_less_or_equal(upper_bound, 0.)
+			&& synfig::approximate_less_or_equal(lower_bound, 0.);
+}
+
+TaskChromaKey::TaskChromaKey()
+	: lower_bound(0.1),
+	  upper_bound(0.1),
+	  desaturate(true)
+{
+}
+
+bool
+TaskChromaKeySW::run(RunParams&) const
+{
+
+	RectInt r = target_rect;
+	if (r.valid())
+	{
+		VectorInt offset = get_offset();
+		RectInt ra = sub_task()->target_rect + r.get_min() + get_offset();
+		if (ra.valid())
+		{
+			rect_set_intersect(ra, ra, r);
+			if (ra.valid())
+			{
+				LockWrite ldst(this);
+				if (!ldst) return false;
+				LockRead lsrc(sub_task());
+				if (!lsrc) return false;
+
+				const Color::value_type u_key = key_color.get_u();
+				const Color::value_type v_key = key_color.get_v();
+				const Real lower_bound2 = lower_bound*lower_bound;
+				const Real upper_bound2 = upper_bound*upper_bound;
+				const Real range = std::abs(upper_bound - lower_bound);
+
+				const synfig::Surface &a = lsrc->get_surface();
+				synfig::Surface &c = ldst->get_surface();
+				for(int y = ra.miny; y < ra.maxy; ++y)
+				{
+					const Color *ca = &a[y - r.miny + offset[1]][ra.minx - r.minx + offset[0]];
+					Color *cc = &c[y][ra.minx];
+					for(int x = ra.minx; x < ra.maxx; ++x, ++ca, ++cc) {
+						*cc = *ca;
+						Real dist2 = (ca->get_u() - u_key)*(ca->get_u() - u_key) + (ca->get_v() - v_key)*(ca->get_v() - v_key);
+						if (approximate_less(dist2, lower_bound2))
+							cc->set_a(0.);
+						else if (approximate_less(dist2, upper_bound2)) {
+							cc->set_a(cc->get_a()*(sqrt(dist2)-lower_bound)/range);
+							if (desaturate)
+								cc->set_s(0);
+						}
+						//else
+						//	cc->set_a(1. * cc->get_a());
+					}
+				}
+			}
+		}
+	}
+
+	return true;
+}
+
+ChromaKey::ChromaKey():
+	Layer(),
+	param_key_color(Color(0.,1.,0.)),
+	param_lower_bound(0.001),
+	param_upper_bound(0.001),
+	param_supersample_width(int(2)),
+	param_supersample_height(int(2)),
+	param_desaturate(true)
+{
+	SET_INTERPOLATION_DEFAULTS();
+	SET_STATIC_DEFAULTS();
+}
+
+bool
+ChromaKey::set_param(const String &param, const ValueBase &value)
+{
+	IMPORT_VALUE(param_key_color);
+	IMPORT_VALUE(param_lower_bound);
+	IMPORT_VALUE(param_upper_bound);
+	IMPORT_VALUE_PLUS(param_supersample_width,
+		{
+			int width = std::max(1, value.get(int()));
+			param_supersample_width.set(width);
+			return true;
+		}
+		);
+	IMPORT_VALUE_PLUS(param_supersample_height,
+		{
+			int height = std::max(1, value.get(int()));
+			param_supersample_height.set(height);
+			return true;
+		}
+		);
+	IMPORT_VALUE(param_desaturate);
+
+	return Layer::set_param(param,value);
+}
+
+ValueBase
+ChromaKey::get_param(const String &param) const
+{
+	EXPORT_VALUE(param_key_color);
+	EXPORT_VALUE(param_lower_bound);
+	EXPORT_VALUE(param_upper_bound);
+	EXPORT_VALUE(param_supersample_width);
+	EXPORT_VALUE(param_supersample_height);
+	EXPORT_VALUE(param_desaturate);
+
+	EXPORT_NAME();
+	EXPORT_VERSION();
+
+	return Layer::get_param(param);
+}
+
+Layer::Vocab
+ChromaKey::get_param_vocab() const
+{
+	Layer::Vocab ret(Layer::get_param_vocab());
+
+	ret.push_back(ParamDesc("key_color")
+		.set_local_name(_("Key Color"))
+		.set_description(_("Color to be made transparent"))
+	);
+
+	ret.push_back(ParamDesc("lower_bound")
+		.set_local_name(_("Lower Bound"))
+		.set_description(_("If chroma difference between pixel and key color is below this value, this pixel becomes fully transparent.\nRange: 0.0 ~ 1.0"))
+	);
+
+	ret.push_back(ParamDesc("upper_bound")
+		.set_local_name(_("Upper Bound"))
+		.set_description(_("If chroma difference between pixel and key color is above this value, this pixel doesn't change.\nRange: 0.0 ~ 1.0"))
+	);
+
+	ret.push_back(ParamDesc("supersample_width")
+		.set_local_name(_("Sample Width"))
+		.set_description(_("Width of the sample area (In pixels).\n1 disables it"))
+	);
+	ret.push_back(ParamDesc("supersample_height")
+		.set_local_name(_("Sample Height"))
+		.set_description(_("Height of the sample area (In pixels)\n1 disables it"))
+	);
+
+	ret.push_back(ParamDesc("desaturate")
+		.set_local_name(_("Desaturate"))
+		.set_description(_("When checked, it desaturates pixels whose chroma is near chroma key (difference is below upper bound)"))
+	);
+
+	return ret;
+}
+
+Color
+ChromaKey::get_color(Context context, const Point &getpos) const
+{
+	Color ret(context.get_color(getpos));
+
+	const Color key_color = param_key_color.get(Color());
+	const Real lower_bound = param_lower_bound.get(Real());
+	const Real upper_bound = param_upper_bound.get(Real());
+
+	if (synfig::approximate_less_or_equal(upper_bound, 0.)
+			&& synfig::approximate_less_or_equal(lower_bound, 0.))
+		return ret;
+
+	const Real u_key = key_color.get_u();
+	const Real v_key = key_color.get_v();
+	const Real lower_bound2 = lower_bound*lower_bound;
+	const Real upper_bound2 = upper_bound*upper_bound;
+	const Real range = std::abs(upper_bound - lower_bound);
+
+	Real dist2 = (ret.get_u() - u_key)*(ret.get_u() - u_key) + (ret.get_v() - v_key)*(ret.get_v() - v_key);
+	if (dist2 < lower_bound2)
+		ret.set_a(0.);
+	else if (dist2 < upper_bound2)
+		ret.set_a(ret.get_a()*(sqrt(dist2)-lower_bound)/range);
+	//else
+	//	ret.set_a(1. * ret.get_a());
+	return ret;
+}
+
+Rect
+ChromaKey::get_bounding_rect(Context context) const
+{
+	if(!active())
+		return Rect::zero();
+
+	return context.get_full_bounding_rect();
+}
+
+rendering::Task::Handle
+ChromaKey::build_rendering_task_vfunc(Context context) const
+{
+	rendering::Task::Handle task = context.build_rendering_task();
+
+	TaskChromaKey::Handle task_chromakey(new TaskChromaKey());
+	task_chromakey->key_color = param_key_color.get(Color());
+	task_chromakey->lower_bound = param_lower_bound.get(Real());
+	task_chromakey->upper_bound = param_upper_bound.get(Real());
+	task_chromakey->desaturate = param_desaturate.get(bool());
+	task_chromakey->sub_task() = task;
+	task = task_chromakey;
+
+	int width = param_supersample_width.get(int());
+	int height = param_supersample_height.get(int());
+
+	if (width == 1 && height == 1)
+		return task;
+
+	rendering::TaskTransformationAffine::Handle task_transformation(new rendering::TaskTransformationAffine());
+	task_transformation->supersample[0] = width;
+	task_transformation->supersample[1] = height;
+	task_transformation->sub_task() = task;
+	task = task_transformation;
+
+	return task;
+}