/* PIKA - Photo and Image Kooker Application * a rebranding of The GNU Image Manipulation Program (created with heckimp) * A derived work which may be trivial. However, any changes may be (C)2023 by Aldercone Studio * * Original copyright, applying to most contents (license remains unchanged): * Copyright (C) 1995 Spencer Kimball and Peter Mattis * * pikaoperationdesaturate.c * Copyright (C) 2007 Michael Natterer * * This program 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 3 of the License, or * (at your option) any later version. * * This program 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 this program. If not, see . */ #include "config.h" #include #include #include #include "libpikabase/pikabase.h" #include "libpikacolor/pikacolor.h" #include "libpikaconfig/pikaconfig.h" #include "operations-types.h" #include "pikaoperationdesaturate.h" #include "pika-intl.h" enum { PROP_0, PROP_MODE }; static void pika_operation_desaturate_get_property (GObject *object, guint property_id, GValue *value, GParamSpec *pspec); static void pika_operation_desaturate_set_property (GObject *object, guint property_id, const GValue *value, GParamSpec *pspec); static void pika_operation_desaturate_prepare (GeglOperation *operation); static gboolean pika_operation_desaturate_process (GeglOperation *operation, void *in_buf, void *out_buf, glong samples, const GeglRectangle *roi, gint level); G_DEFINE_TYPE (PikaOperationDesaturate, pika_operation_desaturate, PIKA_TYPE_OPERATION_POINT_FILTER) #define parent_class pika_operation_desaturate_parent_class static void pika_operation_desaturate_class_init (PikaOperationDesaturateClass *klass) { GObjectClass *object_class = G_OBJECT_CLASS (klass); GeglOperationClass *operation_class = GEGL_OPERATION_CLASS (klass); GeglOperationPointFilterClass *point_class = GEGL_OPERATION_POINT_FILTER_CLASS (klass); object_class->set_property = pika_operation_desaturate_set_property; object_class->get_property = pika_operation_desaturate_get_property; operation_class->prepare = pika_operation_desaturate_prepare; point_class->process = pika_operation_desaturate_process; gegl_operation_class_set_keys (operation_class, "name", "pika:desaturate", "categories", "color", "description", _("Turn colors into shades of gray"), NULL); PIKA_CONFIG_PROP_ENUM (object_class, PROP_MODE, "mode", _("Mode"), _("Choose shade of gray based on"), PIKA_TYPE_DESATURATE_MODE, PIKA_DESATURATE_LUMINANCE, PIKA_PARAM_STATIC_STRINGS); } static void pika_operation_desaturate_init (PikaOperationDesaturate *self) { } static void pika_operation_desaturate_get_property (GObject *object, guint property_id, GValue *value, GParamSpec *pspec) { PikaOperationDesaturate *desaturate = PIKA_OPERATION_DESATURATE (object); switch (property_id) { case PROP_MODE: g_value_set_enum (value, desaturate->mode); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec); break; } } static void pika_operation_desaturate_set_property (GObject *object, guint property_id, const GValue *value, GParamSpec *pspec) { PikaOperationDesaturate *desaturate = PIKA_OPERATION_DESATURATE (object); switch (property_id) { case PROP_MODE: desaturate->mode = g_value_get_enum (value); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec); break; } } static void pika_operation_desaturate_prepare (GeglOperation *operation) { PikaOperationDesaturate *desaturate = PIKA_OPERATION_DESATURATE (operation); const Babl *format = gegl_operation_get_source_format (operation, "input"); if (desaturate->mode == PIKA_DESATURATE_LUMINANCE) { format = babl_format_with_space ("RGBA float", format); } else { format = babl_format_with_space ("R'G'B'A float", format); } gegl_operation_set_format (operation, "input", format); gegl_operation_set_format (operation, "output", format); } static gboolean pika_operation_desaturate_process (GeglOperation *operation, void *in_buf, void *out_buf, glong samples, const GeglRectangle *roi, gint level) { PikaOperationDesaturate *desaturate = PIKA_OPERATION_DESATURATE (operation); gfloat *src = in_buf; gfloat *dest = out_buf; switch (desaturate->mode) { case PIKA_DESATURATE_LIGHTNESS: /* This is the formula for Lightness in the HSL "bi-hexcone" * model: https://en.wikipedia.org/wiki/HSL_and_HSV */ while (samples--) { gfloat min, max, value; max = MAX (src[0], src[1]); max = MAX (max, src[2]); min = MIN (src[0], src[1]); min = MIN (min, src[2]); value = (max + min) / 2; dest[0] = value; dest[1] = value; dest[2] = value; dest[3] = src[3]; src += 4; dest += 4; } break; case PIKA_DESATURATE_LUMA: case PIKA_DESATURATE_LUMINANCE: { const Babl *space = gegl_operation_get_source_space (operation, "input"); double red_luminance, green_luminance, blue_luminance; babl_space_get_rgb_luminance (space, &red_luminance, &green_luminance, &blue_luminance); while (samples--) { gfloat value = (src[0] * red_luminance) + (src[1] * green_luminance) + (src[2] * blue_luminance); dest[0] = value; dest[1] = value; dest[2] = value; dest[3] = src[3]; src += 4; dest += 4; } } break; case PIKA_DESATURATE_AVERAGE: /* This is the formula for Intensity in the HSI model: * https://en.wikipedia.org/wiki/HSL_and_HSV */ while (samples--) { gfloat value = (src[0] + src[1] + src[2]) / 3; dest[0] = value; dest[1] = value; dest[2] = value; dest[3] = src[3]; src += 4; dest += 4; } break; case PIKA_DESATURATE_VALUE: /* This is the formula for Value in the HSV model: * https://en.wikipedia.org/wiki/HSL_and_HSV */ while (samples--) { gfloat value; value = MAX (src[0], src[1]); value = MAX (value, src[2]); dest[0] = value; dest[1] = value; dest[2] = value; dest[3] = src[3]; src += 4; dest += 4; } break; } return TRUE; }