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Diffstat (limited to 'app/operations/gimpoperationdesaturate.c')
-rw-r--r-- | app/operations/gimpoperationdesaturate.c | 257 |
1 files changed, 257 insertions, 0 deletions
diff --git a/app/operations/gimpoperationdesaturate.c b/app/operations/gimpoperationdesaturate.c new file mode 100644 index 0000000..9f833db --- /dev/null +++ b/app/operations/gimpoperationdesaturate.c @@ -0,0 +1,257 @@ +/* GIMP - The GNU Image Manipulation Program + * Copyright (C) 1995 Spencer Kimball and Peter Mattis + * + * gimpoperationdesaturate.c + * Copyright (C) 2007 Michael Natterer <mitch@gimp.org> + * + * 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 <https://www.gnu.org/licenses/>. + */ + +#include "config.h" + +#include <cairo.h> +#include <gegl.h> +#include <gdk-pixbuf/gdk-pixbuf.h> + +#include "libgimpcolor/gimpcolor.h" +#include "libgimpconfig/gimpconfig.h" + +#include "operations-types.h" + +#include "gimpoperationdesaturate.h" + +#include "gimp-intl.h" + + +enum +{ + PROP_0, + PROP_MODE +}; + + +static void gimp_operation_desaturate_get_property (GObject *object, + guint property_id, + GValue *value, + GParamSpec *pspec); +static void gimp_operation_desaturate_set_property (GObject *object, + guint property_id, + const GValue *value, + GParamSpec *pspec); + +static void gimp_operation_desaturate_prepare (GeglOperation *operation); +static gboolean gimp_operation_desaturate_process (GeglOperation *operation, + void *in_buf, + void *out_buf, + glong samples, + const GeglRectangle *roi, + gint level); + + +G_DEFINE_TYPE (GimpOperationDesaturate, gimp_operation_desaturate, + GIMP_TYPE_OPERATION_POINT_FILTER) + +#define parent_class gimp_operation_desaturate_parent_class + + +static void +gimp_operation_desaturate_class_init (GimpOperationDesaturateClass *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 = gimp_operation_desaturate_set_property; + object_class->get_property = gimp_operation_desaturate_get_property; + + operation_class->prepare = gimp_operation_desaturate_prepare; + + point_class->process = gimp_operation_desaturate_process; + + gegl_operation_class_set_keys (operation_class, + "name", "gimp:desaturate", + "categories", "color", + "description", _("Turn colors into shades of gray"), + NULL); + + GIMP_CONFIG_PROP_ENUM (object_class, PROP_MODE, + "mode", + _("Mode"), + _("Choose shade of gray based on"), + GIMP_TYPE_DESATURATE_MODE, + GIMP_DESATURATE_LUMINANCE, + GIMP_PARAM_STATIC_STRINGS); +} + +static void +gimp_operation_desaturate_init (GimpOperationDesaturate *self) +{ +} + +static void +gimp_operation_desaturate_get_property (GObject *object, + guint property_id, + GValue *value, + GParamSpec *pspec) +{ + GimpOperationDesaturate *desaturate = GIMP_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 +gimp_operation_desaturate_set_property (GObject *object, + guint property_id, + const GValue *value, + GParamSpec *pspec) +{ + GimpOperationDesaturate *desaturate = GIMP_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 +gimp_operation_desaturate_prepare (GeglOperation *operation) +{ + GimpOperationDesaturate *desaturate = GIMP_OPERATION_DESATURATE (operation); + const Babl *format = gegl_operation_get_source_format (operation, "input"); + + if (desaturate->mode == GIMP_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 +gimp_operation_desaturate_process (GeglOperation *operation, + void *in_buf, + void *out_buf, + glong samples, + const GeglRectangle *roi, + gint level) +{ + GimpOperationDesaturate *desaturate = GIMP_OPERATION_DESATURATE (operation); + gfloat *src = in_buf; + gfloat *dest = out_buf; + + switch (desaturate->mode) + { + case GIMP_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 GIMP_DESATURATE_LUMA: + case GIMP_DESATURATE_LUMINANCE: + while (samples--) + { + gfloat value = GIMP_RGB_LUMINANCE (src[0], src[1], src[2]); + + dest[0] = value; + dest[1] = value; + dest[2] = value; + dest[3] = src[3]; + + src += 4; + dest += 4; + } + break; + + case GIMP_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 GIMP_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; +} |