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Diffstat (limited to 'app/operations/gimpoperationequalize.c')
| -rw-r--r-- | app/operations/gimpoperationequalize.c | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/app/operations/gimpoperationequalize.c b/app/operations/gimpoperationequalize.c new file mode 100644 index 0000000..119be23 --- /dev/null +++ b/app/operations/gimpoperationequalize.c @@ -0,0 +1,248 @@ +/* GIMP - The GNU Image Manipulation Program + * Copyright (C) 1995 Spencer Kimball and Peter Mattis + * + * gimpoperationequalize.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 "libgimpmath/gimpmath.h" + +#include "operations-types.h" + +#include "core/gimphistogram.h" + +#include "gimpoperationequalize.h" + + +enum +{ + PROP_0, + PROP_HISTOGRAM +}; + + +static void gimp_operation_equalize_finalize (GObject *object); +static void gimp_operation_equalize_get_property (GObject *object, + guint property_id, + GValue *value, + GParamSpec *pspec); +static void gimp_operation_equalize_set_property (GObject *object, + guint property_id, + const GValue *value, + GParamSpec *pspec); + +static gboolean gimp_operation_equalize_process (GeglOperation *operation, + void *in_buf, + void *out_buf, + glong samples, + const GeglRectangle *roi, + gint level); + + +G_DEFINE_TYPE (GimpOperationEqualize, gimp_operation_equalize, + GIMP_TYPE_OPERATION_POINT_FILTER) + +#define parent_class gimp_operation_equalize_parent_class + + +static void +gimp_operation_equalize_class_init (GimpOperationEqualizeClass *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->finalize = gimp_operation_equalize_finalize; + object_class->set_property = gimp_operation_equalize_set_property; + object_class->get_property = gimp_operation_equalize_get_property; + + gegl_operation_class_set_keys (operation_class, + "name", "gimp:equalize", + "categories", "color", + "description", "GIMP Equalize operation", + NULL); + + point_class->process = gimp_operation_equalize_process; + + g_object_class_install_property (object_class, PROP_HISTOGRAM, + g_param_spec_object ("histogram", + "Histogram", + "The histogram", + GIMP_TYPE_HISTOGRAM, + G_PARAM_READWRITE | + G_PARAM_CONSTRUCT_ONLY)); +} + +static void +gimp_operation_equalize_init (GimpOperationEqualize *self) +{ + self->values = NULL; + self->n_bins = 0; +} + +static void +gimp_operation_equalize_finalize (GObject *object) +{ + GimpOperationEqualize *self = GIMP_OPERATION_EQUALIZE (object); + + g_clear_pointer (&self->values, g_free); + g_clear_object (&self->histogram); + + G_OBJECT_CLASS (parent_class)->finalize (object); +} + +static void +gimp_operation_equalize_get_property (GObject *object, + guint property_id, + GValue *value, + GParamSpec *pspec) +{ + GimpOperationEqualize *self = GIMP_OPERATION_EQUALIZE (object); + + switch (property_id) + { + case PROP_HISTOGRAM: + g_value_set_pointer (value, self->histogram); + break; + + default: + G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec); + break; + } +} + +static void +gimp_operation_equalize_set_property (GObject *object, + guint property_id, + const GValue *value, + GParamSpec *pspec) +{ + GimpOperationEqualize *self = GIMP_OPERATION_EQUALIZE (object); + + switch (property_id) + { + case PROP_HISTOGRAM: + if (self->histogram) + g_object_unref (self->histogram); + + self->histogram = g_value_dup_object (value); + + if (self->histogram) + { + gdouble pixels; + gint n_bins; + gint max; + gint k; + + n_bins = gimp_histogram_n_bins (self->histogram); + + if ((self->values != NULL) && (self->n_bins != n_bins)) + { + g_free (self->values); + self->values = NULL; + } + + if (self->values == NULL) + { + self->values = g_new (gdouble, 3 * n_bins); + } + + self->n_bins = n_bins; + + pixels = gimp_histogram_get_count (self->histogram, + GIMP_HISTOGRAM_VALUE, 0, n_bins - 1); + + if (gimp_histogram_n_components (self->histogram) == 1 || + gimp_histogram_n_components (self->histogram) == 2) + max = 1; + else + max = 3; + + for (k = 0; k < 3; k++) + { + gdouble sum = 0; + gint i; + + for (i = 0; i < n_bins; i++) + { + gdouble histi; + + histi = gimp_histogram_get_component (self->histogram, k, i); + + sum += histi; + + self->values[k * n_bins + i] = sum / pixels; + + if (max == 1) + { + self->values[n_bins + i] = self->values[i]; + self->values[2 * n_bins + i] = self->values[i]; + } + } + } + } + break; + + default: + G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec); + break; + } +} + +static inline float +gimp_operation_equalize_map (GimpOperationEqualize *self, + gint component, + gfloat value) +{ + gint index; + index = component * self->n_bins + \ + (gint) (CLAMP (value * (self->n_bins - 1), 0.0, self->n_bins - 1)); + + return self->values[index]; +} + +static gboolean +gimp_operation_equalize_process (GeglOperation *operation, + void *in_buf, + void *out_buf, + glong samples, + const GeglRectangle *roi, + gint level) +{ + GimpOperationEqualize *self = GIMP_OPERATION_EQUALIZE (operation); + gfloat *src = in_buf; + gfloat *dest = out_buf; + + while (samples--) + { + dest[RED] = gimp_operation_equalize_map (self, RED, src[RED]); + dest[GREEN] = gimp_operation_equalize_map (self, GREEN, src[GREEN]); + dest[BLUE] = gimp_operation_equalize_map (self, BLUE, src[BLUE]); + dest[ALPHA] = src[ALPHA]; + + src += 4; + dest += 4; + } + + return TRUE; +} |