summaryrefslogtreecommitdiffstats
path: root/app/operations/gimpoperationequalize.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--app/operations/gimpoperationequalize.c248
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;
+}