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-rw-r--r--app/core/gimphistogram.c1261
1 files changed, 1261 insertions, 0 deletions
diff --git a/app/core/gimphistogram.c b/app/core/gimphistogram.c
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+++ b/app/core/gimphistogram.c
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+/* GIMP - The GNU Image Manipulation Program
+ * Copyright (C) 1995 Spencer Kimball and Peter Mattis
+ *
+ * gimphistogram module Copyright (C) 1999 Jay Cox <jaycox@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 <string.h>
+#include <cairo.h>
+#include <gegl.h>
+#include <gdk-pixbuf/gdk-pixbuf.h>
+
+#include "libgimpmath/gimpmath.h"
+#include "libgimpcolor/gimpcolor.h"
+
+#include "core-types.h"
+
+#include "gegl/gimp-babl.h"
+#include "gegl/gimp-gegl-loops.h"
+
+#include "gimp-atomic.h"
+#include "gimp-parallel.h"
+#include "gimpasync.h"
+#include "gimphistogram.h"
+#include "gimpwaitable.h"
+
+
+#define MAX_N_COMPONENTS 4
+#define N_DERIVED_CHANNELS 2
+
+#define PIXELS_PER_THREAD \
+ (/* each thread costs as much as */ 64.0 * 64.0 /* pixels */)
+
+
+enum
+{
+ PROP_0,
+ PROP_N_COMPONENTS,
+ PROP_N_BINS,
+ PROP_VALUES
+};
+
+struct _GimpHistogramPrivate
+{
+ gboolean linear;
+ gint n_channels;
+ gint n_bins;
+ gdouble *values;
+ GimpAsync *calculate_async;
+};
+
+typedef struct
+{
+ /* input */
+ GimpHistogram *histogram;
+ GeglBuffer *buffer;
+ GeglRectangle buffer_rect;
+ GeglBuffer *mask;
+ GeglRectangle mask_rect;
+
+ /* output */
+ gint n_components;
+ gint n_bins;
+ gdouble *values;
+} CalculateContext;
+
+typedef struct
+{
+ GimpAsync *async;
+ CalculateContext *context;
+
+ const Babl *format;
+ GSList *values_list;
+} CalculateData;
+
+
+/* local function prototypes */
+
+static void gimp_histogram_finalize (GObject *object);
+static void gimp_histogram_set_property (GObject *object,
+ guint property_id,
+ const GValue *value,
+ GParamSpec *pspec);
+static void gimp_histogram_get_property (GObject *object,
+ guint property_id,
+ GValue *value,
+ GParamSpec *pspec);
+
+static gint64 gimp_histogram_get_memsize (GimpObject *object,
+ gint64 *gui_size);
+
+static gboolean gimp_histogram_map_channel (GimpHistogram *histogram,
+ GimpHistogramChannel *channel);
+
+static void gimp_histogram_set_values (GimpHistogram *histogram,
+ gint n_components,
+ gint n_bins,
+ gdouble *values);
+
+static void gimp_histogram_calculate_internal (GimpAsync *async,
+ CalculateContext *context);
+static void gimp_histogram_calculate_area (const GeglRectangle *area,
+ CalculateData *data);
+static void gimp_histogram_calculate_async_callback (GimpAsync *async,
+ CalculateContext *context);
+
+
+G_DEFINE_TYPE_WITH_PRIVATE (GimpHistogram, gimp_histogram, GIMP_TYPE_OBJECT)
+
+#define parent_class gimp_histogram_parent_class
+
+
+static void
+gimp_histogram_class_init (GimpHistogramClass *klass)
+{
+ GObjectClass *object_class = G_OBJECT_CLASS (klass);
+ GimpObjectClass *gimp_object_class = GIMP_OBJECT_CLASS (klass);
+
+ object_class->finalize = gimp_histogram_finalize;
+ object_class->set_property = gimp_histogram_set_property;
+ object_class->get_property = gimp_histogram_get_property;
+
+ gimp_object_class->get_memsize = gimp_histogram_get_memsize;
+
+ g_object_class_install_property (object_class, PROP_N_COMPONENTS,
+ g_param_spec_int ("n-components", NULL, NULL,
+ 0, MAX_N_COMPONENTS, 0,
+ GIMP_PARAM_READABLE));
+
+ g_object_class_install_property (object_class, PROP_N_BINS,
+ g_param_spec_int ("n-bins", NULL, NULL,
+ 256, 1024, 1024,
+ GIMP_PARAM_READABLE));
+
+ /* this is just for notifications */
+ g_object_class_install_property (object_class, PROP_VALUES,
+ g_param_spec_boolean ("values", NULL, NULL,
+ FALSE,
+ G_PARAM_READABLE));
+}
+
+static void
+gimp_histogram_init (GimpHistogram *histogram)
+{
+ histogram->priv = gimp_histogram_get_instance_private (histogram);
+}
+
+static void
+gimp_histogram_finalize (GObject *object)
+{
+ GimpHistogram *histogram = GIMP_HISTOGRAM (object);
+
+ gimp_histogram_clear_values (histogram, 0);
+
+ G_OBJECT_CLASS (parent_class)->finalize (object);
+}
+
+static void
+gimp_histogram_set_property (GObject *object,
+ guint property_id,
+ const GValue *value,
+ GParamSpec *pspec)
+{
+ switch (property_id)
+ {
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+ break;
+ }
+}
+
+static void
+gimp_histogram_get_property (GObject *object,
+ guint property_id,
+ GValue *value,
+ GParamSpec *pspec)
+{
+ GimpHistogram *histogram = GIMP_HISTOGRAM (object);
+
+ switch (property_id)
+ {
+ case PROP_N_COMPONENTS:
+ g_value_set_int (value, gimp_histogram_n_components (histogram));
+ break;
+
+ case PROP_N_BINS:
+ g_value_set_int (value, histogram->priv->n_bins);
+ break;
+
+ case PROP_VALUES:
+ /* return a silly boolean */
+ g_value_set_boolean (value, histogram->priv->values != NULL);
+ break;
+
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+ break;
+ }
+}
+
+static gint64
+gimp_histogram_get_memsize (GimpObject *object,
+ gint64 *gui_size)
+{
+ GimpHistogram *histogram = GIMP_HISTOGRAM (object);
+ gint64 memsize = 0;
+
+ if (histogram->priv->values)
+ memsize += (histogram->priv->n_channels *
+ histogram->priv->n_bins * sizeof (gdouble));
+
+ return memsize + GIMP_OBJECT_CLASS (parent_class)->get_memsize (object,
+ gui_size);
+}
+
+/* public functions */
+
+GimpHistogram *
+gimp_histogram_new (gboolean linear)
+{
+ GimpHistogram *histogram = g_object_new (GIMP_TYPE_HISTOGRAM, NULL);
+
+ histogram->priv->linear = linear;
+
+ return histogram;
+}
+
+/**
+ * gimp_histogram_duplicate:
+ * @histogram: a %GimpHistogram
+ *
+ * Creates a duplicate of @histogram. The duplicate has a reference
+ * count of 1 and contains the values from @histogram.
+ *
+ * Return value: a newly allocated %GimpHistogram
+ **/
+GimpHistogram *
+gimp_histogram_duplicate (GimpHistogram *histogram)
+{
+ GimpHistogram *dup;
+
+ g_return_val_if_fail (GIMP_IS_HISTOGRAM (histogram), NULL);
+
+ if (histogram->priv->calculate_async)
+ gimp_waitable_wait (GIMP_WAITABLE (histogram->priv->calculate_async));
+
+ dup = gimp_histogram_new (histogram->priv->linear);
+
+ dup->priv->n_channels = histogram->priv->n_channels;
+ dup->priv->n_bins = histogram->priv->n_bins;
+ dup->priv->values = g_memdup (histogram->priv->values,
+ sizeof (gdouble) *
+ dup->priv->n_channels *
+ dup->priv->n_bins);
+
+ return dup;
+}
+
+void
+gimp_histogram_calculate (GimpHistogram *histogram,
+ GeglBuffer *buffer,
+ const GeglRectangle *buffer_rect,
+ GeglBuffer *mask,
+ const GeglRectangle *mask_rect)
+{
+ CalculateContext context = {};
+
+ g_return_if_fail (GIMP_IS_HISTOGRAM (histogram));
+ g_return_if_fail (GEGL_IS_BUFFER (buffer));
+ g_return_if_fail (buffer_rect != NULL);
+
+ if (histogram->priv->calculate_async)
+ gimp_async_cancel_and_wait (histogram->priv->calculate_async);
+
+ context.histogram = histogram;
+ context.buffer = buffer;
+ context.buffer_rect = *buffer_rect;
+
+ if (mask)
+ {
+ context.mask = mask;
+
+ if (mask_rect)
+ context.mask_rect = *mask_rect;
+ else
+ context.mask_rect = *gegl_buffer_get_extent (mask);
+ }
+
+ gimp_histogram_calculate_internal (NULL, &context);
+
+ gimp_histogram_set_values (histogram,
+ context.n_components, context.n_bins,
+ context.values);
+}
+
+GimpAsync *
+gimp_histogram_calculate_async (GimpHistogram *histogram,
+ GeglBuffer *buffer,
+ const GeglRectangle *buffer_rect,
+ GeglBuffer *mask,
+ const GeglRectangle *mask_rect)
+{
+ CalculateContext *context;
+ GeglRectangle rect;
+
+ g_return_val_if_fail (GIMP_IS_HISTOGRAM (histogram), NULL);
+ g_return_val_if_fail (GEGL_IS_BUFFER (buffer), NULL);
+ g_return_val_if_fail (buffer_rect != NULL, NULL);
+
+ if (histogram->priv->calculate_async)
+ gimp_async_cancel_and_wait (histogram->priv->calculate_async);
+
+ gegl_rectangle_align_to_buffer (&rect, buffer_rect, buffer,
+ GEGL_RECTANGLE_ALIGNMENT_SUPERSET);
+
+ context = g_slice_new0 (CalculateContext);
+
+ context->histogram = histogram;
+ context->buffer = gegl_buffer_new (&rect,
+ gegl_buffer_get_format (buffer));
+ context->buffer_rect = *buffer_rect;
+
+ gimp_gegl_buffer_copy (buffer, &rect, GEGL_ABYSS_NONE,
+ context->buffer, NULL);
+
+ if (mask)
+ {
+ if (mask_rect)
+ context->mask_rect = *mask_rect;
+ else
+ context->mask_rect = *gegl_buffer_get_extent (mask);
+
+ gegl_rectangle_align_to_buffer (&rect, &context->mask_rect, mask,
+ GEGL_RECTANGLE_ALIGNMENT_SUPERSET);
+
+ context->mask = gegl_buffer_new (&rect, gegl_buffer_get_format (mask));
+
+ gimp_gegl_buffer_copy (mask, &rect, GEGL_ABYSS_NONE,
+ context->mask, NULL);
+ }
+
+ histogram->priv->calculate_async = gimp_parallel_run_async (
+ (GimpRunAsyncFunc) gimp_histogram_calculate_internal,
+ context);
+
+ gimp_async_add_callback (
+ histogram->priv->calculate_async,
+ (GimpAsyncCallback) gimp_histogram_calculate_async_callback,
+ context);
+
+ return histogram->priv->calculate_async;
+}
+
+void
+gimp_histogram_clear_values (GimpHistogram *histogram,
+ gint n_components)
+{
+ g_return_if_fail (GIMP_IS_HISTOGRAM (histogram));
+
+ if (histogram->priv->calculate_async)
+ gimp_async_cancel_and_wait (histogram->priv->calculate_async);
+
+ gimp_histogram_set_values (histogram, n_components, 0, NULL);
+}
+
+
+#define HISTOGRAM_VALUE(c,i) (priv->values[(c) * priv->n_bins + (i)])
+
+
+gdouble
+gimp_histogram_get_maximum (GimpHistogram *histogram,
+ GimpHistogramChannel channel)
+{
+ GimpHistogramPrivate *priv;
+ gdouble max = 0.0;
+ gint x;
+
+ g_return_val_if_fail (GIMP_IS_HISTOGRAM (histogram), 0.0);
+
+ priv = histogram->priv;
+
+ if (! priv->values ||
+ ! gimp_histogram_map_channel (histogram, &channel))
+ {
+ return 0.0;
+ }
+
+ if (channel == GIMP_HISTOGRAM_RGB)
+ {
+ for (x = 0; x < priv->n_bins; x++)
+ {
+ max = MAX (max, HISTOGRAM_VALUE (GIMP_HISTOGRAM_RED, x));
+ max = MAX (max, HISTOGRAM_VALUE (GIMP_HISTOGRAM_GREEN, x));
+ max = MAX (max, HISTOGRAM_VALUE (GIMP_HISTOGRAM_BLUE, x));
+ }
+ }
+ else
+ {
+ for (x = 0; x < priv->n_bins; x++)
+ {
+ max = MAX (max, HISTOGRAM_VALUE (channel, x));
+ }
+ }
+
+ return max;
+}
+
+gdouble
+gimp_histogram_get_value (GimpHistogram *histogram,
+ GimpHistogramChannel channel,
+ gint bin)
+{
+ GimpHistogramPrivate *priv;
+
+ g_return_val_if_fail (GIMP_IS_HISTOGRAM (histogram), 0.0);
+
+ priv = histogram->priv;
+
+ if (! priv->values ||
+ (bin < 0 || bin >= priv->n_bins) ||
+ ! gimp_histogram_map_channel (histogram, &channel))
+ {
+ return 0.0;
+ }
+
+ if (channel == GIMP_HISTOGRAM_RGB)
+ {
+ gdouble min = HISTOGRAM_VALUE (GIMP_HISTOGRAM_RED, bin);
+
+ min = MIN (min, HISTOGRAM_VALUE (GIMP_HISTOGRAM_GREEN, bin));
+
+ return MIN (min, HISTOGRAM_VALUE (GIMP_HISTOGRAM_BLUE, bin));
+ }
+ else
+ {
+ return HISTOGRAM_VALUE (channel, bin);
+ }
+}
+
+gdouble
+gimp_histogram_get_component (GimpHistogram *histogram,
+ gint component,
+ gint bin)
+{
+ g_return_val_if_fail (GIMP_IS_HISTOGRAM (histogram), 0.0);
+
+ if (gimp_histogram_n_components (histogram) > 2)
+ component++;
+
+ return gimp_histogram_get_value (histogram, component, bin);
+}
+
+gint
+gimp_histogram_n_components (GimpHistogram *histogram)
+{
+ g_return_val_if_fail (GIMP_IS_HISTOGRAM (histogram), 0);
+
+ if (histogram->priv->n_channels > 0)
+ return histogram->priv->n_channels - N_DERIVED_CHANNELS;
+ else
+ return 0;
+}
+
+gint
+gimp_histogram_n_bins (GimpHistogram *histogram)
+{
+ g_return_val_if_fail (GIMP_IS_HISTOGRAM (histogram), 0);
+
+ return histogram->priv->n_bins;
+}
+
+gboolean
+gimp_histogram_has_channel (GimpHistogram *histogram,
+ GimpHistogramChannel channel)
+{
+ g_return_val_if_fail (GIMP_IS_HISTOGRAM (histogram), FALSE);
+
+ switch (channel)
+ {
+ case GIMP_HISTOGRAM_VALUE:
+ return TRUE;
+
+ case GIMP_HISTOGRAM_RED:
+ case GIMP_HISTOGRAM_GREEN:
+ case GIMP_HISTOGRAM_BLUE:
+ case GIMP_HISTOGRAM_LUMINANCE:
+ case GIMP_HISTOGRAM_RGB:
+ return gimp_histogram_n_components (histogram) >= 3;
+
+ case GIMP_HISTOGRAM_ALPHA:
+ return gimp_histogram_n_components (histogram) == 2 ||
+ gimp_histogram_n_components (histogram) == 4;
+ }
+
+ g_return_val_if_reached (FALSE);
+}
+
+gdouble
+gimp_histogram_get_count (GimpHistogram *histogram,
+ GimpHistogramChannel channel,
+ gint start,
+ gint end)
+{
+ GimpHistogramPrivate *priv;
+ gint i;
+ gdouble count = 0.0;
+
+ g_return_val_if_fail (GIMP_IS_HISTOGRAM (histogram), 0.0);
+
+ priv = histogram->priv;
+
+ if (! priv->values ||
+ start > end ||
+ ! gimp_histogram_map_channel (histogram, &channel))
+ {
+ return 0.0;
+ }
+
+ if (channel == GIMP_HISTOGRAM_RGB)
+ return (gimp_histogram_get_count (histogram,
+ GIMP_HISTOGRAM_RED, start, end) +
+ gimp_histogram_get_count (histogram,
+ GIMP_HISTOGRAM_GREEN, start, end) +
+ gimp_histogram_get_count (histogram,
+ GIMP_HISTOGRAM_BLUE, start, end));
+
+ start = CLAMP (start, 0, priv->n_bins - 1);
+ end = CLAMP (end, 0, priv->n_bins - 1);
+
+ for (i = start; i <= end; i++)
+ count += HISTOGRAM_VALUE (channel, i);
+
+ return count;
+}
+
+gdouble
+gimp_histogram_get_mean (GimpHistogram *histogram,
+ GimpHistogramChannel channel,
+ gint start,
+ gint end)
+{
+ GimpHistogramPrivate *priv;
+ gint i;
+ gdouble mean = 0.0;
+ gdouble count;
+
+ g_return_val_if_fail (GIMP_IS_HISTOGRAM (histogram), 0.0);
+
+ priv = histogram->priv;
+
+ if (! priv->values ||
+ start > end ||
+ ! gimp_histogram_map_channel (histogram, &channel))
+ {
+ return 0.0;
+ }
+
+ start = CLAMP (start, 0, priv->n_bins - 1);
+ end = CLAMP (end, 0, priv->n_bins - 1);
+
+ if (channel == GIMP_HISTOGRAM_RGB)
+ {
+ for (i = start; i <= end; i++)
+ {
+ gdouble factor = (gdouble) i / (gdouble) (priv->n_bins - 1);
+
+ mean += (factor * HISTOGRAM_VALUE (GIMP_HISTOGRAM_RED, i) +
+ factor * HISTOGRAM_VALUE (GIMP_HISTOGRAM_GREEN, i) +
+ factor * HISTOGRAM_VALUE (GIMP_HISTOGRAM_BLUE, i));
+ }
+ }
+ else
+ {
+ for (i = start; i <= end; i++)
+ {
+ gdouble factor = (gdouble) i / (gdouble) (priv->n_bins - 1);
+
+ mean += factor * HISTOGRAM_VALUE (channel, i);
+ }
+ }
+
+ count = gimp_histogram_get_count (histogram, channel, start, end);
+
+ if (count > 0.0)
+ return mean / count;
+
+ return mean;
+}
+
+gdouble
+gimp_histogram_get_median (GimpHistogram *histogram,
+ GimpHistogramChannel channel,
+ gint start,
+ gint end)
+{
+ GimpHistogramPrivate *priv;
+ gint i;
+ gdouble sum = 0.0;
+ gdouble count;
+
+ g_return_val_if_fail (GIMP_IS_HISTOGRAM (histogram), -1.0);
+
+ priv = histogram->priv;
+
+ if (! priv->values ||
+ start > end ||
+ ! gimp_histogram_map_channel (histogram, &channel))
+ {
+ return 0.0;
+ }
+
+ start = CLAMP (start, 0, priv->n_bins - 1);
+ end = CLAMP (end, 0, priv->n_bins - 1);
+
+ count = gimp_histogram_get_count (histogram, channel, start, end);
+
+ if (channel == GIMP_HISTOGRAM_RGB)
+ {
+ for (i = start; i <= end; i++)
+ {
+ sum += (HISTOGRAM_VALUE (GIMP_HISTOGRAM_RED, i) +
+ HISTOGRAM_VALUE (GIMP_HISTOGRAM_GREEN, i) +
+ HISTOGRAM_VALUE (GIMP_HISTOGRAM_BLUE, i));
+
+ if (sum * 2 > count)
+ return ((gdouble) i / (gdouble) (priv->n_bins - 1));
+ }
+ }
+ else
+ {
+ for (i = start; i <= end; i++)
+ {
+ sum += HISTOGRAM_VALUE (channel, i);
+
+ if (sum * 2 > count)
+ return ((gdouble) i / (gdouble) (priv->n_bins - 1));
+ }
+ }
+
+ return -1.0;
+}
+
+/*
+ * adapted from GNU ocrad 0.14 : page_image_io.cc : otsu_th
+ *
+ * N. Otsu, "A threshold selection method from gray-level histograms,"
+ * IEEE Trans. Systems, Man, and Cybernetics, vol. 9, no. 1, pp. 62-66, 1979.
+ */
+gdouble
+gimp_histogram_get_threshold (GimpHistogram *histogram,
+ GimpHistogramChannel channel,
+ gint start,
+ gint end)
+{
+ GimpHistogramPrivate *priv;
+ gint i;
+ gint maxval;
+ gdouble *hist = NULL;
+ gdouble *chist = NULL;
+ gdouble *cmom = NULL;
+ gdouble hist_max = 0.0;
+ gdouble chist_max = 0.0;
+ gdouble cmom_max = 0.0;
+ gdouble bvar_max = 0.0;
+ gint threshold = 127;
+
+ g_return_val_if_fail (GIMP_IS_HISTOGRAM (histogram), -1);
+
+ priv = histogram->priv;
+
+ if (! priv->values ||
+ start > end ||
+ ! gimp_histogram_map_channel (histogram, &channel))
+ {
+ return 0;
+ }
+
+ start = CLAMP (start, 0, priv->n_bins - 1);
+ end = CLAMP (end, 0, priv->n_bins - 1);
+
+ maxval = end - start;
+
+ hist = g_newa (gdouble, maxval + 1);
+ chist = g_newa (gdouble, maxval + 1);
+ cmom = g_newa (gdouble, maxval + 1);
+
+ if (channel == GIMP_HISTOGRAM_RGB)
+ {
+ for (i = start; i <= end; i++)
+ hist[i - start] = (HISTOGRAM_VALUE (GIMP_HISTOGRAM_RED, i) +
+ HISTOGRAM_VALUE (GIMP_HISTOGRAM_GREEN, i) +
+ HISTOGRAM_VALUE (GIMP_HISTOGRAM_BLUE, i));
+ }
+ else
+ {
+ for (i = start; i <= end; i++)
+ hist[i - start] = HISTOGRAM_VALUE (channel, i);
+ }
+
+ hist_max = hist[0];
+ chist[0] = hist[0];
+ cmom[0] = 0;
+
+ for (i = 1; i <= maxval; i++)
+ {
+ if (hist[i] > hist_max)
+ hist_max = hist[i];
+
+ chist[i] = chist[i-1] + hist[i];
+ cmom[i] = cmom[i-1] + i * hist[i];
+ }
+
+ chist_max = chist[maxval];
+ cmom_max = cmom[maxval];
+ bvar_max = 0;
+
+ for (i = 0; i < maxval; ++i)
+ {
+ if (chist[i] > 0 && chist[i] < chist_max)
+ {
+ gdouble bvar;
+
+ bvar = (gdouble) cmom[i] / chist[i];
+ bvar -= (cmom_max - cmom[i]) / (chist_max - chist[i]);
+ bvar *= bvar;
+ bvar *= chist[i];
+ bvar *= chist_max - chist[i];
+
+ if (bvar > bvar_max)
+ {
+ bvar_max = bvar;
+ threshold = start + i;
+ }
+ }
+ }
+
+ return threshold;
+}
+
+gdouble
+gimp_histogram_get_std_dev (GimpHistogram *histogram,
+ GimpHistogramChannel channel,
+ gint start,
+ gint end)
+{
+ GimpHistogramPrivate *priv;
+ gint i;
+ gdouble dev = 0.0;
+ gdouble count;
+ gdouble mean;
+
+ g_return_val_if_fail (GIMP_IS_HISTOGRAM (histogram), 0.0);
+
+ priv = histogram->priv;
+
+ if (! priv->values ||
+ start > end ||
+ ! gimp_histogram_map_channel (histogram, &channel))
+ {
+ return 0.0;
+ }
+
+ mean = gimp_histogram_get_mean (histogram, channel, start, end);
+ count = gimp_histogram_get_count (histogram, channel, start, end);
+
+ if (count == 0.0)
+ count = 1.0;
+
+ for (i = start; i <= end; i++)
+ {
+ gdouble value;
+
+ if (channel == GIMP_HISTOGRAM_RGB)
+ {
+ value = (HISTOGRAM_VALUE (GIMP_HISTOGRAM_RED, i) +
+ HISTOGRAM_VALUE (GIMP_HISTOGRAM_GREEN, i) +
+ HISTOGRAM_VALUE (GIMP_HISTOGRAM_BLUE, i));
+ }
+ else
+ {
+ value = gimp_histogram_get_value (histogram, channel, i);
+ }
+
+ dev += value * SQR (((gdouble) i / (gdouble) (priv->n_bins - 1)) - mean);
+ }
+
+ return sqrt (dev / count);
+}
+
+
+/* private functions */
+
+static gboolean
+gimp_histogram_map_channel (GimpHistogram *histogram,
+ GimpHistogramChannel *channel)
+{
+ GimpHistogramPrivate *priv = histogram->priv;
+
+ if (*channel == GIMP_HISTOGRAM_RGB)
+ return gimp_histogram_n_components (histogram) >= 3;
+
+ switch (*channel)
+ {
+ case GIMP_HISTOGRAM_ALPHA:
+ if (gimp_histogram_n_components (histogram) == 2)
+ *channel = 1;
+ break;
+
+ case GIMP_HISTOGRAM_LUMINANCE:
+ *channel = gimp_histogram_n_components (histogram) + 1;
+ break;
+
+ default:
+ break;
+ }
+
+ return *channel < priv->n_channels;
+}
+
+static void
+gimp_histogram_set_values (GimpHistogram *histogram,
+ gint n_components,
+ gint n_bins,
+ gdouble *values)
+{
+ GimpHistogramPrivate *priv = histogram->priv;
+ gint n_channels = n_components;
+ gboolean notify_n_components = FALSE;
+ gboolean notify_n_bins = FALSE;
+
+ if (n_channels > 0)
+ n_channels += N_DERIVED_CHANNELS;
+
+ if (n_channels != priv->n_channels)
+ {
+ priv->n_channels = n_channels;
+
+ notify_n_components = TRUE;
+ }
+
+ if (n_bins != priv->n_bins)
+ {
+ priv->n_bins = n_bins;
+
+ notify_n_bins = TRUE;
+ }
+
+ if (values != priv->values)
+ {
+ if (priv->values)
+ g_free (priv->values);
+
+ priv->values = values;
+ }
+
+ if (notify_n_components)
+ g_object_notify (G_OBJECT (histogram), "n-components");
+
+ if (notify_n_bins)
+ g_object_notify (G_OBJECT (histogram), "n-bins");
+
+ g_object_notify (G_OBJECT (histogram), "values");
+}
+
+static void
+gimp_histogram_calculate_internal (GimpAsync *async,
+ CalculateContext *context)
+{
+ CalculateData data;
+ GimpHistogramPrivate *priv;
+ const Babl *format;
+
+ priv = context->histogram->priv;
+
+ format = gegl_buffer_get_format (context->buffer);
+
+ if (babl_format_get_type (format, 0) == babl_type ("u8"))
+ context->n_bins = 256;
+ else
+ context->n_bins = 1024;
+
+ if (babl_format_is_palette (format))
+ {
+ if (babl_format_has_alpha (format))
+ {
+ if (priv->linear)
+ format = babl_format ("RGB float");
+ else
+ format = babl_format ("R'G'B' float");
+ }
+ else
+ {
+ if (priv->linear)
+ format = babl_format ("RGBA float");
+ else
+ format = babl_format ("R'G'B'A float");
+ }
+ }
+ else
+ {
+ const Babl *model = babl_format_get_model (format);
+
+ if (model == babl_model ("Y") ||
+ model == babl_model ("Y'"))
+ {
+ if (priv->linear)
+ format = babl_format ("Y float");
+ else
+ format = babl_format ("Y' float");
+ }
+ else if (model == babl_model ("YA") ||
+ model == babl_model ("Y'A"))
+ {
+ if (priv->linear)
+ format = babl_format ("YA float");
+ else
+ format = babl_format ("Y'A float");
+ }
+ else if (model == babl_model ("RGB") ||
+ model == babl_model ("R'G'B'"))
+ {
+ if (priv->linear)
+ format = babl_format ("RGB float");
+ else
+ format = babl_format ("R'G'B' float");
+ }
+ else if (model == babl_model ("RGBA") ||
+ model == babl_model ("R'G'B'A"))
+ {
+ if (priv->linear)
+ format = babl_format ("RGBA float");
+ else
+ format = babl_format ("R'G'B'A float");
+ }
+ else
+ {
+ if (async)
+ gimp_async_abort (async);
+
+ g_return_if_reached ();
+ }
+ }
+
+ context->n_components = babl_format_get_n_components (format);
+
+ data.async = async;
+ data.context = context;
+ data.format = format;
+ data.values_list = NULL;
+
+ gegl_parallel_distribute_area (
+ &context->buffer_rect, PIXELS_PER_THREAD, GEGL_SPLIT_STRATEGY_AUTO,
+ (GeglParallelDistributeAreaFunc) gimp_histogram_calculate_area,
+ &data);
+
+ if (! async || ! gimp_async_is_canceled (async))
+ {
+ gdouble *total_values = NULL;
+ gint n_values = (context->n_components + N_DERIVED_CHANNELS) *
+ context->n_bins;
+ GSList *iter;
+
+ for (iter = data.values_list; iter; iter = g_slist_next (iter))
+ {
+ gdouble *values = iter->data;
+
+ if (! total_values)
+ {
+ total_values = values;
+ }
+ else
+ {
+ gint i;
+
+ for (i = 0; i < n_values; i++)
+ total_values[i] += values[i];
+
+ g_free (values);
+ }
+ }
+
+ g_slist_free (data.values_list);
+
+ context->values = total_values;
+
+ if (async)
+ gimp_async_finish (async, NULL);
+ }
+ else
+ {
+ g_slist_free_full (data.values_list, g_free);
+
+ if (async)
+ gimp_async_abort (async);
+ }
+}
+
+static void
+gimp_histogram_calculate_area (const GeglRectangle *area,
+ CalculateData *data)
+{
+ GimpAsync *async;
+ CalculateContext *context;
+ GeglBufferIterator *iter;
+ gdouble *values;
+ gint n_components;
+ gint n_bins;
+ gfloat n_bins_1f;
+ gfloat temp;
+
+ async = data->async;
+ context = data->context;
+
+ n_bins = context->n_bins;
+ n_components = context->n_components;
+
+ values = g_new0 (gdouble, (n_components + N_DERIVED_CHANNELS) * n_bins);
+ gimp_atomic_slist_push_head (&data->values_list, values);
+
+ iter = gegl_buffer_iterator_new (context->buffer, area, 0,
+ data->format,
+ GEGL_ACCESS_READ, GEGL_ABYSS_NONE, 2);
+
+ if (context->mask)
+ {
+ GeglRectangle mask_area = *area;
+
+ mask_area.x += context->mask_rect.x - context->buffer_rect.x;
+ mask_area.y += context->mask_rect.y - context->buffer_rect.y;
+
+ gegl_buffer_iterator_add (iter, context->mask, &mask_area, 0,
+ babl_format ("Y float"),
+ GEGL_ACCESS_READ, GEGL_ABYSS_NONE);
+ }
+
+ n_bins_1f = n_bins - 1;
+
+#define VALUE(c,i) (*(temp = (i) * n_bins_1f, \
+ &values[(c) * n_bins + \
+ SIGNED_ROUND (SAFE_CLAMP (temp, \
+ 0.0f, \
+ n_bins_1f))]))
+
+#define CHECK_CANCELED(length) \
+ G_STMT_START \
+ { \
+ if ((length) % 128 == 0 && async && gimp_async_is_canceled (async)) \
+ { \
+ gegl_buffer_iterator_stop (iter); \
+ \
+ return; \
+ } \
+ } \
+ G_STMT_END
+
+ while (gegl_buffer_iterator_next (iter))
+ {
+ const gfloat *data = iter->items[0].data;
+ gint length = iter->length;
+ gfloat max;
+ gfloat luminance;
+
+ CHECK_CANCELED (0);
+
+ if (context->mask)
+ {
+ const gfloat *mask_data = iter->items[1].data;
+
+ switch (n_components)
+ {
+ case 1:
+ while (length--)
+ {
+ const gdouble masked = *mask_data;
+
+ VALUE (0, data[0]) += masked;
+
+ data += n_components;
+ mask_data += 1;
+
+ CHECK_CANCELED (length);
+ }
+ break;
+
+ case 2:
+ while (length--)
+ {
+ const gdouble masked = *mask_data;
+ const gdouble weight = data[1];
+
+ VALUE (0, data[0]) += weight * masked;
+ VALUE (1, data[1]) += masked;
+
+ data += n_components;
+ mask_data += 1;
+
+ CHECK_CANCELED (length);
+ }
+ break;
+
+ case 3: /* calculate separate value values */
+ while (length--)
+ {
+ const gdouble masked = *mask_data;
+
+ VALUE (1, data[0]) += masked;
+ VALUE (2, data[1]) += masked;
+ VALUE (3, data[2]) += masked;
+
+ max = MAX (data[0], data[1]);
+ max = MAX (data[2], max);
+ VALUE (0, max) += masked;
+
+ luminance = GIMP_RGB_LUMINANCE (data[0], data[1], data[2]);
+ VALUE (4, luminance) += masked;
+
+ data += n_components;
+ mask_data += 1;
+
+ CHECK_CANCELED (length);
+ }
+ break;
+
+ case 4: /* calculate separate value values */
+ while (length--)
+ {
+ const gdouble masked = *mask_data;
+ const gdouble weight = data[3];
+
+ VALUE (1, data[0]) += weight * masked;
+ VALUE (2, data[1]) += weight * masked;
+ VALUE (3, data[2]) += weight * masked;
+ VALUE (4, data[3]) += masked;
+
+ max = MAX (data[0], data[1]);
+ max = MAX (data[2], max);
+ VALUE (0, max) += weight * masked;
+
+ luminance = GIMP_RGB_LUMINANCE (data[0], data[1], data[2]);
+ VALUE (5, luminance) += weight * masked;
+
+ data += n_components;
+ mask_data += 1;
+
+ CHECK_CANCELED (length);
+ }
+ break;
+ }
+ }
+ else /* no mask */
+ {
+ switch (n_components)
+ {
+ case 1:
+ while (length--)
+ {
+ VALUE (0, data[0]) += 1.0;
+
+ data += n_components;
+
+ CHECK_CANCELED (length);
+ }
+ break;
+
+ case 2:
+ while (length--)
+ {
+ const gdouble weight = data[1];
+
+ VALUE (0, data[0]) += weight;
+ VALUE (1, data[1]) += 1.0;
+
+ data += n_components;
+
+ CHECK_CANCELED (length);
+ }
+ break;
+
+ case 3: /* calculate separate value values */
+ while (length--)
+ {
+ VALUE (1, data[0]) += 1.0;
+ VALUE (2, data[1]) += 1.0;
+ VALUE (3, data[2]) += 1.0;
+
+ max = MAX (data[0], data[1]);
+ max = MAX (data[2], max);
+ VALUE (0, max) += 1.0;
+
+ luminance = GIMP_RGB_LUMINANCE (data[0], data[1], data[2]);
+ VALUE (4, luminance) += 1.0;
+
+ data += n_components;
+
+ CHECK_CANCELED (length);
+ }
+ break;
+
+ case 4: /* calculate separate value values */
+ while (length--)
+ {
+ const gdouble weight = data[3];
+
+ VALUE (1, data[0]) += weight;
+ VALUE (2, data[1]) += weight;
+ VALUE (3, data[2]) += weight;
+ VALUE (4, data[3]) += 1.0;
+
+ max = MAX (data[0], data[1]);
+ max = MAX (data[2], max);
+ VALUE (0, max) += weight;
+
+ luminance = GIMP_RGB_LUMINANCE (data[0], data[1], data[2]);
+ VALUE (5, luminance) += weight;
+
+ data += n_components;
+
+ CHECK_CANCELED (length);
+ }
+ break;
+ }
+ }
+ }
+
+#undef VALUE
+#undef CHECK_CANCELED
+}
+
+static void
+gimp_histogram_calculate_async_callback (GimpAsync *async,
+ CalculateContext *context)
+{
+ context->histogram->priv->calculate_async = NULL;
+
+ if (gimp_async_is_finished (async))
+ {
+ gimp_histogram_set_values (context->histogram,
+ context->n_components, context->n_bins,
+ context->values);
+ }
+
+ g_object_unref (context->buffer);
+ if (context->mask)
+ g_object_unref (context->mask);
+
+ g_slice_free (CalculateContext, context);
+}