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gimp/app/core/gimpimage-merge.c

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/* GIMP - The GNU Image Manipulation Program
* Copyright (C) 1995 Spencer Kimball and Peter Mattis
*
* 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 "libgimpbase/gimpbase.h"
#include "core-types.h"
#include "gegl/gimp-babl-compat.h"
#include "gegl/gimp-gegl-apply-operation.h"
#include "gegl/gimp-gegl-nodes.h"
#include "gegl/gimp-gegl-utils.h"
#include "vectors/gimppath.h"
#include "gimp.h"
#include "gimpcontext.h"
#include "gimpdrawable-filters.h"
#include "gimperror.h"
#include "gimpgrouplayer.h"
#include "gimpimage.h"
#include "gimpimage-merge.h"
#include "gimpimage-undo.h"
#include "gimpitemstack.h"
#include "gimplayer-floating-selection.h"
#include "gimplayer-new.h"
#include "gimplayermask.h"
#include "gimpparasitelist.h"
#include "gimppickable.h"
#include "gimpprogress.h"
#include "gimpprojectable.h"
#include "gimpundostack.h"
#include "gimp-intl.h"
static GimpLayer * gimp_image_merge_layers (GimpImage *image,
GimpContainer *container,
GSList *merge_list,
GimpContext *context,
GimpMergeType merge_type,
const gchar *undo_desc,
GimpProgress *progress);
/* public functions */
GList *
gimp_image_merge_visible_layers (GimpImage *image,
GimpContext *context,
GimpMergeType merge_type,
gboolean merge_active_group,
gboolean discard_invisible,
GimpProgress *progress)
{
const gchar *undo_desc = C_("undo-type", "Merge Visible Layers");
GList *containers = NULL;
GList *new_layers = NULL;
GList *iter;
GList *iter2;
g_return_val_if_fail (GIMP_IS_IMAGE (image), NULL);
g_return_val_if_fail (GIMP_IS_CONTEXT (context), NULL);
g_return_val_if_fail (progress == NULL || GIMP_IS_PROGRESS (progress), NULL);
if (merge_active_group)
{
GList *selected_layers = gimp_image_get_selected_layers (image);
/* if the active layer is the floating selection, get the
* underlying drawable, but only if it is a layer
*/
if (g_list_length (selected_layers) == 1 && gimp_layer_is_floating_sel (selected_layers->data))
{
GimpDrawable *fs_drawable;
fs_drawable = gimp_layer_get_floating_sel_drawable (selected_layers->data);
if (GIMP_IS_LAYER (fs_drawable))
containers = g_list_prepend (containers,
gimp_item_get_container (GIMP_ITEM (fs_drawable)));
}
else
{
for (iter = selected_layers; iter; iter = iter->next)
if (! gimp_item_get_parent (iter->data))
break;
/* No need to list selected groups if any selected layer is
* top-level.
*/
if (iter == NULL)
{
for (iter = selected_layers; iter; iter = iter->next)
{
for (iter2 = selected_layers; iter2; iter2 = iter2->next)
{
/* Only retain a selected layer's container if no
* other selected layers are its parents.
*/
if (iter->data != iter2->data &&
gimp_viewable_is_ancestor (iter2->data, iter->data))
break;
}
if (iter2 == NULL &&
! g_list_find (containers, gimp_item_get_container (GIMP_ITEM (iter->data))))
containers = g_list_prepend (containers,
gimp_item_get_container (GIMP_ITEM (iter->data)));
}
}
}
}
if (! containers)
containers = g_list_prepend (NULL, gimp_image_get_layers (image));
gimp_set_busy (image->gimp);
gimp_image_undo_group_start (image,
GIMP_UNDO_GROUP_IMAGE_LAYERS_MERGE,
undo_desc);
for (iter = containers; iter; iter = iter->next)
{
GimpContainer *container = iter->data;
GSList *merge_list = NULL;
GSList *invisible_list = NULL;
for (iter2 = gimp_item_stack_get_item_iter (GIMP_ITEM_STACK (container));
iter2;
iter2 = g_list_next (iter2))
{
GimpLayer *layer = iter2->data;
if (gimp_layer_is_floating_sel (layer))
continue;
if (gimp_item_get_visible (GIMP_ITEM (layer)))
{
merge_list = g_slist_append (merge_list, layer);
}
else if (discard_invisible)
{
invisible_list = g_slist_append (invisible_list, layer);
}
}
if (merge_list)
{
GimpLayer *layer;
/* if there's a floating selection, anchor it */
if (gimp_image_get_floating_selection (image))
floating_sel_anchor (gimp_image_get_floating_selection (image));
layer = gimp_image_merge_layers (image,
container,
merge_list, context, merge_type,
undo_desc, progress);
g_slist_free (merge_list);
if (invisible_list)
{
GSList *list;
for (list = invisible_list; list; list = g_slist_next (list))
gimp_image_remove_layer (image, list->data, TRUE, NULL);
g_slist_free (invisible_list);
}
new_layers = g_list_prepend (new_layers, layer);
}
}
gimp_image_set_selected_layers (image, new_layers);
gimp_image_undo_group_end (image);
gimp_unset_busy (image->gimp);
g_list_free (new_layers);
g_list_free (containers);
return gimp_image_get_selected_layers (image);
}
GimpLayer *
gimp_image_flatten (GimpImage *image,
GimpContext *context,
GimpProgress *progress,
GError **error)
{
GList *list;
GSList *merge_list = NULL;
GimpLayer *layer;
g_return_val_if_fail (GIMP_IS_IMAGE (image), NULL);
g_return_val_if_fail (GIMP_IS_CONTEXT (context), NULL);
g_return_val_if_fail (progress == NULL || GIMP_IS_PROGRESS (progress), NULL);
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
for (list = gimp_image_get_layer_iter (image);
list;
list = g_list_next (list))
{
layer = list->data;
if (gimp_layer_is_floating_sel (layer))
continue;
if (gimp_item_get_visible (GIMP_ITEM (layer)))
merge_list = g_slist_append (merge_list, layer);
}
if (merge_list)
{
const gchar *undo_desc = C_("undo-type", "Flatten Image");
gimp_set_busy (image->gimp);
gimp_image_undo_group_start (image,
GIMP_UNDO_GROUP_IMAGE_LAYERS_MERGE,
undo_desc);
/* if there's a floating selection, anchor it */
if (gimp_image_get_floating_selection (image))
floating_sel_anchor (gimp_image_get_floating_selection (image));
layer = gimp_image_merge_layers (image,
gimp_image_get_layers (image),
merge_list, context,
GIMP_FLATTEN_IMAGE,
undo_desc, progress);
g_slist_free (merge_list);
gimp_image_alpha_changed (image);
gimp_image_undo_group_end (image);
gimp_unset_busy (image->gimp);
return layer;
}
g_set_error_literal (error, GIMP_ERROR, GIMP_FAILED,
_("Cannot flatten an image without any visible layer."));
return NULL;
}
GList *
gimp_image_merge_down (GimpImage *image,
GList *layers,
GimpContext *context,
GimpMergeType merge_type,
GimpProgress *progress,
GError **error)
{
GList *merged_layers = NULL;
GList *merge_lists = NULL;
GSList *merge_list = NULL;
GimpLayer *layer;
GList *list;
const gchar *undo_desc;
g_return_val_if_fail (GIMP_IS_IMAGE (image), NULL);
g_return_val_if_fail (GIMP_IS_CONTEXT (context), NULL);
g_return_val_if_fail (progress == NULL || GIMP_IS_PROGRESS (progress), NULL);
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
layers = g_list_copy (layers);
while ((list = layers))
{
GList *list2;
g_return_val_if_fail (GIMP_IS_LAYER (list->data), NULL);
g_return_val_if_fail (gimp_item_is_attached (GIMP_ITEM (list->data)), NULL);
if (gimp_layer_is_floating_sel (list->data))
{
g_set_error_literal (error, GIMP_ERROR, GIMP_FAILED,
_("Cannot merge down a floating selection."));
g_list_free (layers);
g_list_free_full (merge_lists, (GDestroyNotify) g_slist_free);
return NULL;
}
if (! gimp_item_get_visible (GIMP_ITEM (list->data)))
{
g_set_error_literal (error, GIMP_ERROR, GIMP_FAILED,
_("Cannot merge down an invisible layer."));
g_list_free (layers);
g_list_free_full (merge_lists, (GDestroyNotify) g_slist_free);
return NULL;
}
for (list2 = gimp_item_get_container_iter (GIMP_ITEM (list->data));
list2;
list2 = g_list_next (list2))
{
if (list2->data == list->data)
break;
}
layer = NULL;
for (list2 = g_list_next (list2);
list2;
list2 = g_list_next (list2))
{
layer = list2->data;
if (gimp_item_get_visible (GIMP_ITEM (layer)))
{
if (gimp_viewable_get_children (GIMP_VIEWABLE (layer)))
{
g_set_error_literal (error, GIMP_ERROR, GIMP_FAILED,
_("Cannot merge down to a layer group."));
g_list_free (layers);
g_list_free_full (merge_lists, (GDestroyNotify) g_slist_free);
return NULL;
}
if (gimp_item_is_content_locked (GIMP_ITEM (layer), NULL))
{
g_set_error_literal (error, GIMP_ERROR, GIMP_FAILED,
_("The layer to merge down to is locked."));
g_list_free (layers);
g_list_free_full (merge_lists, (GDestroyNotify) g_slist_free);
return NULL;
}
break;
}
layer = NULL;
}
if (! layer)
{
g_set_error_literal (error, GIMP_ERROR, GIMP_FAILED,
_("There is no visible layer to merge down to."));
g_list_free (layers);
g_list_free_full (merge_lists, (GDestroyNotify) g_slist_free);
return NULL;
}
merge_list = g_slist_append (merge_list, list->data);
layers = g_list_delete_link (layers, layers);
if ((list = g_list_find (layers, layer)))
{
/* The next item is itself in the merge down list. Continue
* filling the same merge list instead of starting a new one.
*/
layers = g_list_delete_link (layers, list);
layers = g_list_prepend (layers, layer);
continue;
}
merge_list = g_slist_append (merge_list, layer);
merge_lists = g_list_prepend (merge_lists, merge_list);
merge_list = NULL;
}
undo_desc = C_("undo-type", "Merge Down");
gimp_set_busy (image->gimp);
gimp_image_undo_group_start (image,
GIMP_UNDO_GROUP_IMAGE_LAYERS_MERGE,
undo_desc);
for (list = merge_lists; list; list = list->next)
{
merge_list = list->data;
layer = gimp_image_merge_layers (image,
gimp_item_get_container (merge_list->data),
merge_list, context, merge_type,
undo_desc, progress);
merged_layers = g_list_prepend (merged_layers, layer);
}
g_list_free_full (merge_lists, (GDestroyNotify) g_slist_free);
gimp_image_undo_group_end (image);
gimp_unset_busy (image->gimp);
return merged_layers;
}
GimpLayer *
gimp_image_merge_group_layer (GimpImage *image,
GimpGroupLayer *group)
{
GimpLayer *parent;
GimpLayer *layer;
gint index;
g_return_val_if_fail (GIMP_IS_IMAGE (image), NULL);
g_return_val_if_fail (GIMP_IS_GROUP_LAYER (group), NULL);
g_return_val_if_fail (gimp_item_is_attached (GIMP_ITEM (group)), NULL);
g_return_val_if_fail (gimp_item_get_image (GIMP_ITEM (group)) == image, NULL);
gimp_image_undo_group_start (image, GIMP_UNDO_GROUP_IMAGE_LAYERS_MERGE,
C_("undo-type", "Merge Layer Group"));
parent = gimp_layer_get_parent (GIMP_LAYER (group));
index = gimp_item_get_index (GIMP_ITEM (group));
/* if this is a pass-through group, change its mode to NORMAL *before*
* duplicating it, since PASS_THROUGH mode is invalid for regular layers.
* see bug #793714.
*/
if (gimp_layer_get_mode (GIMP_LAYER (group)) == GIMP_LAYER_MODE_PASS_THROUGH)
{
GimpLayerColorSpace blend_space;
GimpLayerColorSpace composite_space;
GimpLayerCompositeMode composite_mode;
/* keep the group's current blend space, composite space, and composite
* mode.
*/
blend_space = gimp_layer_get_blend_space (GIMP_LAYER (group));
composite_space = gimp_layer_get_composite_space (GIMP_LAYER (group));
composite_mode = gimp_layer_get_composite_mode (GIMP_LAYER (group));
gimp_layer_set_mode (GIMP_LAYER (group), GIMP_LAYER_MODE_NORMAL, TRUE);
gimp_layer_set_blend_space (GIMP_LAYER (group), blend_space, TRUE);
gimp_layer_set_composite_space (GIMP_LAYER (group), composite_space, TRUE);
gimp_layer_set_composite_mode (GIMP_LAYER (group), composite_mode, TRUE);
}
/* Merge down filter effects */
gimp_drawable_merge_filters (GIMP_DRAWABLE (group));
gimp_drawable_clear_filters (GIMP_DRAWABLE (group));
layer = GIMP_LAYER (gimp_item_duplicate (GIMP_ITEM (group),
GIMP_TYPE_LAYER));
gimp_object_set_name (GIMP_OBJECT (layer), gimp_object_get_name (group));
gimp_image_remove_layer (image, GIMP_LAYER (group), TRUE, NULL);
gimp_image_add_layer (image, layer, parent, index, TRUE);
gimp_image_undo_group_end (image);
return layer;
}
/* merging paths */
GimpPath *
gimp_image_merge_visible_paths (GimpImage *image,
GError **error)
{
GList *list;
GList *merge_list = NULL;
GimpPath *path;
g_return_val_if_fail (GIMP_IS_IMAGE (image), NULL);
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
for (list = gimp_image_get_path_iter (image);
list;
list = g_list_next (list))
{
path = list->data;
if (gimp_item_get_visible (GIMP_ITEM (path)))
merge_list = g_list_prepend (merge_list, path);
}
merge_list = g_list_reverse (merge_list);
if (merge_list && merge_list->next)
{
GimpPath *target_path;
gchar *name;
gint pos;
gimp_set_busy (image->gimp);
gimp_image_undo_group_start (image, GIMP_UNDO_GROUP_IMAGE_PATHS_MERGE,
C_("undo-type", "Merge Visible Paths"));
path = GIMP_PATH (merge_list->data);
name = g_strdup (gimp_object_get_name (path));
pos = gimp_item_get_index (GIMP_ITEM (path));
target_path = GIMP_PATH (gimp_item_duplicate (GIMP_ITEM (path),
GIMP_TYPE_PATH));
gimp_image_remove_path (image, path, TRUE, NULL);
for (list = g_list_next (merge_list);
list;
list = g_list_next (list))
{
path = list->data;
gimp_path_add_strokes (path, target_path);
gimp_image_remove_path (image, path, TRUE, NULL);
}
gimp_object_take_name (GIMP_OBJECT (target_path), name);
g_list_free (merge_list);
/* FIXME tree */
gimp_image_add_path (image, target_path, NULL, pos, TRUE);
gimp_unset_busy (image->gimp);
gimp_image_undo_group_end (image);
return target_path;
}
else
{
g_set_error_literal (error, GIMP_ERROR, GIMP_FAILED,
_("Not enough visible paths for a merge. "
"There must be at least two."));
return NULL;
}
}
/* private functions */
static GimpLayer *
gimp_image_merge_layers (GimpImage *image,
GimpContainer *container,
GSList *merge_list,
GimpContext *context,
GimpMergeType merge_type,
const gchar *undo_desc,
GimpProgress *progress)
{
GimpLayer *parent;
gint x1, y1;
gint x2, y2;
GSList *layers;
GimpLayer *layer;
GimpLayer *top_layer;
GimpLayer *bottom_layer;
GimpLayer *merge_layer;
gint position;
GeglNode *node;
GeglNode *source_node;
GeglNode *flatten_node;
GeglNode *offset_node;
GeglNode *last_node;
GeglNode *last_node_source;
GimpParasiteList *parasites;
g_return_val_if_fail (GIMP_IS_IMAGE (image), NULL);
g_return_val_if_fail (GIMP_IS_CONTEXT (context), NULL);
g_return_val_if_fail (progress == NULL || GIMP_IS_PROGRESS (progress), NULL);
top_layer = merge_list->data;
parent = gimp_layer_get_parent (top_layer);
/* Make sure the image's graph is constructed, so that top-level layers have
* a parent node.
*/
(void) gimp_projectable_get_graph (GIMP_PROJECTABLE (image));
/* Make sure the parent's graph is constructed, so that the top layer has a
* parent node, even if it is the child of a group layer (in particular, of
* an invisible group layer, whose graph may not have been constructed as a
* result of the above call. see issue #2095.)
*/
if (parent)
(void) gimp_filter_get_node (GIMP_FILTER (parent));
/* Build our graph inside the top-layer's parent node */
source_node = gimp_filter_get_node (GIMP_FILTER (top_layer));
node = gegl_node_get_parent (source_node);
g_return_val_if_fail (node, NULL);
/* Get the layer extents */
x1 = y1 = 0;
x2 = y2 = 0;
for (layers = merge_list; layers; layers = g_slist_next (layers))
{
gint off_x, off_y;
layer = layers->data;
/* Merge down filter effects so they can be restored on undo */
gimp_drawable_merge_filters (GIMP_DRAWABLE (layer));
gimp_drawable_clear_filters (GIMP_DRAWABLE (layer));
gimp_item_get_offset (GIMP_ITEM (layer), &off_x, &off_y);
switch (merge_type)
{
case GIMP_EXPAND_AS_NECESSARY:
case GIMP_CLIP_TO_IMAGE:
if (layers == merge_list)
{
x1 = off_x;
y1 = off_y;
x2 = off_x + gimp_item_get_width (GIMP_ITEM (layer));
y2 = off_y + gimp_item_get_height (GIMP_ITEM (layer));
}
else
{
if (off_x < x1)
x1 = off_x;
if (off_y < y1)
y1 = off_y;
if ((off_x + gimp_item_get_width (GIMP_ITEM (layer))) > x2)
x2 = (off_x + gimp_item_get_width (GIMP_ITEM (layer)));
if ((off_y + gimp_item_get_height (GIMP_ITEM (layer))) > y2)
y2 = (off_y + gimp_item_get_height (GIMP_ITEM (layer)));
}
if (merge_type == GIMP_CLIP_TO_IMAGE)
{
x1 = CLAMP (x1, 0, gimp_image_get_width (image));
y1 = CLAMP (y1, 0, gimp_image_get_height (image));
x2 = CLAMP (x2, 0, gimp_image_get_width (image));
y2 = CLAMP (y2, 0, gimp_image_get_height (image));
}
break;
case GIMP_CLIP_TO_BOTTOM_LAYER:
if (layers->next == NULL)
{
x1 = off_x;
y1 = off_y;
x2 = off_x + gimp_item_get_width (GIMP_ITEM (layer));
y2 = off_y + gimp_item_get_height (GIMP_ITEM (layer));
}
break;
case GIMP_FLATTEN_IMAGE:
if (layers->next == NULL)
{
x1 = 0;
y1 = 0;
x2 = gimp_image_get_width (image);
y2 = gimp_image_get_height (image);
}
break;
}
}
if ((x2 - x1) == 0 || (y2 - y1) == 0)
return NULL;
bottom_layer = layer;
flatten_node = NULL;
if (merge_type == GIMP_FLATTEN_IMAGE ||
(gimp_drawable_is_indexed (GIMP_DRAWABLE (layer)) &&
! gimp_drawable_has_alpha (GIMP_DRAWABLE (layer))))
{
merge_layer = gimp_layer_new (image, (x2 - x1), (y2 - y1),
gimp_image_get_layer_format (image, FALSE),
gimp_object_get_name (bottom_layer),
GIMP_OPACITY_OPAQUE,
gimp_image_get_default_new_layer_mode (image));
if (! merge_layer)
{
g_warning ("%s: could not allocate merge layer", G_STRFUNC);
return NULL;
}
/* get the background for compositing */
flatten_node = gimp_gegl_create_flatten_node
(gimp_context_get_background (context),
gimp_layer_get_real_composite_space (bottom_layer));
}
else
{
/* The final merged layer inherits the name of the bottom most layer
* and the resulting layer has an alpha channel whether or not the
* original did. Opacity is set to 100% and the MODE is set to normal.
*/
merge_layer =
gimp_layer_new (image, (x2 - x1), (y2 - y1),
gimp_drawable_get_format_with_alpha (GIMP_DRAWABLE (bottom_layer)),
gimp_object_get_name (bottom_layer),
GIMP_OPACITY_OPAQUE,
gimp_image_get_default_new_layer_mode (image));
if (! merge_layer)
{
g_warning ("%s: could not allocate merge layer", G_STRFUNC);
return NULL;
}
}
if (merge_type == GIMP_FLATTEN_IMAGE)
{
position = 0;
}
else
{
/* Find the index in the layer list of the bottom layer--we need this
* in order to add the final, merged layer to the layer list correctly
*/
position =
gimp_container_get_n_children (container) -
gimp_container_get_child_index (container, GIMP_OBJECT (bottom_layer));
}
gimp_item_set_offset (GIMP_ITEM (merge_layer), x1, y1);
offset_node = gegl_node_new_child (node,
"operation", "gegl:translate",
"x", (gdouble) -x1,
"y", (gdouble) -y1,
NULL);
if (flatten_node)
{
gegl_node_add_child (node, flatten_node);
g_object_unref (flatten_node);
gegl_node_link_many (source_node, flatten_node, offset_node, NULL);
}
else
{
gegl_node_link_many (source_node, offset_node, NULL);
}
/* Disconnect the bottom-layer node's input */
last_node = gimp_filter_get_node (GIMP_FILTER (bottom_layer));
last_node_source = gegl_node_get_producer (last_node, "input", NULL);
gegl_node_disconnect (last_node, "input");
/* Render the graph into the merge layer */
gimp_gegl_apply_operation (NULL, progress, undo_desc, offset_node,
gimp_drawable_get_buffer (
GIMP_DRAWABLE (merge_layer)),
NULL, FALSE);
/* Reconnect the bottom-layer node's input */
if (last_node_source)
gegl_node_link (last_node_source, last_node);
/* Clean up the graph */
gegl_node_remove_child (node, offset_node);
if (flatten_node)
gegl_node_remove_child (node, flatten_node);
/* Copy the tattoo and parasites of the bottom layer to the new layer */
gimp_item_set_tattoo (GIMP_ITEM (merge_layer),
gimp_item_get_tattoo (GIMP_ITEM (bottom_layer)));
parasites = gimp_item_get_parasites (GIMP_ITEM (bottom_layer));
parasites = gimp_parasite_list_copy (parasites);
gimp_item_set_parasites (GIMP_ITEM (merge_layer), parasites);
g_object_unref (parasites);
/* Remove the merged layers from the image */
for (layers = merge_list; layers; layers = g_slist_next (layers))
gimp_image_remove_layer (image, layers->data, TRUE, NULL);
gimp_item_set_visible (GIMP_ITEM (merge_layer), TRUE, FALSE);
/* if the type is flatten, remove all the remaining layers */
if (merge_type == GIMP_FLATTEN_IMAGE)
{
GList *list = gimp_image_get_layer_iter (image);
while (list)
{
layer = list->data;
list = g_list_next (list);
gimp_image_remove_layer (image, layer, TRUE, NULL);
}
gimp_image_add_layer (image, merge_layer, parent,
position, TRUE);
}
else
{
/* Add the layer to the image */
gimp_image_add_layer (image, merge_layer, parent,
gimp_container_get_n_children (container) -
position + 1,
TRUE);
}
gimp_drawable_update (GIMP_DRAWABLE (merge_layer), 0, 0, -1, -1);
return merge_layer;
}
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