[gegl/soc-2013-opecl-ops] operations: Add gegl:webp-load

[Carlos Zubieta <czubieta src gnome org>]

commit 50505e82a5683d2ffa77f58328d637ce652ccee6
Author: Michael Henning <drawoc darkrefraction com>
Date:   Wed Jul 24 14:04:07 2013 -0400

    operations: Add gegl:webp-load

 configure.ac                    |   20 ++++++
 operations/external/Makefile.am |    7 ++
 operations/external/webp-load.c |  141 +++++++++++++++++++++++++++++++++++++++
 po/POTFILES.in                  |    1 +
 4 files changed, 169 insertions(+), 0 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index ad0934e..3a50958 100644
--- a/configure.ac
+++ b/configure.ac
@@ -54,6 +54,7 @@ m4_define([pango_required_version], [0.0.0])
 m4_define([pangocairo_required_version], [0.0.0])
 m4_define([png_required_version], [0.0.0])
 m4_define([sdl_required_version], [0.0.0])
+m4_define([webp_required_version], [0.0.0])
 m4_define([poly2tri-c_required_version], [0.0.0])
 
 AC_INIT(gegl, gegl_major_version.gegl_minor_version.gegl_micro_version)
@@ -1007,6 +1008,24 @@ AM_CONDITIONAL(HAVE_UMFPACK, test "x$have_umfpack" = "xyes")
 AC_SUBST(UMFPACK_CFLAGS)
 AC_SUBST(UMFPACK_LIBS)
 
+################
+# Check for webp
+################
+
+AC_ARG_WITH(webp, [  --without-webp          build without webp support])
+
+have_webp="no"
+if test "x$with_webp" != "xno"; then
+  PKG_CHECK_MODULES(WEBP, libwebp >= webp_required_version,
+    have_webp="yes",
+    have_webp="no  (webp library not found)")
+fi
+
+AM_CONDITIONAL(HAVE_WEBP, test "$have_webp" = "yes")
+
+AC_SUBST(WEBP_CFLAGS) 
+AC_SUBST(WEBP_LIBS) 
+
 ######################
 # Check for poly2tri-c
 ######################
@@ -1177,5 +1196,6 @@ Optional dependencies:
   spiro:           $spiro_ok
   EXIV:            $have_exiv2
   umfpack:         $have_umfpack
+  webp:            $have_webp
   poly2tri-c:      $have_p2tc
 ]);
diff --git a/operations/external/Makefile.am b/operations/external/Makefile.am
index b9e7ba2..de8c2ed 100644
--- a/operations/external/Makefile.am
+++ b/operations/external/Makefile.am
@@ -125,6 +125,13 @@ lcms_from_profile_la_LIBADD  = $(op_libs) $(LCMS_LIBS)
 lcms_from_profile_la_CFLAGS  = $(AM_CFLAGS)
 endif
 
+if HAVE_WEBP
+ops += webp-load.la
+webp_load_la_SOURCES = webp-load.c
+webp_load_la_LIBADD  = $(op_libs) $(WEBP_LIBS)
+webp_load_la_CFLAGS  = $(AM_CFLAGS) $(WEBP_CFLAGS)
+endif
+
 # No dependencies
 ops += ppm-load.la ppm-save.la
 ppm_load_la_SOURCES = ppm-load.c
diff --git a/operations/external/webp-load.c b/operations/external/webp-load.c
new file mode 100644
index 0000000..e3cec8e
--- /dev/null
+++ b/operations/external/webp-load.c
@@ -0,0 +1,141 @@
+/* This file is an image processing operation for GEGL
+ *
+ * GEGL is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * GEGL 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with GEGL; if not, see <http://www.gnu.org/licenses/>.
+ *
+ * Copyright 2013 Michael Henning <drawoc darkrefraction com>
+ */
+
+#include "config.h"
+#include <glib/gi18n-lib.h>
+
+
+#ifdef GEGL_CHANT_PROPERTIES
+
+gegl_chant_file_path (path, _("File"), "", _("Path of file to load."))
+
+#else
+
+#define GEGL_CHANT_TYPE_SOURCE
+#define GEGL_CHANT_C_FILE       "webp-load.c"
+
+#include "gegl-chant.h"
+#include <webp/decode.h>
+
+/*XXX: leaks on failure */
+static gboolean
+read_webp (const gchar *path, GeglBuffer *buf, GeglRectangle *bounds_out, const Babl **format_out)
+{
+  GMappedFile *map = g_mapped_file_new (path, FALSE, NULL);
+
+  const gpointer data = g_mapped_file_get_contents (map);
+  gsize data_size = g_mapped_file_get_length (map);
+
+  const Babl* format;
+  GeglRectangle bounds = {0, };
+
+  WebPDecoderConfig config;
+  g_return_val_if_fail (WebPInitDecoderConfig (&config), FALSE);
+
+  g_return_val_if_fail (WebPGetFeatures (data, data_size, &config.input) == VP8_STATUS_OK, FALSE);
+
+  bounds.width  = config.input.width;
+  bounds.height = config.input.height;
+
+  if (config.input.has_alpha)
+    {
+      config.output.colorspace = MODE_RGBA;
+      format = babl_format ("R'G'B'A u8");
+    }
+  else
+    {
+      config.output.colorspace = MODE_RGB;
+      format = babl_format ("R'G'B' u8");
+    }
+
+  if (buf)
+    {
+      g_return_val_if_fail (WebPDecode (data, data_size, &config) == VP8_STATUS_OK, FALSE);
+
+      gegl_buffer_set (buf, &bounds, 1, format, config.output.u.RGBA.rgba,
+                       config.output.u.RGBA.stride);
+
+      WebPFreeDecBuffer (&config.output);
+    }
+
+  if (bounds_out)
+    *bounds_out = bounds;
+
+  if (format_out)
+    *format_out = format;
+
+  g_mapped_file_unref (map);
+
+  return TRUE;
+}
+
+static GeglRectangle
+get_bounding_box (GeglOperation *operation)
+{
+  GeglChantO   *o = GEGL_CHANT_PROPERTIES (operation);
+  GeglRectangle result = {0,0,0,0};
+  const Babl   *format = NULL;
+
+  read_webp (o->path, NULL, &result, &format);
+
+  if (format)
+    gegl_operation_set_format (operation, "output", format);
+
+  return result;
+}
+
+static gboolean
+process (GeglOperation       *operation,
+         GeglBuffer          *output,
+         const GeglRectangle *result,
+         gint                 level)
+{
+  GeglChantO *o = GEGL_CHANT_PROPERTIES (operation);
+  return read_webp (o->path, output, NULL, NULL);
+}
+
+static GeglRectangle
+get_cached_region (GeglOperation       *operation,
+                   const GeglRectangle *roi)
+{
+  return get_bounding_box (operation);
+}
+
+static void
+gegl_chant_class_init (GeglChantClass *klass)
+{
+  GeglOperationClass       *operation_class;
+  GeglOperationSourceClass *source_class;
+
+  operation_class = GEGL_OPERATION_CLASS (klass);
+  source_class    = GEGL_OPERATION_SOURCE_CLASS (klass);
+
+  source_class->process = process;
+  operation_class->get_bounding_box = get_bounding_box;
+  operation_class->get_cached_region = get_cached_region;
+
+  gegl_operation_class_set_keys (operation_class,
+    "name"        , "gegl:webp-load",
+    "categories"  , "hidden",
+    "description" , _("WebP image loader."),
+    NULL);
+
+  gegl_extension_handler_register (".webp", "gegl:webp-load");
+}
+
+#endif
diff --git a/po/POTFILES.in b/po/POTFILES.in
index 1fd6050..6a45ea7 100644
--- a/po/POTFILES.in
+++ b/po/POTFILES.in
@@ -128,6 +128,7 @@ operations/external/text.c
 operations/external/v4l.c
 operations/external/vector-fill.c
 operations/external/vector-stroke.c
+operations/external/webp-load.c
 operations/generated/add.c
 operations/generated/clear.c
 operations/generated/color-burn.c