[rygel] media-export: Extract embedded album art

[Zeeshan Ali Khattak <zeeshanak src gnome org>]

commit b330119b4942c94db7bbb5e7ad4758fba0383a44
Author: Jens Georg <mail jensge org>
Date:   Sat Jul 24 23:19:03 2010 +0300

    media-export: Extract embedded album art

 configure.ac                                       |    4 +
 src/plugins/media-export/Makefile.am               |    7 ++
 .../media-export/rygel-media-export-item.vala      |   26 ++++++++-
 .../rygel-media-export-jpeg-writer.vala            |   66 ++++++++++++++++++++
 4 files changed, 102 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 2735b76..84e0ef9 100644
--- a/configure.ac
+++ b/configure.ac
@@ -27,6 +27,8 @@ GUPNP_DLNA_REQUIRED=0.2.1
 GUPNP_VALA_REQUIRED=0.6.7
 DBUS_GLIB_REQUIRED=0.74
 GSTREAMER_REQUIRED=0.10.23
+GSTREAMER_TAG_REQUIRED=0.10.28
+GSTREAMER_APP_REQUIRED=0.10.28
 GIO_REQUIRED=2.16
 GEE_REQUIRED=0.5.2
 UUID_REQUIRED=1.41.3
@@ -278,6 +280,8 @@ AM_CONDITIONAL([BUILD_GST_LAUNCH_PLUGIN], [test "x$enable_gst_launch_plugin" = "
 if test "x$enable_media_export_plugin" = "xyes";
 then
     PKG_CHECK_MODULES(LIBSQLITE3, sqlite3 >= $LIBSQLITE3_REQUIRED)
+    PKG_CHECK_MODULES(GSTREAMER_TAG, gstreamer-tag-0.10 >= $GSTREAMER_TAG_REQUIRED);
+    PKG_CHECK_MODULES(GSTREAMER_APP, gstreamer-app-0.10 >= $GSTREAMER_APP_REQUIRED);
 fi
 
 # Gettext
diff --git a/src/plugins/media-export/Makefile.am b/src/plugins/media-export/Makefile.am
index c65cb0b..34e1c8a 100644
--- a/src/plugins/media-export/Makefile.am
+++ b/src/plugins/media-export/Makefile.am
@@ -15,6 +15,8 @@ AM_CFLAGS = $(LIBGUPNP_CFLAGS) \
 	    $(LIBSQLITE3_CFLAGS) \
 	    $(GEE_CFLAGS) \
 	    $(UUID_CFLAGS) \
+	    $(GSTREAMER_TAG_CFLAGS) \
+	    $(GSTREAMER_APP_CFLAGS) \
 	    -I$(top_srcdir)/src/rygel -DDATA_DIR='"$(datadir)"' \
 	    -include config.h
 
@@ -32,6 +34,7 @@ librygel_media_export_la_SOURCES = rygel-media-export-plugin.vala \
 				   rygel-media-export-recursive-file-monitor.vala \
 				   rygel-media-export-harvester.vala \
 				   rygel-media-export-item.vala \
+				   rygel-media-export-jpeg-writer.vala \
 				   rygel-media-export-writable-container.vala \
 				   rygel-media-export-object-factory.vala
 
@@ -44,6 +47,8 @@ librygel_media_export_la_VALAFLAGS = --vapidir=$(top_srcdir)/src/rygel \
                                      --pkg libsoup-2.4 \
                                      --pkg gee-1.0 \
                                      --pkg libxml-2.0 \
+                                     --pkg gstreamer-tag-0.10 \
+                                     --pkg gstreamer-app-0.10 \
                                      --pkg sqlite3 -g
 
 librygel_media_export_la_LIBADD = $(LIBGUPNP_LIBS) \
@@ -51,6 +56,8 @@ librygel_media_export_la_LIBADD = $(LIBGUPNP_LIBS) \
 				  $(LIBGUPNP_DLNA_LIBS) \
 				  $(LIBDBUS_GLIB_LIBS) \
 				  $(LIBGSTREAMER_LIBS) \
+				  $(GSTREAMER_TAG_LIBS) \
+				  $(GSTREAMER_APP_LIBS) \
 				  $(LIBSQLITE3_LIBS) \
 				  $(GEE_LIBS) \
 				  $(UUID_LIBS)
diff --git a/src/plugins/media-export/rygel-media-export-item.vala b/src/plugins/media-export/rygel-media-export-item.vala
index 9b73808..f9c7114 100644
--- a/src/plugins/media-export/rygel-media-export-item.vala
+++ b/src/plugins/media-export/rygel-media-export-item.vala
@@ -188,8 +188,32 @@ public class Rygel.MediaExport.Item : Rygel.MediaItem {
               MediaItem.MUSIC_CLASS);
 
         if (audio_info.tags != null) {
-            uint tmp;
+            unowned Gst.Buffer buffer;
+            audio_info.tags.get_buffer (TAG_IMAGE, out buffer);
+            if (buffer != null) {
+                var structure = buffer.caps.get_structure (0);
+                int image_type;
+                structure.get_enum ("image-type",
+                                    typeof (Gst.TagImageType),
+                                    out image_type);
+                switch (image_type) {
+                    case TagImageType.UNDEFINED:
+                    case TagImageType.FRONT_COVER:
+                        var store = MediaArtStore.get_default ();
+                        var thumb = store.get_media_art_file ("album",
+                                                              this,
+                                                              true);
+                        try {
+                            var writer = new JPEGWriter ();
+                            writer.write (buffer, thumb);
+                        } catch (Error error) {}
+                        break;
+                    default:
+                        break;
+                }
+            }
 
+            uint tmp;
             audio_info.tags.get_uint (TAG_BITRATE, out tmp);
             this.bitrate = (int) tmp / 8;
         }
diff --git a/src/plugins/media-export/rygel-media-export-jpeg-writer.vala b/src/plugins/media-export/rygel-media-export-jpeg-writer.vala
new file mode 100644
index 0000000..675bfd2
--- /dev/null
+++ b/src/plugins/media-export/rygel-media-export-jpeg-writer.vala
@@ -0,0 +1,66 @@
+/*
+ * Copyright (C) 2010 Jens Georg <mail jensge org>.
+ *
+ * Author: Jens Georg <mail jensge org>
+ *
+ * This file is part of Rygel.
+ *
+ * Rygel 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 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Rygel 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 this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+using Gst;
+
+/**
+ * Utility class to write media-art content to JPEG files
+ *
+ * This uses a gstreamer pipeline to transcode the image tag as contained in
+ * MP3 files. This class is single-shot, use and then throw away.
+ */
+internal class Rygel.MediaExport.JPEGWriter : GLib.Object {
+    private Bin bin;
+    private AppSrc appsrc;
+    private MainLoop loop;
+    private dynamic Element sink;
+
+    public JPEGWriter () throws Error {
+        this.bin = Gst.parse_launch ("appsrc name=src ! decodebin2 ! " +
+                                     "ffmpegcolorspace ! " +
+                                     "jpegenc ! giosink name=sink") as Bin;
+        this.appsrc = bin.get_by_name ("src") as AppSrc;
+        this.sink = bin.get_by_name ("sink");
+        var bus = bin.get_bus ();
+        bus.add_signal_watch ();
+        bus.message["eos"].connect(() => { this.loop.quit (); });
+        bus.message["error"].connect(() => { this.loop.quit (); });
+        this.loop = new MainLoop (null, false);
+    }
+
+    /**
+     * Write a Gst.Buffer as retrieved from the Gst.TagList to disk.
+     *
+     * @param buffer The Gst.Buffer as obtained from tag list
+     * @param file   A GLib.File pointing to the target location
+     *
+     * FIXME This uses a nested main-loop to block which is ugly.
+     */
+    public void write (Gst.Buffer buffer, File file) {
+        this.sink.file = file;
+        this.appsrc.push_buffer (buffer);
+        this.appsrc.end_of_stream ();
+        this.bin.set_state (State.PLAYING);
+        this.loop.run ();
+        this.bin.set_state (State.NULL);
+    }
+}