[rygel/wip/739692: 4/7] server, media-export: Extract media art for videos

[Jens Georg <jensgeorg src gnome org>]

commit b0a112a97ff2092ee64038cb7ceea951bd971ac9
Author: Jens Georg <mail jensge org>
Date:   Tue Nov 11 09:16:40 2014 +0100

    server,media-export: Extract media art for videos
    
    Either use embedded art for files that support it (OGG, MP4,…) or by
    using the same heuristics as for music.
    
    Signed-off-by: Jens Georg <mail jensge org>

 src/librygel-server/rygel-media-art-store.vala     |   50 +++++++++++++++++---
 .../rygel-media-export-item-factory.vala           |   19 ++++++-
 2 files changed, 59 insertions(+), 10 deletions(-)
---
diff --git a/src/librygel-server/rygel-media-art-store.vala b/src/librygel-server/rygel-media-art-store.vala
index b022716..b469881 100644
--- a/src/librygel-server/rygel-media-art-store.vala
+++ b/src/librygel-server/rygel-media-art-store.vala
@@ -88,19 +88,26 @@ public class Rygel.MediaArtStore : GLib.Object {
         return thumb;
     }
 
-    public void add (MusicItem item, File file, uint8[] data, string mime) {
+    public void add (MediaItem item, File file, uint8[] data, string mime) {
         if (this.media_art_process == null) {
             return;
         }
 
+        MediaArt.Type type;
+        string title;
+        if (!this.get_type_and_title (item, out type, out title)) {
+            return;
+        }
+
         try {
-            this.media_art_process.buffer (MediaArt.Type.ALBUM,
+            // Setting artist to " " is a work-around for bgo#739942
+            this.media_art_process.buffer (type,
                                            MediaArt.ProcessFlags.NONE,
                                            file,
                                            data,
                                            mime,
-                                           item.artist,
-                                           item.album);
+                                           item.artist ?? " ",
+                                           title);
         } catch (Error error) {
             warning (_("Failed to add album art for %s: %s"),
                      file.get_uri (),
@@ -108,13 +115,23 @@ public class Rygel.MediaArtStore : GLib.Object {
         }
     }
 
-    public void search_media_art_for_file (MusicItem item, File file) {
+    public void search_media_art_for_file (MediaItem item, File file) {
+        if (this.media_art_process == null) {
+            return;
+        }
+
+        MediaArt.Type type;
+        string title;
+        if (!this.get_type_and_title (item, out type, out title)) {
+            return;
+        }
+
         try {
-            this.media_art_process.file (MediaArt.Type.ALBUM,
+            this.media_art_process.file (type,
                                          MediaArt.ProcessFlags.NONE,
                                          file,
                                          item.artist,
-                                         item.album);
+                                         title);
         } catch (Error error) {
             warning (_("Failed to find media art for %s: %s"),
                      file.get_uri (),
@@ -122,6 +139,25 @@ public class Rygel.MediaArtStore : GLib.Object {
         }
     }
 
+    private bool get_type_and_title (MediaItem item,
+                                     out MediaArt.Type type,
+                                     out string title) {
+        type = MediaArt.Type.NONE;
+        title = null;
+
+        if (item is MusicItem) {
+            type = MediaArt.Type.ALBUM;
+            title = (item as MusicItem).album;
+        } else if (item is VideoItem) {
+            type = MediaArt.Type.VIDEO;
+            title = item.title;
+        } else {
+            return false;
+        }
+
+        return true;
+    }
+
     private MediaArtStore () throws MediaArtStoreError {
         try {
             this.media_art_process = new MediaArt.Process ();
diff --git a/src/plugins/media-export/rygel-media-export-item-factory.vala 
b/src/plugins/media-export/rygel-media-export-item-factory.vala
index a04b455..d6df025 100644
--- a/src/plugins/media-export/rygel-media-export-item-factory.vala
+++ b/src/plugins/media-export/rygel-media-export-item-factory.vala
@@ -211,6 +211,8 @@ namespace Rygel.MediaExport.ItemFactory {
         var color_depth = (int) video_info.get_depth ();
         item.color_depth = (color_depth == 0) ? -1 : color_depth;
 
+        extract_media_art (item, file, audio_info.get_tags ());
+
         return item;
     }
 
@@ -268,6 +270,17 @@ namespace Rygel.MediaExport.ItemFactory {
         tags.get_uint (Tags.TRACK_NUMBER, out tmp);
         item.track_number = (int) tmp;
 
+        extract_media_art (item, file, tags);
+
+        return item;
+    }
+
+    static void extract_media_art (MediaItem item,
+                                   File file,
+                                   Gst.TagList? tags) {
+        if (tags == null) {
+            return;
+        }
 
         var store = MediaArtStore.get_default ();
 
@@ -277,10 +290,12 @@ namespace Rygel.MediaExport.ItemFactory {
             tags.get_sample (Tags.PREVIEW_IMAGE, out sample);
         }
 
+        // Nothing embedded. Do some media art guessing using files located
+        // next to our media file.
         if (sample == null) {
             store.search_media_art_for_file (item, file);
 
-            return item;
+            return;
         }
 
         unowned Structure structure = sample.get_caps ().get_structure (0);
@@ -305,8 +320,6 @@ namespace Rygel.MediaExport.ItemFactory {
             default:
                 break;
         }
-
-        return item;
     }
 
     private static void fill_media_item (MediaItem          item,