Media Galleries API: Audio/Video attached pictures support.

chrome/common/extensions/api/media_galleries.idl

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Use the <code>chrome.mediaGalleries</code> API to access media files (audio,
 // images, video) from the user's local disks (with the user's consent).
 namespace mediaGalleries {
 
   [inline_doc] enum GetMediaFileSystemsInteractivity {
     // Do not act interactively.
     no,
     // Ask the user to manage permitted media galleries.
     yes,
     // Ask the user to manage permitted galleries only if the return set would
     // otherwise be empty.
     if_needed
   };
 
   [inline_doc] enum GetMetadataType {
-    // Retrieve all available metadata.
+    // Retrieve the mime type, metadata tags, and attached pictures.

[vandebo (ex-Chrome), 2014/04/23 23:22:45]

Is there any benefit (speed?) to retrieving the attached pictures [maybe images
is a better word here] and not the tags?

[tommycli, 2014/04/29 00:15:51]

Not sure, but I doubt it. At least in the FFMpeg code flow, to access the
attached pictures, you would have already read-in the media file's headers (with
its metadata).

     all,
+    // Retrieve only the mime type and the metadata tags.
+    mimeTypeAndTags,
     // Retrieve only the mime type.
     mimeTypeOnly
   };
 
   [inline_doc] enum ScanProgressType {
     // The scan started.
     start,
     // The scan was cancelled.
     cancel,
     // The scan finished but none of the result have been added,
@@ skipping 108 matching lines @@
     DOMString? copyright;
     long? disc;
     DOMString? genre;
     DOMString? language;
     DOMString? title;
     long? track;
 
     // All the metadata in the media file. For formats with multiple streams,
     // stream order will be preserved. Container metadata is the first element.
     StreamInfo[] rawTags;
+    
+    // The pictures embedded in the media file's metadata. This is most often

[vandebo (ex-Chrome), 2014/04/23 23:22:45]

s/pictures/images/

[tommycli, 2014/04/29 00:15:51]

Done. You mean just the comment, and not all the variable names right? (I used
'pictures' just because that's how ffmpeg refers to it. I have no objection to
using images everywhere if that makes more sense to you)

[vandebo (ex-Chrome), 2014/04/29 16:09:03]

images is shorter and more general than pictures, but I care much more about the
public interface.

[tommycli, 2014/04/29 22:57:00]

Done.

+    // used for album art or video thumbnails.
+    [instanceof=Blob] object[] attachedPictures;
   };
 
   callback MediaMetadataCallback = void (MediaMetadata metadata);
 
   interface Functions {
     // Get the media galleries configured in this user agent. If none are
     // configured or available, the callback will receive an empty array.
     static void getMediaFileSystems(optional MediaFileSystemsDetails details,
                                     MediaFileSystemsCallback callback);
 
@@ skipping 39 matching lines @@
                             optional MediaMetadataOptions options,
                             MediaMetadataCallback callback);
   };
 
   interface Events {
     // The pending media scan has changed state. See details for more
     // information.
     static void onScanProgress(ScanProgressDetails details);
   };
 };