Chapter 5: Realizing a Metadata Framework 151 shows the big picture (the context) which an individual object belongs to. This also implies that any single application cannot take ownership of metadata and claim that it is solely responsible for it. Metadata is indeed system-wide information, and its management a part of the operating system. Thus, our framework is designed to be part of the operating system, providing services to all applications with any metadata, for any needs they may have. Our framework stores all metadata for all content objects only once. This is done regardless of the content type. So music, photos, and video clips are all treated equally. The result is that all applications are pro- vided with a unifi ed access to both content and metadata. 5.4.2 Separating Metadata from Content Binaries One of the fi rst decisions regarding the metadata framework was to separate metadata from the actual content binaries to increase the scalability and performance of distributed content management. Since metadata is stored in a database with a link to the content binary, fi nding and updating metadata is fast – there is no need to fi nd, read, and parse metadata from within the content binaries. The framework also indexes the metadata for effi cient searching. This means that to fi nd all songs with “Anvil” as an artist, all you need is a simple query to the database, with a list of links to the actual content objects as a result. There is nothing new in this, since the separation of metadata and content is a common practice amongst media applications. Almost all applications that need to handle large amounts of metadata, such as iTunes or UPnP media servers, do it for the same reasons. The differ- ence in our solution is that all metadata, regardless of the content type, is available for any application. Storing metadata in a database makes searching faster and simpler, makes it a lot easier to handle metadata that belongs to more than one content binary, and enhances the general metadata management by removing the need to manage the actual binaries. Having all metadata in a database fi le makes creating backups easy and fast. Most personal content is priceless, therefore, it is important to keep the amount of content that needs to be backed up as small as possible. Even though editing images, videos, and other media content in mobile devices becomes easier and more popular, as tools and methods eventually improve, modifying the binary content of the media occurs rarely compared to events and other related metadata updates. Every time you play a song or watch a movie, some changes in metadata take place – at least the play count and last accessed