MULTIMEDIA DATABASES -Define data -Define databases

Multimedia data typically means digital images, audio, video, animation and graphics together with text data. The huge amount of data in different multimedia related applications warranted to have databases that provide consistency, concurrency, integrity, security and availability of data. Database provides functionalities for the easy manipulation of query and retrieval of highly relevant information from huge collections of speed data.

MULTIMEDIA DATABASES 1.Multimedia Storage and Retrieval –Massive Data Volumes –Storage Technologies –Multimedia Object Storage –Multimedia Document Retrieval 2.Database Management Systems for Multimedia Systems –RDBMS Extensions for Multimedia –Object-Oriented Databases for Multimedia 3.Database Organization for Multimedia Applications –Data Independence –Common distributed database architecture –Distributed database servers –Multimedia object management 4.Transaction Management for Multimedia Systems

1.1 Multimedia Storage and Retrieval Multimedia storage is characterized by a number of new considerations: –Massive storage volumes –Large object sizes –Multiple related objects –Temporal requirements for retrieval

Massive Data Volumes Paper records and films or tapes are difficult to integrate, control, search and access, and distribute. Locating paper documents, films, and audio or video tapes requires searching through massive storage files, complex indexing systems understood only by a few key staff personnel.

Storage Technologies There are two major mass storage technologies used for storage of multimedia documents. -Optical Disk Storage Systems -High Speed Magnetic Storage Managing a few optical disk platters in a jukebox is much simpler than managing a much larger magnetic disk form. Optical disk storage is an excellent vehicle for offline archival of old and infrequently referenced documents for significant periods of time.

Multimedia Object Storage Multimedia object storage in an optimal medium serves its real purpose only if it can be located rapidly and automatically. A key issue is random key access to various components of a hypermedia document or hypermedia database. Optical media provides very dense storage. For instance, a 12 inch optical disk platter can store 6.5Gbytes of information.

Continue….. A compressed 8bit sound clip requires 50kbytes/sec. Decompression efficiency. Retrieval speed is a direct result of –The Storage latency –Compression efficiency –Transmission latency Imaging is essential for retrieval of information

Multimedia Document Retrieval The simplest form of identifying a multimedia document is by storage platter identification and its relative position on the platter (file number). These objects can be grouped using a database in folders or within complex objects representing hypermedia documents. This is the method for identifying images in most multimedia systems. An application for sound and full motion video is the ability to clip parts of it and combine them with another set.

1.2 Database Management Systems for Multimedia systems Most multimedia applications are based on communication technologies such as Electronic Mail, the database system must be fully distributed. A number of database storage choices are available. They are: –Extending the existing RDBMS to support the various objects for multimedia as binary object. –Extending RDBMS beyond basic binary objects to the object oriented components of inheritance and classes. –Converting to a full fledged object oriented database that supports the standard SQL languages. –Converting the database and the application to an object- oriented database and using object-oriented language, such as C++.

RDBMS Extensions for Multimedia BLOB (Binary Large OBject) is a datatype for binary free form text and images. BLOBs are used for objects such as images or other binary data types. Relational database tables include location information for the BLOBs which may actually be stored outside the database on separete image or video servers. An object oriented database supports both, –Encapsulation –Inheritance

1.3. Database Organization for Multimedia Application