1. Possible solutions to the R limitations
Multimedia Databases
Possible solutions to the R limitations

2. Topics Covered Why multimedia is a problem for databases
Support for searching
Types of Databases
Relational Databases and Multimedia
Example - Access
Object Relational Databases and Multimedia
Example - Oracle
Object Oriented Databases and Multimedia
Example - Jasmine

3. The problem - recap
Data increasingly means not just numbers and small strings but multimedia data as well – structured (text, images, video, audio, VR, etc.)
Databases promise:
well structured data organisation
efficient storage of large amounts of data
querying
transactional support for concurrent users
If you include multimedia data
multimedia is large and may swamp other data
multimedia data structures are completely different from standard database structures
multimedia data structures do not easily lend themselves to content-based searching

4. Data integration
Databases already integrate various kinds of data, numbers, dates, small text strings.
They do this by the use of domains
i.e. each atomic value in the database belongs to one of a small number of types
each type has two aspects:
a range of values which are acceptable
some operations which are available

5. Cont ….
the schema indicates a domain for each part of the database and the DBMS enforces the domain constraint
e.g. in a Relational Database, each column is assigned a domain
Therefore a DBMS must provide domain types for any kind of data that they wish to house and theoverall structure will deal with the integration

6. Domain types of MM data
DBMS typically provide three different kinds of domain for multimedia data:
large object domains, sequences of data often of two kinds
Binary Large Objects – BLOBs – which are an unstructured sequence of bytes
Character Large Objects – CLOBs – which are an unstructured sequence of characters
file references – instead of holding the data, a file reference contains a link to the data (OLE in Access)
genuine multimedia data types – (Oracle and Jasmine)

7. Cont …
There is an important difference between the last of these and the first two:
multimedia data types present the possibility of exploiting the structure of the data for querying and manipulation
large objects at best allow you to extract sections or to concatenate them
file references mean that the DBMS has no access the data at all

8. Querying MM data
A DBMS permits a user to search the database by content e.g. give the name of the student with matriculation number We would like to do the same with multimedia data e.g. give the pictures painted by Picasso or sound files with female singer hitting top C
With standard data this is easy – numeric and string operators are well understood With multimedia data this is more difficult and requires some method of identifying contents of which there are two kinds:

9. Cont … automatic identification manual identification
an algorithm takes the data and returns a measure which can be compared – e.g. of blackness
manual identification
a person examines the data and catalogues it – e.g. in a table of pictures, there is a column for the picture and another for the painter

10. Types of Database
There are three kinds of DBMS that might be used for housing multimedia data.
Relational DBMS store everything as First Normal Form tables
all data items are atomic and are held in rectangular tables
data can only be related if they are in one or in two records connected by a common value (foreign key)
records are identified only by content
it is difficult (if not impossible) to extend the set of domains

11. Cont … Object-oriented DBMS store everything as classes of objects
all data is held as components of objects (like Java variables)
data is related by object reference (i.e. one class variable has a type which is another class and the values of that variable are instances of that class)
the set of classes is extensible and so you can freely create domains

12. Cont …
Object-relational DBMS are fundamentally relations but are not First Normal Form
the values in cells can be object references as well as atomic values
new types can be defined

13. How can we use these different types?
In a relational database, you can have:
domain types for large objects
using a string type for file names
extra file types as in OLE in Access
In an object-oriented database, you can have:
specially designed classes for multimedia
In an object-relational database, you can have:
specially designed types for multimedia

14. R type database e.g. Access and OLE
Object Linking and Embedding was Microsoft’s first architecture for integrating files of different types:
Each file type in Windows is associated with an application It is possible to place a file of one type inside another:
either by wholly embedding the data in which case it is rendered by a plug-in associated with the program
or by placing a link to the data in which case it is rendered by calling the original program
Access works with this system by providing a domain type for OLE
• There’s not much you can do with OLE fields since the data is in a format that Access does not understand
• You can plug the foreign data into a report or a form and little else

15. R databases e.g. BFILEs in Oracle
The BFILE datatype provides access to BLOB files of up to 4 gigabytes that are stored in file systems outside an Oracle database.
The BFILE datatype allows read-only support of large binary files; you cannot modify a file through Oracle. Oracle provides APIs to access file data.

16. Large Object Types in Oracle and SQL3
Oracle and SQL3 support three large object types:
BLOB - The BLOB domain type stores unstructured binary data in the database. BLOBs can store up to four gigabytes of binary data.
CLOB – The CLOB domain type stores up to four gigabytes of single-byte character set data
NCLOB - The NCLOB domain type stores up to four gigabytes of fixed-width and varying width multi-byte national character set data
* SQL3 is a significant extension to standard SQL which turns into a full object-based language

17. Cont … These types support
Concatenation – making up one LOB by putting two of them together
Substring – extract a section of a LOB
Overlay – replace a substring of one LOB with another
Trim – removing particular characters (e.g. whitespace) from the beginning or end
Length – returns the length of the LOB
Position – returns the position of a substring in a LOB
Upper and Lower – turns a CLOB or NCLOB into upper or lower case
LOBs can only appear in a where clause using “=”, “<>” or “like” and not in group by or order by at all

18. Large Object Types in MySQL
MySQL has four BLOB and four CLOB (called TEXT in MySQL) domain types:
TINYBLOB and TINYTEXT – store up to 256 bytes
BLOB and TEXT – store up to 64K bytes
MEDIUMBLOB and MEDIUMTEXT – store up to 16M bytes
LONGBLOB and LONGTEXT – store up to 4G bytes

19. Oracle interMedia Audio, Image, and Video
Oracle interMedia supports multimedia storage, retrieval, and management of:
BLOBs stored locally in Oracle8i onwards and containing audio, image, or video data
BFILEs, stored locally in operating system-specific file systems and containing audio, image or video data
URLs containing audio, image, or video data stored on any HTTP server such as Oracle Application Server, Netscape Application Server, Microsoft Internet Information Server, Apache HTTPD server, and Spyglass servers
Streaming audio or video data stored on specialized media servers such as the Oracle Video Server

20. The Object Relational Multimedia Domain Types in interMedia
interMedia provides the ORDAudio, ORDImage, and ORDVideo object types and methods for:
updateTime ORDSource attribute manipulation
manipulating multimedia data source attribute information
extracting attributes from multimedia data
getting and managing multimedia data from Oracle interMedia, Web servers, and other servers
performing a minimal set of manipulation operations on multimedia data (images only)

21. Cont … The properties available are:
ORDImage – the height, width, data size of the on-disk image, file type, image type,compression type, and MIME type
ORDAudio – the format, encoding, number of channels, sampling rate, sample size,compression type, and audio duration
ORDVideo – the format, frame size, frame resolution, frame rate, video duration, number of frames, compression type, number of colours, and bit rate

22. Cont … Oracle also stores metadata including:
source type, location, and source name
MIME type and formatting information
characteristics such as height and width of an image, number of audio channels, video frame rate, pay time, etc.

23. OO databases – e.g. Jasmine
Jasmine is an Object-Oriented database and has an application known as Studio is its development environment
It comes with a number of built in classes include four multimedia classes:
Picture -
Image –
Video –
Audio -
These come with manipulation and compression facilities They also have been made to fit well with Java Media Framework

24. conclusions
At present you can not do much with MM data, there are two reasons for this:
1. It is very large
indexing on multimedia data is not reasonable nor is storing a default value
other retrieval may be slowed down
transactions may be compromised
2. The properties are not well understood or implementable in reasonable time
what does it mean to say that one image is before another in order therefore there are few operators in the where clause that work

25. Cont ..
At the moment, there is no reason for putting multimedia data into a relational database
it just slows everything down
and you can’t do very much
You could use an object relational or object oriented database
now you can do more
but the products are immature
and everything will be slow

26. Cont …
There are three main reasons for integrating multimedia data with a database:
1. Cataloguing the data
a column for file names is good enough
2. Decorating Reports
The OLE approach works well here Otherwise a file name column and a simple application for generating the reports would do
3. Web Applications
Again a file name column is good enough