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Multimedia Techonology Introduction Course. Present
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Introduction to
Multimedia TechnologyCourse
Ghifar
Overview Multimedia course in
Informatics Engineering UNPAR
Introduction to Multimedia
Compression: A handy invention
MULTIMEDIA COURSE@ INFORMATICS ENGINEERING UNPAR
Multimedia Tech. Course
What will you learn ? Graphics/Image, Audio, and Video
Representation
Compression Algorithms and Techniques
Compression Standards
JPEG, H.261, MPEG, etc
Digital Rights
State-of-The-Art Multimedia TechVoIP
Video conference
INTRO TO MULTIMEDIA
What is Multimedia ? When different people mention the term multimedia,
they often have quite different, or even opposing, viewpoints A PC Vendor : a PC that has sound capability, a DVD-ROM
drive, and perhaps the superiority of multimedia-enabled microprocessors that understand additional multimedia instructions
A consumer entertainment vendor: interactive cable TV with hundreds of digital channels available, or a cable TV-like service delivered over a higher speed internet connection
A Computer Science (CS) student: applications that use multiple modalities, including text, images, drawings (graphic), animation, video, sound including speech, and interactivity
Multimedia and CS : Graphics, HCI, visualization, computer vision, data
compression, graph theory, networking, database systems
Components of Multimedia Multimedia involves multiple modalities
of text, audio, images, drawings, animation, and video. Examples of how these modalities are put to use:
Video teleconferencing
Distributed lecturers for higher education
Tele-medicine
Co-operative work environments
Searching in (very) large video and image databases for target visual objects
Augmented reality: placing real-appearing computer graphics and video objects into scenes
Components of Multimedia (2)
including audio cues for where video-conference participants are located
build searchable features into new video, and enabling very high-to very low bit-rate use of new, scalable multimedia products
Making multimedia components editable & distributed
Video understanding => “Inverse-Hollywood”
Using voice & speech Recognition to build an interactive environment, say a kitchen-wall web browser
Multimedia Research Multimedia processing & coding
multimedia content analysis, content-based multimedia retrieval, multimedia security, audio/image/video processing, compression, dll
Multimedia system supports & networking
network protocols, internet, operating systems, servers and clients, quality of service (QoS), databases
Multimedia tools, end-systems & applications
hypermedia systems, user interfaces, authoring systems
Multi-modal interaction and integration
“ubiquity” – web-everywhere devices, multimedia education (Computer Supported Collaborative Learning), design and applications of virtual environments
Current Multimedia Projects
1. Camera-based object tracking technology
2. 3D motion capture :used for multiple actor capture so that multiple real actors in a virtual studio can be used to automatically produce realistic animated models with natural movement
3. Multiple views : allowing photo-realistic (video-quality) synthesis or virtual actors from several cameras or from a single camera under different lighting
4. 3D capture technology : allow synthesis of highly realistic facial animation from speech
Current Multimedia Projects (2)
5. Specific multimedia applications : aimed at handicapped persons with low vision capability and the elderly – a rich field of endeavor
6. Digital fashion : aims to develop smart clothing that can communicate with other such enhanced clothing using wireless communication, so as to artificially enhance human interaction in a social setting
7. Electronic Housecall system : an initiative for providing interactive health monitoring services to patients in their homes
8. Augmented Interaction applications : used to develop interfaces between real and virtual humans for tasks such as augmented reality
Let’s watch some interesting videos ….
Compression : A handy invention
That handy invention can answer the questions here
Do you eager to know :
How does the ZIP/RAR application work?
How can images be sent and loaded fast via Internet ?
Why can the VoIP be implemented ?
How can video be streamed through the relatively narrow communication lines ?
The obvious example Suppose we have a string :
“ABCCCCCCCCDEFGGGG“ (17 characters)
By exploiting some redundancies, we can rewrite that string so that become : “ABC!8DEFG!4” (now only 11 characters)
“!” refers to the next character is the frequency of the previous character
Min. 4 same consecutive chars
Is there any disadvantage ?
Run-Length Coding (RLC)
“Ask not what your country can do for you - ask what you can do for your country”
- John F. Kennedy -“ask” appears 2 times“what” appears 2 times“your” appears 2 times“country” appears 2 times“can” appears 2 times“do” appears 2 times“for” appears 2 times“you” appears 2 times
The Second Example: note this famous quotation below…
How can we compress the quotation ?
One of the method is using the “dictionary”
Supposed this is our dictionary :
Our sentence now reads :
Lempel & Ziv adaptive dictionary-based
What about compressing other multimedia besides text ?
The 2 previous compression techniques are simply not enough to compress multimedia data such as image, audio, or video
For others, sometimes they need more sophisticated encoding algorithm or advanced math. computation to compress more data
Discrete Cosine Transform (DCT)
Karhunen-Loeve Transform (KLT)
Continuous Wavelet Transform (CWT)
Discrete Wavelet Transform (DWT)
Embedded Zerotree of Wavelet Coefficients (EZW)
The Principals of Compression
From previous examples, we can summarize 2 main factors :
1. Data Redundancy Number of repetitions/occurrences,
spatial redundancy, temporal redundancy
2. Human Perception Generally, human perception is not
sensitive with small errors
Have an error tolerance without really affecting the effectiveness of the communication
Types of Compression1. Lossless Compression
You have already seen the example The compression result must able to
be decompressed ! But, it’s not really small enough e.g. : ZIP, RAR, GZIP, binary program,
some of GIF and PNG images
2. Lossy Compression The compression result needs not to
be decompressed It’s enough to be used the smaller
form The result size is far smaller than
“the lossless” e.g. : JPEG, MP3, MPEG
Is there any difference ?
Summary for Compression
Compression is the process of encoding information user fewer bits than the original
Reduce the consumption of expensive resources, such as hard disk space or transmission bandwidth
There are numerous methods of compression techniques which some of them are suitable with the specific multimedia data and others are not.
Principals of compression : Data Redundancy and Human Perception
Types of compression : Lossless and Lossy
ANY QUESTION
THANK YOU