Transcript 4_hardware - Personal web pages for people of Metropolia

Lecture 4: Multimedia Hardware
Introduction
 The word platform was traditionally
associated with hardware: the
computer platform.
 However, it can also describe
software as well as hardware (Mac
platform vs. Windows platform)
 WWW: the platform is the
combination of browser, computer
and OS (+ plug-ins)
Introduction
 For an offline application the OS and computer
is generally enough but sometimes more
detail, such as the graphics adapter, is
important
 Definition: The platform is whatever you have
to specify in order to run the application
 What kind of display is needed, or how big
hard disk, or how fast Internet connection
Introduction
 Three options that will be discussed in
relation to platforms:
 The delivery platform: what does your
user have to use in order to see your
application?
 The delivery medium: how do you get
the application to the user?
 The development and testing platform:
what do you need to use in order to
make the application in the first place?
Selection of the proper platform
 Selection of the proper platform for
developing your multimedia project may be
based on




your personal preference of computer
your budget constraints
project delivery requirements
the type of material and content in the project
 Today you can produce multimedia projects
with equal ease in either the Windows or
Macintosh environment
Memory and storage devices




RAM and ROM
Hard drives
CD-ROM, DVD, BlueRay
USB memory modules
Input devices










Keyboards
Mice
Touchscreens
Magnetic Card Encoders and Readers
Graphics Tablets
Flat-bed Scanners
OCR Devices (Optical CharacterRecognition)
Infrared Remotes
Voice Recognition Systems
Digital Still and Video Cameras
Output hardware






Audio Devices
Amplifiers and Speakers
Monitors
Video Devices
Projectors
Printers
Communication devices





Cable Modems
xDSL technologies
Wireless (WLAN)
3G/4G
etc…
Online delivery
 WWW is somewhat simple for publishing since all web
browsers understand HTML; the web is the most
cross-platform format (despite some issues with
JavaScript and ActiveX etc).
 Issues affecting the delivery on Internet:
 Speed of access
 Updating
 Security/payment
 The “unlimited” size of the data space than can be
provided online
 You can restrict access, charge users for access, and
even keep track of who has accessed your information
and when
Online delivery
 The speed with which your potential users can access
your application is unpredictable; tens of Kbps – tens of
Mbps
 The bottleneck is the end-user’s web connection
 Do what you can: have a fast server and a fast Internet
connection
 Streaming and buffering are methods that try to remove
the problem of download times
 ONLINE DELIVERY PRO’S &CONS?
(groupwork)
Online delivery – pros and cons
 Pros
 A low cost and sophisticated possibilities
 The application can be fixed at any time
 Potentially an infinite amount of space to hold
information
 The web’s reach is global and instant
 Cons
 a heterogeneous user base
 you need to decide how much you can cater for
the differences in the users’ systems
 Security implications
 Slow connections
Mobile multimedia
 Mobile applications do not differ that
much from conventional computer
delivery
 The bandwidth problem is more
important, since it may be very
dependent on your distance from a
base station
 At least the billing is easy since the
system always tracks down the user
Interactive television
 The arrival of digital television brings with it
the possibility of interactive services
 Set-top boxes for televisions; also
integrated models are available; IPTV
 Video-on-demand (VOD) may provide
another market for interactive services on
the TV or via net to a PC (push and pull
models)
 Today’s set-top boxes use push model
Delivery medium
 Besides deciding on what computer
platform the end-user will actually
use your production, there is the
question of how you will actually
distribute the content.
 If it’s a web page, then the WWW is
the medium
 To a certain extent this will depend
on the size of the application, and
might even have been specified up
front
Optical disks
 This medium has become universal; it may
never lose its supremacy as a carrier
 Different incarnations: CD-ROM, DVD,
BlueRay
 DVD and BlueRay are higher-density
formats than CD (the basics of the
technologies are quite similar)
 Replication of optical disks is cheap
 Especially for movie delivery
Hybrid delivery
 Sometimes you can use both on- and
offline delivery (quite common today)
 Web links can be part of DVDs
 DVDs are often updated from the web
(fixes and additions are saved on the
hd)
Platforms for development
and testing
 You do not have to develop your application
on the delivery platform
 A cross-platform application is usually
developed on one and tested on all delivery
platforms (even a low-level code can be
produced on a different computer using a
cross-compiler)
 Even though majority of multimedia
applications are created for Windows, they
are quite often developed on Macintosh
(not that much anymore, but few years ago
the software was usually first released for
Mac)
Platforms for development and
testing
 Create and manipulate your assets (sound,
graphics etc) in the highest convenient
standard and convert down, if necessary, at
the last moment
 You must have at least one workstation that is
similar to the delivery platform so that you can
test the performance and carry out debugging
 Remember that you can never have
all possible platform combinations
Author once and deliver
everywhere
 We need techniques that allow us to author
once an deliver on many platforms
 XML is one part of the solution to this: it
allows the content structure to be
separated from the way it is laid out; layout
can change depending on the platform
 Although we are talking about media
convergence, the range of platforms
available is still increasing