This document discusses audio file formats for cross-platform use between Macintosh and Windows PCs. It describes the different file formats used on each platform, with Macs using .AIFF or .SDII files and Windows using .WAV files. The most common cross-platform format is MP3, which reduces file size while maintaining sound quality. The document also discusses playing audio files over the internet, either by downloading the full file first or streaming the audio as it downloads.

1.  Describe the various audio files formats suitable for cross
platform work.

2. In This Chapter, you’ll learn on:
 The differences between Macintosh and Windows
PC
 The term ‘file format’.
 The types of audio files used in the following
platforms :-
o Macintosh - .AIFF or .SDII data files
o Windows - .WAV
o Cross Platform
 The common sound file formats used for the
Internet.

3.  Macintosh versus PC
 Macintosh The Macintosh or Mac, is a series of personal
computers designed, developed, and marketed by Apple
Inc. The first Macintosh was introduced by Apple's then-
chairman Steve Jobs on January 24, 1984;
 it was the first commercially successful personal computer to
feature a mouse and a graphical user interface rather than
a command-line interface.
 The company continued to have success through the
second half of the 1980s, first primarily because of the sales
of the Apple II series remained strong even after the
introduction of the Macintosh, only to see it dissipate in the
1990s as the personal computer market shifted toward the
"Wintel" platform: IBM PC compatible machines running MS-
DOS and Microsoft Windows

4.  Macintosh versus PC
 Years later, Apple consolidated its multiple consumer-level
desktop models into the 1998 iMac all-in-one. This proved to
be a sales success and saw the Macintosh brand revitalized.
Current Mac systems are mainly targeted at the home,
education, and creative professional markets. These include
the descendants of the original iMac and the entry-level
Mac mini desktop models, the Mac Pro tower graphics
workstation, the MacBook, MacBook Air and MacBook Pro
laptops. The Xserve server was discontinued January 31,
2011.

5.  Macintosh versus PC
 Production of the Mac is based on a vertical integration
model in that Apple facilitates all aspects of its hardware
and creates its own operating system that is pre-installed on
all Mac computers. This is in contrast to most IBM PC
compatibles, where multiple sellers create and integrate
hardware intended to run another company's operating
software. Apple exclusively produces Mac hardware,
choosing internal systems, designs, and prices. Apple does
use third party components, however, such as graphics
subsystems from nVidia and ATi.

6.  Macintosh versus PC
 Current Mac CPUs use Intel's X86-64 architecture; the earliest
models (1984–1994) used Motorola's 68k and models from
1994–2006 used the AIM alliance's PowerPC. Apple also
develops the operating system for the Mac, currently Mac
OS X version 10.7 "Lion". The modern Mac, like other personal
computers, is capable of running alternative operating
systems such as Linux, FreeBSD, and, in the case of Intel-
based Macs, Microsoft Windows. However, Apple does not
license Mac OS X for use on non-Apple computers.

7.  Macintosh versus PC
 Since it’s beginning the Macintosh (Mac) has been the defined
as multimedia computer. While Mac had a good built-in audio
the IBM personal computer (PC) could not process sound
without very expensive add-on components. With its focus on
business computing, the PC remained for many years to
provide only system beeps and limited sound effects on a tiny
onboard speaker.


8.  Macintosh versus PC
 Recently, due to high demand of game software lower-cost
soundboards and software have become available for PCs.
Other multimedia tools and hardware are now readily
available for PCs. When installed with Windows, sound and
graphics cards PC readily challenge the Mac in delivering
excellent audio and video. A Multimedia PC (MPC) computer
will always provide sound capability. The MPC is an industry
wide effort begun in late 1980s to provide a standardized and
capable multimedia-computing environment for PCs.
 All Mac can play sound. Mac includes hardware and software
for digitising sound without additional hardware or sound cards.
The AV Series of Mac can digitise video as well as sound.

9.  Macintosh versus PC
 Windows MPC
 A personal computer (PC) is any general-purpose computer
whose size, capabilities, and original sales price make it useful
for individuals, and which is intended to be operated directly
by an end-user with no intervening computer operator. In
contrast, the batch processing or time-sharing models allowed
large expensive mainframe systems to be used by many
people, usually at the same time. Large data processing
systems require a full-time staff to operate efficiently.

10.  Macintosh versus PC
 Windows MPC
 Software applications for personal computers include, but are
not limited to, word processing, spreadsheets, databases, Web
browsers and e-mail clients, digital media playback, games,
and myriad personal productivity and special-purpose software
applications. Modern personal computers often have
connections to the Internet, allowing access to the World Wide
Web and a wide range of other resources. Personal computers
may be connected to a local area network (LAN), either by a
cable or a wireless connection. A personal computer may be a
desktop computer or a laptop, tablet, or a handheld PC.

11.  Macintosh versus PC
 Microsoft Windows is a series of operating systems produced by
Microsoft.
 Microsoft introduced an operating environment named
Windows on November 20, 1985 as an add-on to MS-DOS in
response to the growing interest in graphical user interfaces
(GUIs). Microsoft Windows came to dominate the world's
personal computer market, overtaking Mac OS, which had
been introduced in 1984. As of August 2011, Windows has
approximately 82.58% of the market share of the client
operating systems according to Usage share of operating
systems.

12.  Macintosh versus PC
 The most recent client version of Windows is Windows 7; the
most recent server version is Windows Server 2008 R2; the most
recent mobile version is Windows Phone 7.
 While early PC owners usually had to write their own programs
to do anything useful with the machines, today's users have
access to a wide range of commercial software and free
software, which is provided in ready-to-run or ready-to-compile
form. Since the early 1990s, Microsoft software and Intel
hardware have dominated much of the personal computer
market, first with MS-DOS and then with the Wintel platform

13.  Macintosh versus PC
 The MPC computer is not hardware but rather a standard that
includes minimum specifications to turn Intel-microprocessor
based computers into a multimedia computers. The standard
applies not only to desktop computers but also to multimedia
laptops.
 Because the MPC is a standard, not a computer, we can
assemble MPC from various suppliers and meet the standard.

14.  What is “file format”?

 When you create multimedia, it is likely that you will
deal with file formats.
 A sound file format is simply a recognized
methodology for organizing the digitized sound’s
data bits and bytes into a data file. The structure of
the file must be known before the data can be
saved and loaded into a computer to be edited
and/or playback as sound.

15.  Working with audio in Macintosh
 On Macintosh, digitised sound is stored as data files (file
extension .AIF or .SDII), or they may be stored as resources
in the resource fork of the system or application as .SND
 QuickTime is a standard file format for displaying digitised
motion video. Digital audio data is interleaved with video
information in the file. The audio stays synchronized to the
picture. QuickTime can be used to play stereo sound and
MIDI files.
 Macintosh can make use of MIDI files with the MIDI
adapter at the input and output devices.

16.  Working with audio in Windows
 Windows includes standardized support for both digital audio
and MIDI.
 Microsoft has established a common audio file format called
the wave audio format (.WAV) files. It is a standardized method
of storing digital audio information.
 Cross Platform Audio Files
 The most popular for Mac and PCs these days is MP3. This
format is a compression system for audio files. MP3 file size is
rather small. It reduces the bytes in the audio while maintaining
the sound quality. Due to the small file size, it is also easy to
download.

17.  Working with audio in the Internet
 There are two methods for playing either digital audio or MIDI
files on the Internet.

 i. Download the entire audio file to the computer and play it
back with a helper application.

 ii. Let the audio file streams into the computer, i.e. begin to
play a downloading audio as soon as enough of the audio is
cached on the computer. There will always be more audio
waiting to be played than still needs to be downloaded.
Streaming files are dependent upon connection speed : longer
time waiting before the streamed audio begins when using a
28.8Kbps modem (low bandwidth) than when using a
broadband.

18.  New formats are emerging as companies develop solution for
streaming and playing sound on the Web.
 To work with the Internet, one must work within the
requirements of the appropriate protocol, using documents
and formats that are recognizable.
 The Internet uses a standard list of file name extensions called
MIME-types [Multipurpose Internet Mail Extensions]
 For example a voice attachment to an e-mail message must
be identified and transmitted with the correct coding to the
receiving computer. The receiver must have the proper
software and hardware for decoding the information and
playing it back.
 Most browser allow you to define additional MIME-types. For
example with Netscape Navigator you can define Adobe’s
Acrobat files (.PDF) as a MIME-type and select Acrobat Reader
as the player application.