1. 4.2 Multimedia Elements 4.2.4 Audio 1

2. Learning Outcomes: At the end of the lesson, students should be: a) describe the purpose of using audio in multimedia. b) identify sources of audio. c) identify different types of file format. 2

3. Audio ● Any sound-- music, voice, narration ● An important element in multimedia. ● Without sound, presentation will be dull. Wave 3

4. Types of Audio ● Analog ● Digital 4

5. Analog AudioDigital Audio the original sound signal. we can record analog audio file. special audio editors like Audacity can be use to convert analog audio files into digital audio files. the digital sampling of the actual sound used in multimedia. Types of audio

6. ANALOG AUDIO ● The sound that we hear everyday is in the form of analog. ● a form of signals that moves in a continuous wave. ● Sound is recorded over a microphone = analog sound. ●This kind of sound or analog signals cannot be transmitted through a computer. 6

7. DIGITAL AUDIO ● Computer recognizes sound in digital format. ● Computer will process data into electronic form and not from the physical movement in the air. ● The sound used in multimedia applications are in digital form. ● Comprise of the binary code is represented by 0 and 1. ● Digital music, digital video or digital image, the computer only recognizes it as bits. ● When the analogue wave enters the computer, it will be digitized or in technical term, has been sampled. 7

8. Purpose of Audio ● Increases the multimedia attraction. It adds excitement. ● more real and memorable. ● Can capture attention. ● as a guide for the users. ● to enhance the interest while maintaining the attention. ● to attract the users ● to influence user’s emotional and thoughts ● to increase the understanding of complex contents through audio explanation 8

9. Audio AdvantagesDisadvantages It ensures the delivery of vital information. Overuse. Unique capacity to provide caution or reminder to the users about some specific information. Requires special equipment to generate high quality products. Increases the multimedia attraction where music, narration or sound effects further enhance the multimedia application that was previously quite static. Users must possess the right equipment to generate high quality sound. - 9

10. The Role of Audio ● Warnings and reminders. ● Background Music. ● Sound effects. ● Narration ● Data that is related to sound 10

11. 11 Sources of Audio Pre-Package Buying and Borrowing Own Invention

12. 12 Pre-Package ● can be obtained from the computer's operating system. ● from programs that already exist in your computer.

13. 13 Figure 3: Sound file in Microsoft Office

14. 14 Buying and Borrowing ● bought from companies that specialize in production of sound clips. ● The Internet is the right place to purchase sound clips. - free download.

15. 15 Own Invention ● Created easily by using specific program together with a microphone. ● Must consider about quality of the sound to be generated. ● For example: - sound into a PowerPoint presentation, you can use a medium quality sound.

16. 16 Audio Software ● Audio management is very important to generate good multimedia products. ● Requires specific software for recording purposes or for the audio production. ● Audio recording for Microsoft Windows operating system: - Sound Recorder. ● Example : - Sound Forge - SoundEdit 16 - audacity

17. 17 Sound Forge ● has internal support to record video and CD. ● can store a lot of video and audio file formats. ● has excellent editing features such as cut, mute, reverse, and trim. ● has amazing effects. ● support many file formats ● It is easy to use. Audio Software

18. 18 Audio Software SoundEdit 16 ● can do editing for more than 10 audio formats. ● can import and export AU file formats from the Internet. ● support compression such as algorithm compression 4:1 for a 16-bit voice.

19. 19 File Format ● Sound or music can be recorded in a variety of formats. ● Most of these audio file formats involve compressing the audio files. ● Types of File Format:.aiff.au.wav.midi.mp3

20. 20 File Format MP3 (Motion Picture Expert Group Layer 3 format) ●MP3 file is the sound part of MPEG files. ●Allows various sampling rates and bit rates. ● Most popular sound format for music - High quality and good compression(Small file size). ● Popular for sound transmission on the Internet. ● Capable of storing additional textual information such as the subject, artist's name and comments.

21. 21 wav ● This audio format is developed by IBM and Microsoft. ● The main and popular audio format in the Microsoft Windows operating system environment. ● Can supported by all computers running Windows and by all the most web browser (except Google Chrome) File Format

22. 22 MIDI (Musical Instrument Digital Interface) ● Is a format audio for electronic music device like synthesizer and PC sound card. ● Its doesn't contain sound, but digital music instruction (notes) that can be played by electronic device (like PC's sound card) ● MIDI files are small ● MIDI is supported by all the most popular web browser. File Format

23. 23 AIFF (audio interchange file format) ● Is a audio format file standard used for storing sound data for PC and other electronic audio device. ● Most commonly used on Apple computer system. ●AIFF files generally end with.AIF or.IEF extension ●Doesn't support data compression – tend to large. File Format

24. 24 RealAudio (.rm /.ram) ● The real audio format was developed for the Internet by real media. ● The format file for real audio are.rm and.ram ● Its support video format. ● Allows streaming of audio with low bandwidth. File Format

25. 25 Common Types of Audio Format Type Extensions Code AIFF (Mac).aif,.aiff*PCM AU (Sun/ Next).au*u-law CD audio (CDDA)N/APCM MP3.mp3MPEG Audio Layer-III Windows Media Audio.wmaProprietary (Microsoft) QuickTime.qtProprietary (Apple Computer) RealAudio.ra, ramProprietary (Real Networks) WAV.wav*PCM File Format