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Resource Guides

Introduction

A Special Note on Copyright

Audio for Web Pages
--Introduction

--Recording Devices

--Basics

--File Formats

--Capturing Digital Audio

--Short Web Clips

--Longer, Edited Web Clips

--High-Quality Web Audio

MIDI:  High-Tech Player Pianos
--Introduction

--MIDI and the Web

--Creating MIDI Files

Video for Web Pages
--Introduction

--Cameras and Techniques

--Capturing Video

--Video Web Formats

Common Questions

Sound and Video in CourseInfo

Links to Resources



Tutorial: Sound and Video for the Web and Blackboard

Audio for Web Pages:  Working With Longer, Edited Sound Clips

In Windows, a third-party program is required if you wish to capture and edit sound clips that are longer than 30-60 seconds. This is particularly true if you wish to save the audio in formats that are accessible by users on a variety of computer platforms on the Internet or if you wish to clean the audio with filters and add effects such as a “fade in” or “fade out”.

Three programs are available free or as shareware for the Windows platform that can be used for capturing and initial editing of longer sound clips: DD Clip Light, Goldwave, and CoolEdit. For larger projects, such as audio restoration or extensive editing and mixing, a commercial program such as Sound Forge would be useful. (SoundEdit, by Macromedia, is a similar program for the Macintosh.)


Screen shot of CoolEdit, a shareware sound recording and editing program for Windows.

See the Links to Resources section of this tutorial to see a list of some software packages that are available.

Current versions of the programs are available at many download sites, such as http://download.cnet.com/. DD Clip Light is a full-featured editor that allows you to mix up to four audio tracks and work with video. Goldwave and CoolEdit act as more full-featured versions of the Windows Sound Recorder and allow for editing or filtering of a sound clip and conversion of the clip to different formats. The site also includes shareware and freeware programs with similar functionality for the Macintosh.

Creating AU Files for Internet Use

AU files are a standard for the Unix platform and are widely used on Web sites for short sound clips. Most Web browsers are capable of playing AU files without an additional plug-in or helper application.

Using one of the third-party programs mentioned above, you record the sound and edit it in a similar manner as you would in the Microsoft Sound Recorder application. You can choose “File” and “Save As” to choose which format you wish to save it – the file will be saved as an AU sound file. (Again, note that some more recent versions of the Microsoft Sound Recorder provided with Windows can save AU files.)

You can choose the sound quality to save or format the file based on the intended use. Again, 22 KHz sounds can be used for medium-quality speech or music.

Using Real Audio on a Web Page

Real Audio can be used quite effectively on Web sites, particularly sites that are targeted to a larger audience that might be using a modem connection. The format uses a special player from Progressive Networks and your visitor will need the player, but it is probably the most common media player currently installed on Internet-connected computers. The file sizes are the smallest of the various audio formats we are discussing in this Guide, which translates into more accessibility to your sound clips by more users.

Real Audio uses compression to take out repetitive information in the digital audio. Three levels of compression are available, depending on the content and your intended audience, and provide varying levels of audio quality.

To create a Real Audio file, first capture the clip using the Windows Sound Recorder or a third-party software package such as DD Clip, GoldWave, or CoolEdit. Save the sound clip as a WAV file – make sure you capture the clip with the best quality available on your system and do any desired filtering or editing before conversion to Real Audio.  Progressive Networks has a Real Audio/Video encoder available for free from their Web site (http://www.real.com/).


Screen shot of the Real Audio encoder for Windows.

After installing the encoder program on your computer, you can tell the encoder the name of your WAV sound file and the file name and location for the resulting Real Audio file. The illustration below shows the encoder and the menu you use to choose the compression level – just click on the “Start” button to begin the conversion.

updated 4.6.00
riddlera@duke.edu

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