Podcasting in the Classroom

1. Podcasting in the Classroom Presented by: Jason Arruzza, AIS

2. What is Podcasting? • a digital audio file (usually MP3 or AAC) made available for download on the internet through an RSS 2.0 feed. • The web address of the media file is contained in the enclosure tag of an item in the XML file. • A podcast's RSS feed is updated each time a new media file is published. • An aggregator for podcasts (such as iTunes or iPodder) is used to subscribe to the RSS feed.

3. Who can podcast? • anyone can create their own “radio”-style show and broadcast it to the world in very little time and at very little cost. • required: a computer, a mic and the internet.

4. http://audacity.sourceforge.net/

5. What is Audacity? • Audacity is a rapidly evolving multi-platform soundfile editor that is freely available • Audacity 1.2.3 includes: • a good set of editing tools, • support for Linux Audio Developer's Simple Plugin API (LADSPA) effects, • multitrack recording capability. • Its user interface is well-designed, uncluttered and simple to navigate. • Supported file formats include WAV, AIFF, AU, SND, and MP3; Audacity also exports to OGG format. • Standard cut/copy/paste operations are supported as well as Undo/Redo functions.

6. Resources • Audacity homepage/download • http://audacity.sourceforge.net/ • Audacity Help, FAQ, etc • http://audacity.sourceforge.net/help/documentation • Audacity Tutorials • http://audacity.sourceforge.net/help/tutorials • Audacity wiki • http://audacityteam.org/wiki/ • Audacity User Manual • http://audacity.sourceforge.net/audacity-manual-1.2.zip

8. About sound files • The most popular and most common cross-platform uncompressed audio file formats are .AIFF (Audio Interchange File Format - Mac) and .WAV (Microsoft Windows Wave). • both support 16-bit, 44 KHz stereo and polyphonic sound (sound with more than two channels). • this quality is approximately 10MB per minute in size since it is high quality). • audio file formats include u-law, which use the suffix .au and so are often called AU files • MPEG audio (suffix .mpeg and .mpg). MPEG files are compressed (ie: ~ 1/5 the size of a.wav or .aiff file) but with a slight loss of quality. • When creating a sound file can set preferences to adjust the quality of the file by adjusting Bit Rate, Channel and Sample Width • basically choosing a mono channel together with the lowest sample width and the lowest sample rate you will create a lower quality, smaller file. • Ogg is an advanced binary audio format similar to the mp3 format. It is patent and royalty free, and is supported on most platforms.

9. Bit Rate • is the frequency at which bits are passing a given "point". • quantified using the bit per second (bit/s) unit. • bit rate measures number of bits/time • 4 kbit/s – minimum necessary for recognizable speech • 8 kbit/s – telephone quality • 32 kbit/s – MW quality • 96 kbit/s – FM quality • 128 kbit/s – CD quality Source: Wikipedia

10. Audacity Activity: • Import a sound/music file into a track • Record a new voice track over • Edit as necessary • Add effects • Save as.mp3 file

11. Contact Details • Jason Arruzza • Education Consultant – ICT Across the Curriculum • Level 4, 99 York Street, Sydney NSW 2000 • Phone (02) 9299 2845 Fax (02) 9290 2274 • Web aisnsw.edu.au Email jarruzza@aisnsw.edu.au • ABN 96 003 509 073