Podcasting

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Podcasting is a distribution mechanism for audio and video content. There are many areas on the UNL campus currently utilizing podcasting for digital media distribution - check with your local IT staff for more information and technical support. If you are looking for a unit that provides podcasting services, contact the following individuals.

City Campus:
Todd Jensen 
New Media Center Manager,
Information Services
(402)472-0606
newmedia@unl.edu
East Campus:
Mark Hendricks or Mike Kamm
Communications & Information Technology
(402)472-3035


Contents

iTunes U

iTunes U is a directory of university content available through the iTunes store. UNL's presence within iTunes U serves as a directory of UNL podcast content.

Entry Page

http://itunes.unl.edu/

Discussion

Podcast Glossary

Glossary of terms used in audio, video and podcast production.

Podcast Glossary

Production Applications

Podcast Producer, available in Mac OS X Server 10.5 'Leopard,' has built in and customizable work flows that can help streamline the encoding and branding of content. For example, a piece of video content can be sent to Podcast Producer and encoded in a variety of formats, watermarked with a university logo, have bumper video content added to the front and back, and added to iTunesU. A separate application, Podcast Capture, is included with the client version of Mac OS X 10.5 (Leopard).

http://www.apple.com/server/macosx/leopard/podcastproducer.html

UNL Webcast Project is an initiative to utilize Podcast Producer and other tools to enable easier audio and video capture, edit, and distribution to various channels including iTunesU. A collaboration among many departments including Information Services, University Communications, and CIT has created a working group to implement a system of this nature.

Format Recommendations

iTunes U supports the distribution of compressed audio and video files. As you consider which formats and file sizes to produce, keep in mind that your users will need to download the content from your site and that their bandwidth may vary. For longer-form video content, consider using a lower resolution or breaking the content into pieces.

Audio

  • Audio files (AAC, MP3) with appropriate file extensions (.m4a, .mp3).

For best results during playback, Apple recommends converting MP3 files larger than 32MB to AAC format. For AAC audio files, use the following specifications:

Audio format: AAC-LC (Music) 
Data rate: 128 Kbps 
Channels: Stereo 
Output sample rate: 44.100 kHz 
Encoding quality: Better

Video

The following information has been taken from Apple document "Podcasts - Technical Specification." For best results with AppleTV, newer-generation iPods, and other viewers, use QuickTime Pro's "Movie to iPod" function, or another compressor that produces an MPEG-4 h.264 file with the following specifications:

Video format: MPEG-4 with H.264, low-complexity baseline profile
Data rate: up to 1.5Mbps 
Image size: 960 by 540 
Frame rate: 30 
Key frame: Every 24 frames
Audio: AAC-LC up to 160 kbps, 48 Khz, stereo

If you use QuickTime to create and edit video content, Apple recommends that you export your videos by choosing â�?��?Movie to iPodâ�?� from the Export pop-up menu in QuickTime Pro (see Video for iPod and Apple TV, page 4). This will create an MPEG-4 file with the .m4v extension, which is generally registered to iTunes. If you want the file to be used with other viewers, you may change the file extension to .mp4.

- OR -

If bandwidth is a consideration for your audience, you may wish to encode your video according to Apple's earlier recommendations:

Video format: MPEG-4 with H.264 
Data rate: 256 Kbps 
Image size: 640 by 480 
Frame rate: 30 
Key frame: Every 24 frames

Metadata

iTunes U requires a specially formatted RSS feed with additional info for clients.

The Apple website has detailed specifics of a sample RSS feed, as well as details on additional tags from the itunes namespace which you can add to your feeds.

Resources

Training

Communications & Information Technology Electronic Media is currently in production of a series of podcast training modules, to be delivered via podcast, specific to podcasting within the University of Nebraska - Lincoln environment. If you have ideas for the production, please contact Mark Hendricks or Mike Kamm.

Podcast Training Draft Outline

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