Recommended Media Formats

Podcasting or Web Playback/Download Audio
Format: mp3
Sample Rate: 44100Hhz,
Bit Rate: 128kbits/sec
Filesize: Small, 1MB/minute

Converting audio to mp3 in iTunes directions here

Video Podcasting (Vodcasting)
Format: MPEG-4 (.mp4 for Web or .m4v for iTunes/iPods)
Codec: H.264
Resolution:: 640 x 480 (4:3 source) or 640 x 360 (widescreen 16:9 source) at 24 frames per second
Average Bit Rate: 512kbps
Filesize: Large, 5MB/minute

A note on producing video for iPods: it is recommended that your source file is at least 640 pixels wide and that you use the built-in iPod converters in Compressor ("H.264 for iPod"), QuickTime Pro ("Movie to iPod") or iTunes ("Convert Selection for iPod"). Each of these maintains the aspect ration of your source file and results in an .m4v file containing H.264 video (Low Complexity version of the Baseline profile) and AAC-LC audio. See the tutorial for creating iPod video in Quicktime Pro for step-by-step directions. You can also do this in the iTunes application by dragging the file into the Movies library and converting it by simply right-clicking the video (control-click on mac) and choosing "Convert Selection for iPod".

Retaining Editable Content

It is recommended that, regardless of where you publish digital media, you retain your own archive copies in formats that have minimal loss of quality and can be edited and re-encodec later. This future-proofs your content to some extent if media standards change or you'd like to distribute your content through a new technology.

Some recommended formats:

Audio, lossless and uncompressed for recording, editing, and archiving
Format: WAV
Sample Rate: 44100Hhz, 16 bit
Filesize: Large, 10MB/minute

Some Notes on Copyright

Duke has a wonderful resource from our Scholarly Communications Officer, in the form of a blog: http://library.duke.edu/blogs/scholcomm/

Apple has provided a useful primmer for content publishers: http://images.apple.com/support/itunes_u/docs/iTunes_U_Copyright_Overview.pdf

If you plan commercial distribution of content, please consider the licensing requirements of various technologies. For example, you may wish to use AAC for audio instead of MP3.