Tuesday, September 18, 2007

iTunes U Transcoding

I know we're a long way out from fully implementing iTunes U, but one thing that we have already discussed is coming up with standards for the files we will allow to be uploaded. Do we want to make things as easily playable as possible? Then we should perhaps consider using mp3 for sound. AAC and WMA are two other widely used formats, but it is only the rare media player (and especially a portable media device [aka iPod or Zune]) that can play them both. For this reason, mp3 seems to be the safest. But what bit rates to encode at? Do we use CBR or VBR mp3? And I could go on. This problem gets a WHOLE heck of a lot more problematic when dealing with transcoding video, as the format supports are even more varied and the terms of the conversation become even more esoteric.

The role for ECIT will be to provide students and faculty with the tools they need to convert audio or video files into the iTunes U supported format(s). Since our brief is to teach people how to use the technology for themselves, we need something that is not too difficult: preferably with a nice interface. VisualHub is a good example of this. A downside of the product is that it is Mac only. But it is relatively affordable at (as of today) $23.32 US. I haven't found a good example of Windows-based, easy transcoding software. Jim Kruse has suggested that MediaWorks might provide this. This software is nice because it is dual-platform. I haven't sat down to fiddle with it, however, so I can't speak to its abilities yet.

But since we need to be able to work with any format that people bring in, we need to have some backup software that can handle anything that we throw at it. So far, I think that I've identified two options, both of which are free and both of which, unfortunately are Windows only. My personal vote is for MediaCoder. It's interface is nothing to write home about and you can get lost in the options. However, it has a number of "Extensions" built into it that offer more or less one-step transcoding of files into formats suitable for a variety of different devices. What's more, you can design your own Extensions very easily (although sorting through all the options is daunting). My mp3 player hasa built-in mic, and I use MediaCoder to transcode the WAV files into manageable mp3s.

Another option, with an even worse interface is Super. I've not had much experience with it, but it also appears to be a powerful tool to get things from one format to another.

I'd give MediaCoder an 85 and Super a 93 on the User Learning Curve (ULC), where 0 is my grandmother and 100 is the evil spawn of Sergey Brin and Larry Page. They are not easy to use or learn. However, I think their advantage is that they could be distributed for free to the entire Emory Community via Software Express or the EOL CD. And if my dreams of guerrilla recording are to come to fruition across the campus, then we'll want everyone to have the tools in her/his room to get the materials uploaded to iTunes U as soon as possible.

If you're interested in seeing what other software I'm finding for the purposes of transcoding, check my list of ECIT+transcode bookmarks at del.icio.us.

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