Which video and audio standard should I use?

People like standardisation it makes life easier, it is easier to provide advice and guidance and removes barriers. The implication is that if everyone used the same device, the same formats and the same delivery mechanisms then it would be easier to deliver video and audio to learners and for those learners to create audio and video themselves.

Audio is a little easier to standardise, most people have heard of mp3 and most devices can play mp3 files. That should make it much easier to roll out, however due to the fact there is a patent behind mp3 and licensing fees that need to be paid, means that some devices though can play mp3s can not record direct to mp3. These devices will use other audio codecs that play fine on the device in question, but not necessarily on other devices or through a browser. The solution in Gloucestershire College was to standardise on the Edirol R09H which records natively to mp3 onto an SD memory card. Yes it is expensive, but it does record to mp3 and the quality is excellent. Use of SD cards meant that it was very easy to transfer recordings to a laptop or computer and then share them on the VLE. The quality of the audio recordings were excellent.

Of course though the mp3 standard is ubiquitous, recording to mp3 is not necessarily the best format to use, especially if you are going to do any kind of editing on the recording. If for example you are going to be using Garageband to edit the recording and create a podcast, then you are not going to want to use the mp3 format. The reason is that an mp3 file is compressed and uses what is called a lossy compression, in other words information is lost when the file is compressed. If you edit and then compress again, more information is lost. As a result you are compressing a compressed format and you will lose even more quality. This means you can get a less than satisfactory recording. For those who prefer a higher quality the Edirol R09H can also record direct to uncompressed WAV. This is CD quality and doesn’t use any lossy compression, so no loss of quality when editing the file. Of course the problem with WAV is that the file sizes are large so distribution is a problem, so the final edited audio file can then be compressed to mp3.

It’s one thing to record audio, delivery is something else. Placing the audio file on the VLE makes it very easy for learners to access and download the recording in their browser. However for regular recordings it makes more sense to use RSS or podcast the recordings. This will allow learners to subscribe to the series of recordings through software such as iTunes and then transfer the recordings to a portable device such as an iPhone or iPod. The challenge here is not just technical, but also the recognition from practitioners of the importance of a regular series of recordings or podcasts.

If audio is difficult video is much more challenging. Different cameras and devices record video using different formats and even when they use the same format, they may use a different codec. Modern operating systems generally have few problems using MP4 video files, both Windows 7 Media Player and OS X QuickTime X can play modern MP4 video files. Many mobile devices and smartphones can play MP4 files too. However one of the challenges facing FE Colleges is that many are still using Windows XP which doesn’t natively support MP4 and isn’t from a networking perspective the easiest to add that functionality.

One solution is to upload the video to sites such as Vimeo or YouTube and use Flash. Flash is often the solution to the delivery of video on networks where native MP4 playback isn’t possible. The issue with Flash video is how do you deliver such video on mobile devices, many of which don’t have support for Flash? Also how do you deliver the video to mobile devices that are not network connected? Another issue is privacy, the problem with using sites such as YouTube is that they are public and it may not be possible or wanted that the videos are public.

A key technological challenge for institutions is to answer all those problems without it becoming a barrier to learners and practitioners.

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