Quick and Easy Audio and Video Tips

Working with audio and video media has become easier over the past couple of years. Our hardware has improved and increased in speed; the software has evolved and become less expensive. As our digital video cameras and microphones have changed, it's become easier to move assets around in the digital world. Today, it is possible to use a HD camera and then easily transfer integrated video – for under $150 – that is several times the quality we had just a couple of years ago.

Moving data to your computer

Typically, most internal groups work with other AV groups or with a third party to provide your audio and video services. In either case, you always want to request delivery of the final assets on a hard drive. It is great news if the provider wants to deliver a compressed version because you can use it right away in your e-Learning productions; but always get the highest quality version as well. Having the high-quality version provides you with the flexibility to recompress or edit the content in the future. If you are working with your own equipment, remember to output a hi-res final version or archive your original assets for access in the future.

If you are compressing content for the Web, you want to have the highest quality possible for both video and audio assets, but maintain a small file size so that your learners can easily access the content from home, work, or mobile devices.

Compression tips

The following are practices you can implement internally or with your team to improve the quality of your assets.

Video

When compressing video there are two main factors to consider.

• Frame rate: Video is typically 29.97 frames per second (fps) when pulling it from digital devices. When we compress the content for playback on the Web, we try to reduce it to 10-15 fps. This makes the file size smaller because you are using fewer frames. If you are working with older formats you may need to deinterlace the video when compressing to avoid a ripping effect on playback. You can easily do this on most compression software with a click of a button.

• Codec: A codec is the compression format you choose for playback of your content. The most common format today is H264, which you can use within Flash or HTML5. The compression codec you choose will compress each frame of the video and allow for smaller file sizes, which means quicker downloads or viewing.

Audio

Developers often forget to compress audio when prepping it for the Web, which leads to slower load times and an unnecessary increase in bandwidth. Whether you are outputting audio for use in a Flash project, in Podcasts, or to import into PowerPoint, you can optimize your audio by following these easy steps:

• Selecting a Codec: You can also compress audio using one of several codecs. The most common formats are MP3 or no audio compression. If you are using Flash, then you want to use the MP3 format to keep the audio files small and make it easier for your audience to hear the content as quickly as possible.

• Stereo vs mono: Usually when you record audio, the default is stereo, but you want to convert to mono for most productions. This will reduce your file size by half, which again allows for faster downloads and smaller memory requirements.

• kHz: When you import audio, the resulting sample rate is 44.1 kHz. However, for most audio productions you want to select 22.050 kHz. This also cuts the file size in half and makes it easier for your production to work with multiple files while maintaining the smallest file size.

Compression software

If you have audio or video editing software, you will most likely be able to export directly to one of the formats above. If you are working with dozens of files a day or week, you may want to consider an additional piece of software to optimize your workflow. The following packages are available for both Mac and Windows.

HandBrake

Working with HandBrake (handbrake.fr) open-source compression software for Mac and Windows provides a way to start experimenting and compressing your content. HandBrake's interface is not the best, but once you get past the basics you can easily open a source file and select a compression format. (See Figure 1.) HandBrake offers the ability to batch compress and select a compression format for each file.

Figure 1: HandBrake

Episode

My compression software of choice for the past four years has been Telestream’s Episode. It offers the ability to easily compress your audio or video media into dozens of formats by dragging and dropping your assets and selecting a format or multiple formats to output. (See Figure 2.) Just released is Version 6, which offers a new workflow to make it even easier for newcomers to create workflows and get the optimal outputs. The product starts at $495 and Telestream offers Pro ($995) and Engine ($3,995) versions.

Figure 2: Episode

Instant audio and video publishing

With our need to instantly publish content, aka Web 2.0, the latest phones allow you to directly capture HD video and audio and instantly publish it to YouTube or transfer it to your computer for editing, and then push it to your LMS or Web site. One amazing software and third party service is AudioBoo (audioboo.fm ). This little app – available for the iPhone and Android platforms – allows you to capture an interview or discussion, label and tag it, add a photo, and instantly publish it to the Web for your team or learners to take advantage of.

Figure 3. AudioBoo

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