Preparing Content

Production, Post-Production, Distribution

In the field of audio/video media creation, production refers to the writing, recording and filming of the original content. Post-production refers to the process of editing, mixing audio and video sources, and final preparation for distribution. Distribution is the actual delivery of the final product.

OIT’s streaming server offers only content distribution.

Media Services

OIT partners with the Media Services’ Video Production unit for production and post-production of media content. UCI Media Services provides multimedia and television production services to all campus departments, and can help faculty and instructors prepare and upload multimedia content for on-line distribution. For example, presentations, pre-taped lectures and demonstrations can be converted into a streaming format.

Departments with the resources to independantly produce, post-produce and upload content are welcome to do so.

Delivery Mechanism

The act of distributing digital media is generally accomplished through one of two methods: downloading or streaming. Whether content is made available via either method, or both, depends on the content provider’s goals as well as the consumer’s ability to view or listen to the content.

When a user downloads content, that content is copied to the consumer’s device (a computer or handheld player) and stored for later playback. In some cases, this manner of distribution is referred to as podcasting. Such distribution offers a great convenience for consumers to review content while “offline,” such as while commuting. However, the content must be downloaded in its entirety, prior to being away from the network.

Streaming enables real-time distrubition and reception of audio, video and multimedia on the Internet. As the data is transferred and displayed concurrently, playback can begin as soon as enough data has been received; on fast connections, very little time elapses between the user’s action and the display of content.

Live events may be streamed over the Internet, and archived for later download.

Digital Media Formats

In distributing digtial audio/video content, publishers are confronted with the choice of a media format. In choosing a format, publishers should consider: whether the content is intended for a conventional personal computer, or a portable device; playback abilities likely to be found in the playback device; the demographics of the intended viewing audience and any inclinitions which may be inherent to that audience; whether an end-user will be inclined to install an unfamiliar player.

In general, publishers should adopt formats and codecs which present the least barrier to playback; end users should be able to quickly and easily view or listen to the content. Consideration should also be given to vendor lock-in, open standards, and the ability to migrate one’s content to another popular format.

The OIT streaming media server supports the following major formats:

Format File Extension Notes
Flash Video .flv Popularly used on the Web, for playback within browsers (e.g. YouTube, GoogleVideo). The FlashPlayer plugins are included with most web browsers. Dreamweaver’s “Insert Flash Video” allows for easy inclusion in web pages; supports FLV (video), MP3 (audio) and MP4 (AVC/H.264 video) files.
MPG .aac, .m4a, .m4v, .mp3, .mp4, .mpg Vendor-independent industry standard; audio and video variations are widely supported in playback software and devices. The AVC/H.264 (MPEG4 Part 10) video standard is supported by Flash, Apple iTunes and QuickTime software, and the iPod, PSP, and Zune portable players.
QuickTime .mov Supported by iTunes software and iPod players. Included with Mac OS X, installed with iTunes on Windows computers. Commonly used in content creation; well-supported for conversion into other formats.
RealMedia .ra, .rm, .rv Popular in streaming to mobile phones. Playback requires installation of the (free) RealPlayer software.
Windows Media .wma, .wmv Included with Windows, playback on Mac OS X via the Flip4Mac plugins. Supported on a variety of portable devices.

 

Device Resolutions, Data Bitrates

Publishers should consider providing content in multiple formats, in order to serve different styles of consumption. For exampls, an audio/video lecture might also be provided in an audio-only format, in order that it can be downloaded to a small portable device. Similarly, a large-format video presentation intended for a computer screen, and also be optimized for a small portable player.

Audio
The most widedly supported formats for audio are MP3 and AAC. Generally, MP3 requires a higher bitrate in order to yield the same audible quality.

  • Lecture – 24kbps, mono
  • Music, low fidelity – 96kbps, stereo
  • Music, high fidelity – 192kbps, stereo

Video
Quality of video results can vary widely, depending on the conversion software and settings used.

Example Resolution and Data Rates Using AVC/H.264
Use Scenario Resolution & Frame Rate Example Data Rates
Mobile Content 176×144, 10-15 fps 50-60 Kbps
Internet/Standard Definition 640×480, 24 fps 1-2 Mbps
High Definition 1280×720, 24p 5-6 Mbps
Full High Definition 1920×1080, 24p 7-8 Mbps