Streaming audio and video content across a network is a broad topic, from
real time connections replacing a traditional AM matrix switch to conferencing
to cat videos on YouTube with a huge range of mix and match technologies in any
given solution. Choosing the right solution involves considering both the
application and content attributes and narrowing down the technologies that do
not support those attributes.
REAL TIME OR ON DEMAND?
The first step in characterizing the streaming application is determining if the application is real time (live), or on demand.
Live streaming technologies are appropriate for time sensitive applications such as, live lectures or television transport, or ones where interaction with the audience is required. Any production, such as switching between content sources or subtitles will have to be done within the integrated video capture system.
On demand video allows for more sophisticated production and editing with only the level of effort you are willing to put into it limiting the final product. It is appropriate when the content is not time sensitive or should be available over time. On demand video allows for individual controls such as pause and rewind, since each stream is individually sent to the consumer.
A hybrid approach where a live event is streamed and also captured for on demand availability is very common. Often these hybrid systems have limited editing capabilities to trim the start and stop times and add bookmarks. Otherwise, the captured video can be exported to a video editing program for more complete editing. If this is an application requirement, then the workflow involved in getting the captured content to be available on demand should be explored to make sure it meets the requirements.
The purpose of streaming content is to deliver information to the audience. It is important to characterize the audience to make sure the content reaches them and has the required properties for them to effectively consume it.
Who is consuming the stream and
It is important to understand the size of the audience in terms of simultaneous users to properly choose from the various technologies available. Other important considerations include:
»»Understanding the requirements for quality based on the audience requirements. The quality acceptable for a cute cat video may not be acceptable for something that requires close examination like an advanced math class.
»»The length of time they are viewing. Poor quality audio and video is taxing to watch. Longer content generally requires higher quality. If the content is on demand and the users want to consume part of the content and continue later, perhaps on another device, it needs to be considered before the system is chosen.
Where are they?
This is a network consideration. It is important to know how the audience is accessing the content relative to the source. Possibilities include:
In the same room. The content is streamed as an alternative to traditional AV distribution. Examples include; streaming the presentation computer to a shared display or streaming content such as a video camera, attached microscope, to a display at each student’s workspace.
On the same campus. The content is available with very few network restrictions because source and content are on the same Local Area Network (LAN).
In the same enterprise. The source and audience may be at different locations, but content is streamed across a network completely under the control of the enterprise.
On the Internet. At least part of the network is completely out of the control of the organization. Available network bandwidth may be unknown and devices such as firewalls may need to be traversed.
What are they viewing the stream
You can no longer assume that streaming is being consumed on set top boxes or computers. The audience may want to consume the video on phones, tablets, video game systems, or any combination of operating systems and player software. Consideration must be made based on the audience what types of playback devices will be supported.
Do they have special requirements?
Are there any special requirements required to meet the goals of the streaming system? Some possible special requirements include:
»» Keyword searches to find sections of the
»» Closed captioning
»» Verification or reports that the content has been viewed
»» Ability to view multiple simultaneous content streams (presenter camera and content)
Tolerance for delay or latency is perhaps the least understood critical attribute and is among the hardest to quantify. There are large differences in latency tolerance for different use cases ranging from almost no latency to several seconds (or minutes).