Video Streaming Content CreationKeywords - broadcast tv,broadcast television,pal,ntsc,secam,pal video |
Content Creation
The designer of the content will use various production tools to create the content. These tools convert audio, video, or animation to a data type format that the server can stream. Because most servers can deliver content in many different formats, there are a number of tools that people can use in creating content. Production tools can epitomize the content for efficient delivery over the Internet, based on the nature of the material and the capabilities of the client computers.
Each of the big three provides tools for creating or converting content into a format that can be handled by their servers and epitomized for Internet Streaming. RealNetwork's RealProducer 10 will convert from a number of raw formats (AVI, MPEG-1, AU, AIFF etc) and is free for the basic version. Apple's Quicktime Player (free and pro) also provides content authoring and import/export facilities
A more complete (and more expensive - upwards of 600 US dollars) product is Media 100's Media Cleaner 5. Cleaner 5 is a complete suite of tools for preparing video and audio for the web and is considered the industry leader in this field.
The content creator can also create a Synchronized Multimedia Integration Language (SMIL) file to synchronies several clips within a presentation. A SMIL file co-ordinates the layout and playing of two or more media clips in parallel (simultaneously) or in sequence. A typical example of this is a lecture or presentation with associated slides where the presentation of the slides can be synchronized with the audio content of the lecture.
RealNetworks have put the most effort into developing SMIL for the web and have created proprietary formats of RealText, RealPix, RealVideo, RealAudio and RealFlash for use within a SMIL script. SMIL version 3.0 is currently in draft and will enhance the language significantly.
Creating content with SMIL (which is based on XML) takes more time and effort but the results are worth it. Oratrix Development program for GRiNS is a editor to create SMIL texts. There are many examples on the web showing how, for very little bandwidth, excellent media rich presentations can be compiled which are much more informative and interesting than the statically presented video.
Local experience has shown that it is not usually sufficient to simply encode existing video content for streaming. Content producers need to be cognizant of the tremendous compression ratios that are common in this arena. Subtle visual information is lost and picture sizes will be small. Limited camera movement is important as is good lighting, simple backgrounds and close ups of subject material.
All the systems have ways of making it easy to provide a single link for users encompassing multiple data rates. This means that your files can stream without the user having to specify a particular bandwidth. QuickTime's approach is to create a different file for each. This complicates the encoding process and does not address the issue of fluctuating bandwidths. However, having each file individually encoded does provide enormous flexibility.
RealNetwork's SureStream technology and Microsoft's Intelligent Streaming lets you put multiple tracks in a single file each with a different bit rate for delivery. Of the two Real's SureStream is the most sophisticated and flexible, and if bandwidth fluctuations are an important factor in delivery of content this will deal with it best. Combining SureStream with SMIL is also possible.
The content creator can either prepare media clips in advance or encode a live event as it happens. In this the term encoder refers to the software (such as RealProducer, for example) that converts live or pre-existing media into a format that the server can deliver.
