Introduction to video transcoding for CE

• Data -- the PC via modems (traditionally POTS, trend has been DSL and cable modem).
• Voice -- the telephone via wired and wireless.
• Video -- the TV with content provided by video cassette recorders (VCRs), DVD players, and cable or satellite set top boxes (STBs).

However today these services are accessed by the consumer through a diverse range of products in a variety of different ways. Figure 1 provides an illustration of the growth of some of the more common products in the home.

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Figure 1: The home of today/tomorrow

Many of the more recent devices, even the portables, are providing the full triple play of services. And with the growth of the PCs and portable devices, there have been a huge number of new applications that have become commonplace in the home. Some examples include multiplayer gaming, true video-on-demand (VOD), iTunes, social networking (MySpace), video sharing (YouTube), and video home editing. Figure 2 provides an illustration of how many of these applications are being used in the home.

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Figure 2: AV media applications in the home

And with the introduction of AV portable devices, a new era of AV media content is arriving. It's no longer just a dedicated device such as a STB providing only one type of service; broadcast analog and digital (MPEG-2) TV in the home. It is turning into many devices: personal data assistants (PDAs), portable media players (PMPs), digital video recorders (DVRs), digital media adapters (DMAs), video cell phones, etc. with many different types of services, and applications being made available to the consumer with a broad range of content (i.e., MPEG-2, MPEG-4 Simple Profile (SP), H.264, VC-1, On2, DivX). With the consumer, content is becoming king, and they want it anywhere, any time, and on any device. Figure 3 provides an illustration of some of the more popular AV "on the go" applications.

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Figure 3: AV portable media "on the go" applications

For the home, the living room is still the primary location where AV media content enters. But it's not just via the typical cable/satellite services anymore. The internet and cellular networks are also being used to access AV media and it is being accessed and viewed all over the home, not just in the living room. Figure 4 provides an example illustration where we see content being viewed and accessed in separate bedrooms, dens, and even from the car.

With AV media content as king, the consumer wants to easily move the content from device to device depending on the location where it will be used and be able to do this quickly at no additional cost, often in real-time or even faster than real-time. In this dynamic ever changing environment, the devices available to the consumer, which are many, must be able to exchange the content that is stored or viewed on them such that they can be viewed on alternative devices at different times by potentially a different consumer, all within the confines of the home originally, but eventually taken outside the home.


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Figure 4: Consumer AV media devices in the home

In making this a reality, there will be three necessary functions that will need to be supported. The first and most obvious is transcoding. Traditionally, transcoding has referred to the coding and recoding of digital AV content from one compressed format to another in order to allow for the transmission and playback by various devices. This becomes increasingly important as HD video is more widely available and viewed by the consumer. Over time, HD will become more of a necessity instead of a luxury. This will create a dichotomy in the home where the older or less capable devices will not be able to access it, which will further increase the need for transcoding. Many devices, especially portables, will not have the processing power or display capability to process the HD content. Hence the content will have to be transcoded to a different compression format or scaled to a lower image size, bit rate, and possible frame rate in order for the portable devices to process it.

Next: 3 Transcoding Types, A/V Container Formats and Network Protocols