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Chapter 6. Tuning, Delivering, and Protecting Video Content

Chapter 6. Tuning, Delivering, and Protecting Video Content

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Figure 6-1. Video processing involves several steps, including demuxing and muxing



There are three main steps for turning source material of video and audio into a single

video file:

1. Demuxing: separates out video and audio streams

2. Encoding: compresses video and audio streams

3. Muxing: combines video and audio streams plus captions (if any)

Note that text transcription can optionally be converted into time-coded captions and

added into the mix to yield a single final video file during the step of muxing. There are

four main concepts in video encoding:

1.

2.

3.

4.



Video codec format: defines how pixels are compressed

Audio codec format: defines how waveforms are compressed

Caption format: defines if and when captions are displayed

Video container format: holds it all together (think about zip format)



The video container formats define how video and audio are packaged together and

they are commonly shown as the suffix of video files, therefore often referred to as video

formats. Popular container formats include AVI, MP4, OGG, and FLV. Each has its

own compatible audio and video codecs and caption formats, as detailed in the comparison found at http://goo.gl/G0q01.*



* Note that some codecs may be protected by patents or other intellectual property rights; you should get

appropriate legal advice and information to help you determine if you need to seek a license for any particular

codec.



74 | Chapter 6: Tuning, Delivering, and Protecting Video Content



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On Google TV, there are two options for serving video content with a web app:

1. Embed video using HTML5 in a web page in Google Chrome

2. Embed video using the Flash Player plug-in in Google Chrome

Next, let’s go over each one of these options and discuss specific recommendations in

terms of encoding codecs and container formats, as well as optimization and tuning

techniques.



Embedding Video with HTML5 in Google Chrome

Prior to the advent of HTML5, there was no standards-based way to achieve video

content delivery. Instead, video “on the web” typically was funneled through a third

party plug-in, such as QuickTime or Flash Player.

HTML5 introduced the