Information Technology Reference
In-Depth Information
Codecs
Just like we did with audio, video must be encoded into one of a few formats that the
native Android web browser supports (mentioned subsequently). Encoding video can be
a bit trickier than audio in that you're encoding two things—namely the audio and the
video! We'll walk through the formats you can use, and discuss how to move audio and
video between them with ease.
h.264/MPEG-4
Over the years, MPEG-4 has become one of the premiere standards in video encoding
on the Internet and in our daily consumer lives, especially when it comes to high
definition video. Recently, MPEG-4 has come into the public consciousness through
the rise of social video sharing sites like YouTube and Vimeo, which allow users to
upload videos in this format. The current version of MPEG-4 is properly known as
h.264/MPEG-4 AVC, and is the standard for high quality video compression, such as
that found on a Blu-ray disc.
Ogg Theora
Theora is a free and open source lossy video compression format created by the same
foundation responsible for maintaining the Ogg audio codec, Xiph. Org Foundation.
While Theora itself is based on a proprietary video codec called VP3, it was later
released into the public domain, making it free for anyone to use as of March 2002.
Ogg Theora is similar in design to MPEG-4 and has quickly been progressing as a
technology over the last several years. While it is still not as comparable in quality to
MPEG-4 video, it is so close that a lot of developers who previously preferred the wide
acceptance of MPEG-4 now opting to go the HTML5 video route have started jumping
onto the Theora bandwagon.
WebM
A new contender in the video world is Google's very own WebM video codec.
Announced at the Google I/O conference in 2010, WebM is a royalty free video codec
that Google put out there in the wild to try and circumvent a lot of the problems that
were popping up in the HTML5 audio and video. While everyone is excited to use these
new technologies in their web applications and web sites, it is hard to do so without all
of the browser makers agreeing on a standard.
WebM is completely royalty free, which means that anyone can pick up the technology
and include it with their web browser without worrying about Google knocking on their
door in the future demanding a payout. Recall, though, that this refers to the
technology—not the actual content. Distributing copyrighted movies will get others to
knock on your door demanding a payout!
