Skip to Main Content
HTML5: Up and Running
book

HTML5: Up and Running

by Mark Pilgrim
August 2010
Intermediate to advanced content levelIntermediate to advanced
222 pages
7h 12m
English
O'Reilly Media, Inc.
Content preview from HTML5: Up and Running

Audio Codecs

Unless you’re going to stick to films made before 1927 or so, you’re going to want an audio track in your video. Like video codecs, audio codecs are encoding algorithms, in this case used for audio streams. As with video codecs, there are lossy and lossless audio codecs. And like lossless video, lossless audio is really too big to put on the Web, so I’ll concentrate on lossy audio codecs.

Actually, we can narrow the focus even further, because there are different categories of lossy audio codecs. Audio is used in many places where video is not (telephony, for example), and there is an entire category of audio codecs optimized for encoding speech. You wouldn’t rip a music CD with these codecs, because the result would sound like a four-year-old singing into a speakerphone. But you would use them in an Asterisk PBX, because bandwidth is precious, and these codecs can compress human speech into a fraction of the size of general-purpose codecs. However, due to lack of support in both native browsers and third-party plug-ins, speech-optimized audio codecs never really took off on the Web. So I’ll concentrate on general-purpose lossy audio codecs.

As I mentioned in Video Codecs, when you “watch a video,” your computer is doing several things at once:

  1. Interpreting the container format

  2. Decoding the video stream

  3. Decoding the audio stream and sending the sound to your speakers

The audio codec specifies how to do #3—decoding the audio stream and turning it into digital waveforms that ...

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Start your free trial

You might also like

HTML5 in Action

HTML5 in Action

Greg Wanish, Rob Crowther, Joe Lennon, Charles Brindle
HTML5 Cookbook

HTML5 Cookbook

Christopher Schmitt, Kyle Simpson
AngularJS

AngularJS

Shyam Seshadri, Brad Green

Publisher Resources

ISBN: 9781449392154Errata Page