The reading notes record thoughts from things I read. 這網誌是我的一些閱讀後的思考和摘要記錄。My website 我的網頁:

HTML5, truce or war

The HTML Hypertext Markup Language is the basis of Internet today.  When it was first standardized in 1990, it mainly defined how the text, hypertext and image should be shown in a webpage by the browsers.  Different kinds of browsers in the markets were able to do more or less the same thing and webpages could be correctly viewed on different platforms as they were compatible with each other.  As multi-media became more and more popular, sound and video were being incorporated in webpages.  The pace of such advancement was so rapid that browser companies were unable to cope.  There were many third party companies coming into the market offering various types of software which could be added, or plugged-in, to a browser to enable it to play audio and video.  The Internet world was then in chaos with companies offering different technologies and file formats.  Browser companies and the Internet users found it very confusing and inconvenient where webpages were not correctly displayed all the time and media often not correctly played. 

You may have experienced the various types of music files and many different types of video files which required different devices or programs to run.  Same as the video tape format war many years ago, many companies are also at war promoting their own formats.  Music format war started early and the battles were on resolution, clarity, compactness with fans supporting different products.  Audiophiles like no compression or lossless compression files, while others like highly compressed file with very small size but acceptable sound quality.  For video, the battles were very intense.  You may have heard that Adobe Flash is trying to dominate the market while Steve Jobs refused to support it in Apple devices.

The latest version of HTML version 5 is meant to solve this problem.  The syntax of HTML5 has been rewritten to make the language more simple and streamlined.  Most importantly, it added the universal Audio and Video tags in the language so that all browsers could interpret them in the same way.  The most obvious benefit is that a truce is called among all browser companies.  They can all go and enhance their browsers to support HTML5 and the standard will be universal.  There will be better compatibility among browsers on all multi-media webpages.  On the other hand, you can guess that the third-party plug-in software companies will go out of business if they do not diversify, as audio and video plug-ins are no linger required.

The reaction in the content providers field is enthusiastic.  Steve Jobs commented that HTML5 is the best way forward for a multi-media Internet over Flash.  Adobe announced that it would no longer develop Flash for mobile devices.  Almost all major content providers are now upgrading to HTML5.  YouTube has already released a test version of HTML5 video playing.  In a few years time, users will migrate en masse to browsers that support HTML5.

However, the world is not as peaceful as we like it to be. While HTML5 defines the language standard of audio and video tags, it does not define which file formats should be used.  It is left to individual browser companies to decide which file formats are to be supported.  Judging from the experience of image file format, browsers would support all popular image file formats in use, as the program required to code and decode (codec) the popular file formats are readily available. But of course there are still some advanced image file formats not supported by any browser and cannot be displayed in webpages.

Sound and video files are more difficult as these dynamic and streaming data require more complicated codec.  Browser companies do not want to include many copies of different codec in their program.  They can only choose the most popular ones.   This choice triggered another file format war.

A very popular format today is the MPEG.  Its popular audio file is MP3 and video file is MP4.  You may think that most browsers would support these formats.  However, there is a hitch.  MPEG file formats are copyrighted.  The rights are owned by a consortium of which the stake holders include Microsoft and Apple.  Surely these companies will push for MPEG as the de facto standard.  But many companies which use open source codes are unwilling to pay the MPEG copyright fees.  They are the giants Google and Mozilla who adopted copyright-free audio and video file format of OGG.  The war at present comes to a stalemate where different browsers support their own file formats of choice.  It is really like the video tape war where there were different video tape players supporting VHS and Betamax.

The victims of this war are the content providers and the Internet users.  Much valuable contents are using different file formats and we cannot give up either one.  The solution is troublesome.  Notwithstanding the war and the different file formats used by different browsers, content provider companies encode several copies of an audio or video file in all popular formats.  The webpages are written in a way that any browser could detect the file format supported and choose the correct file to play.  This is for the benefit of users who do not have to worry about file formats.  The problem is that the media file libraries of the content providers are several times larger than needed.