SMIL 2.0 Basics Tutorial

First, Introduction
With the mature and wide application of the flow technology, we have a deep understanding of its advantages. However, its shortcomings are gradually reflected. The emergence of the problem requires us to think of ways to solve it. The SMIL is put forward to solve the problem in current flow technology. Now let's take a closer look at smil.
1, SMIL resume
SMIL is synchronous Multimedia Integration language (Synchronized Multimedia integration Language) abbreviation, read smile (hehe, this word is good). It is a multimedia manipulation language defined by the 3W (World Wide Web Consortium) organization. The latest SMIL version is the August 2001 SMIL 2.0 version (the number of companies involved in setting up the standard, J Compaq, Gateway, IBM, Microsoft, RealNetworks, Oratrix, etc.). Too much, I can't even breathe!!! )。 SMIL is very similar to the syntax format of the HTML (Hypertext Transfer language) we use on our web pages. The latter mainly for the ordinary network media files for manipulation (text, pictures, sound, animation, video, mechanical piling), while the former manipulation of multimedia snippets (multimedia pieces of the organic, intelligent combination). J looks like this thing is really good!
2, the advantages of SMIL?
The Smil language is a set of well defined and very simple tags. It is used to specify when, where, and in what way the multimedia clips (the range of multimedia included: sound files, video files, animations, pictures, text, etc.) are played. Are you confused? J Let's take a look at the advantages of SMIL (a different place!) )：
For convenience, we refer to the work we want to accomplish as a demo (presentation).
(1) Avoid using a unified inclusion file format
Because our multimedia file format is very much, for example: sound like *.mp3, *.wav, *.ra and so on, video format is more surprising: *.mpg, *.avi, *.mov, *.rm and so on; the format of the picture is even more needless to say. J if we want to play directly on the local machine or use streaming playback on the network to play several files. Of course, we hope that we don't always have to open the file ourselves. Instead, play the next after the last file has finished playing. Playlists are a way to do this. However, if the format is different, and multiple pieces are required to play at the same time (for example, when a picture is displayed, there is a narration sound.) Pictures and sounds are two files), the only possible way to do this is to use media editing software to integrate these multimedia files into a single file. This must unify the use of a file format. If your source file (multiple multimedia snippets) does not have a copy, you will regret it the next time you want to use one of the source files. If we use SMIL to organize these multimedia files, we can get the results we want without making any changes to the source file (from here, Smil seems to be the golden thread of a pearl necklace, just put them together to form a whole, without breaking them.) )。 Of course the function of smil is by no means the point. Next is:
(2) Simultaneous playback of multimedia clips in different places (servers)
If you can do it in the 1th place, I'm afraid you won't be able to do it. Font face= "Wingdings" >j consider a practical question: if we now want to add a commentary (including audio commentary) to a TV interview (video file) and text narration). Let's assume that the video file in the example is a file on Server A, the audio file is B on the server, and the explanatory text is the C file on the server. The traditional approach is at the end of the tether (j), and Smil can do it very easily.
(3) Time control
If we don't want to use the entire video file, we want to use just one part of it. The only thing that works in traditional methods is to clip software. Take time and effort not to say, make bad is self-defeating, the want to cut off! And it's really easy for smil to do it! Look at an example: set the video file a length of time is 10 seconds, we want to use 2-5 seconds, the other parts we do not want, as long as the SMIL rules: in the second second of the video file a play, play to the end of the fifth seconds can be.
Another part of the time control is animation and transition effects. If the above time control is silk, then this is the double-sided embroidery on it! We will discuss the issue in detail later. J
(4) layout of the entire demo
Let's take the example mentioned above to illustrate the problem: as we have video and text, what kind of layout do we want? In general, play the video in one area (the upper part of the screen) and display the text (at the bottom of the screen) in another area. Of course, if you think it's better to show text on the video, that's OK. Using SMIL to achieve this effect is exceptionally easy!