swffileformat.html

flash文件的格式的详细的说明 flash文件的格式的详细的说明

    and in the place/move/remove model used by the display list.</li>
<li><span class="runInHead">Shape Data Structure&#151;</span>The shape data structure 
uses a unique structure to minimize the size of shapes and to render anti-aliased 
shapes very efficiently on the screen.</li>
</ul>

<p> Note that although the individual components of a SWF file are compressed, 
  there is no overall compression applied to the .swf file. This makes it possible 
  for a player to process the file structure directly out of RAM without decompressing 
  it. Various elements of the file such as bitmaps, shapes and sounds can be decompressed 
  as they are needed. </p>

<a name="h3ExtensionMechanism"> </a>
<h3>Extension Mechanism</h3>

<p>
In order to let applications define their own tag types, it is possible to define an AppExtension tag that contains the name of the application functionality being implemented and a tag range that describe what tags will be used by this extension set. The extension sets should be similar to a MIME type where they take the form of the following string:
</p>

<pre>
&lt;company name&gt;/&lt;extension set&gt;
</pre>


<p>
For the entire file, these tag types will be interpreted in the context of the named extension. Applications should be able to remap the tag range for a particular file to avoid conflicts between two extension sets.
</p>

<p>
The extension must be in the 512-1023 tag type range.
</p>

<a name="h2SampleSWFFiles"> </a>
<h2>Sample SWF Files</h2>

<p> The following section shows a SWF file. Syntax is displayed in monospaced 
  font. Explanations of the syntax appear in normal font. </p>


<pre>
***** Dumping SWF File Information *****
----- Reading the file header -----
FWS
File version    3
File size       741
Movie width     550
Movie height    400
Frame rate      12
Frame count     10
</pre>

<p> The file header shows much information. FWS indicates that the file is a SWF 
  file; its version is 3.0 file. The file size is 741 bytes. The movie width is 
  550; its height is 400 pixels. The frame rate is 12 frames per second; there 
  are ten frames in this movie. </p>

<pre>
----- Reading movie details -----
&lt;----- dumping frame 0        file offset 21       -----&gt;
</pre>

<p>
The offset of Frame 0 is 21 bytes into the file.
</p>

<pre>
tagLen        3: tagSetBackgroundColor  RGB_HEX ffffff
</pre>

<p>
TagLen specifies the actual length of the tag, in this case, 3 bytes (ffffff). .This tagSetBackgroundColor sets the background color to white.
</p>

<pre>
tagLen        2: tagDoAction
                 action code   7 stop
                 action code   0
</pre>

<p>
Pauses the frame. (DoAction's action is Stop. Action code 0 means that there are no more actions.)
</p>

<pre>
tagLen       32: tagDefineShape         tagid 1
</pre>

<p>
Defines the first shape.
</p>

<pre>
tagLen       10: tagPlaceObject2        flags 1     depth 26
                 tag 1
                 pos matrix hex [ a_fixed   b_fixed] = [00010000   00000000]
                                [ c_fixed   d_fixed]   [00000000   00010000]
                                [tx_fixed  ty_fixed]   [000010a4   00000410]
</pre>

<p>
Inserts the first shape (tag 1) on the display list. The object's position on the stage is defined by the matrix. 
</p>

<pre>
tagLen      201: tagDefineShape2        tagid 2
tagLen       76: tagDefineShape         tagid 3
tagLen      190: tagDefineShape2        tagid 4
tagLen       33: tagDefineButton2       tagid 5
</pre>

<p>
Defines more shapes and a button.
</p>

<pre>
tagLen       15: tagPlaceObject2        flags 2     depth 26
                 tag 5
                 pos matrix hex [ a_fixed   b_fixed] = [0004dbd3   00000000]
                                [ c_fixed   d_fixed]   [00000000   0004dbd3]
                                [tx_fixed  ty_fixed]   [00000600   00000a1c]
</pre>

<p>
Inserts the button (tag 5) on display list. 
</p>

<pre>
tagLen        0: tagShowFrame
</pre>

<p>
Displays contents of display list on the screen.
</p>

<pre>
&lt;----- dumping frame 1        file offset 627      -----&gt;
tagLen        2: tagRemoveObject2 depth 2
</pre>


<p>
Removes button from the display list.
</p>

<pre>
tagLen        8: tagPlaceObject2        flags 1     depth 26
                 pos matrix hex [ a_fixed   b_fixed] = [00010000   00000000]
                                [ c_fixed   d_fixed]   [00000000   00010000]
                                [tx_fixed  ty_fixed]   [000012ea   00000690]
</pre>

<p>
Moves square left to right, top to bottom, diagonally on the stage.  
</p>

<pre>
tagLen        0: tagShowFrame
</pre>

<p>
Displays display list contents on the screen.
</p>


<pre>
&lt;----- dumping frame 2        file offset 643      -----&gt;
tagLen        8: tagPlaceObject2        flags 1     depth 26
                 pos matrix hex [ a_fixed   b_fixed] = [00010000   00000000]
                                [ c_fixed   d_fixed]   [00000000   00010000]
                                [tx_fixed  ty_fixed]   [00001530   00000910]
</pre>

<p>
Moves square left to right, top to bottom, diagonally on the stage.  
</p>

<pre>
tagLen        0: tagShowFrame
</pre>


<p>
Displays contents of display list on the screen.
</p>

<pre>
&lt;----- dumping frame 3        file offset 655      -----&gt;
tagLen        8: tagPlaceObject2        flags 1     depth 26
                 pos matrix hex [ a_fixed   b_fixed] = [00010000   00000000]
                                [ c_fixed   d_fixed]   [00000000   00010000]
                                [tx_fixed  ty_fixed]   [00001776   00000b90]
</pre>

<p>
Moves square left to right, top to bottom, diagonally on the stage.  
</p>

<pre>
tagLen        0: tagShowFrame
</pre>

<p>
Displays contents of display list on the screen.
</p>

<pre>
&lt;----- dumping frame 4        file offset 667      -----&gt;
tagLen        8: tagPlaceObject2        flags 1     depth 26
                 pos matrix hex [ a_fixed   b_fixed] = [00010000   00000000]
                                [ c_fixed   d_fixed]   [00000000   00010000]
                                [tx_fixed  ty_fixed]   [000019bc   00000e10]
</pre>

<p>
Moves square left to right, top to bottom, diagonally on the stage.  
</p>

<pre>
tagLen        0: tagShowFrame
</pre>

<p>
Displays contents of display list on the screen.
</p>

<pre>
&lt;----- dumping frame 5        file offset 679      -----&gt;
tagLen        8: tagPlaceObject2        flags 1     depth 26
                 pos matrix hex [ a_fixed   b_fixed] = [00010000   00000000]
                                [ c_fixed   d_fixed]   [00000000   00010000]
                                [tx_fixed  ty_fixed]   [00001c03   00001090]
</pre>

<p>
Moves square left to right, top to bottom, diagonally on the stage.  
</p>

<pre>
tagLen        0: tagShowFrame
</pre>


<p>
Displays contents of display list on the screen.
</p>

<pre>
&lt;----- dumping frame 6        file offset 691      -----&gt;
tagLen        8: tagPlaceObject2        flags 1     depth 26
                 pos matrix hex [ a_fixed   b_fixed] = [00010000   00000000]
                                [ c_fixed   d_fixed]   [00000000   00010000]
                                [tx_fixed  ty_fixed]   [00001e49   00001310]
</pre>

<p>
Moves square left to right, top to bottom, diagonally on the stage.  
</p>

<pre>
tagLen        0: tagShowFrame
</pre>

<p>
Displays contents of display list on the screen.
</p>

<pre>
&lt;----- dumping frame 7        file offset 703      -----&gt;
tagLen        8: tagPlaceObject2        flags 1     depth 26
                 pos matrix hex [ a_fixed   b_fixed] = [00010000   00000000]
                                [ c_fixed   d_fixed]   [00000000   00010000]
                                [tx_fixed  ty_fixed]   [0000208f   00001590]
</pre>

<p>
Moves square left to right, top to bottom, diagonally on the stage.  
</p>


<pre>
tagLen        0: tagShowFrame
</pre>

<p>
Displays contents of display list on the screen.
</p>

<pre>
&lt;----- dumping frame 8        file offset 715      -----&gt;
tagLen        8: tagPlaceObject2        flags 1     depth 26
                 pos matrix hex [ a_fixed   b_fixed] = [00010000   00000000]
                                [ c_fixed   d_fixed]   [00000000   00010000]
                                [tx_fixed  ty_fixed]   [000022d5   00001810]
</pre>

<p>
Moves square left to right, top to bottom, diagonally on the stage.  
</p>

<pre>
tagLen        0: tagShowFrame
</pre>

<p>
Displays contents of display list on the screen.
</p>

<pre>
&lt;----- dumping frame 9        file offset 727      -----&gt;
tagLen        8: tagPlaceObject2        flags 1     depth 26
                 pos matrix hex [ a_fixed   b_fixed] = [00010000   00000000]
                                [ c_fixed   d_fixed]   [00000000   00010000]
                                [tx_fixed  ty_fixed]   [0000251b   00001a90]
</pre>

<p>
Moves square left to right, top to bottom, diagonally on the stage.  
</p>

<pre>
tagLen        0: tagShowFrame
</pre>

<p>
Displays contents of display list on the screen.
</p>

<pre>
&lt;----- dumping frame 10       file offset 739      -----&gt;
tagLen        0: tagEnd
</pre>


<p>
tagEnd indicates the end of the file.
</p>

<pre>
***** Finished Dumping SWF File Information *****
</pre>

<br>
<br>
<hr>
SWF File Format Specification<br>
<a href="SWFfilereference.html">SWF File Reference</a><br>
<a href="terminology.html">Terminology</a><br>
<hr>
<br>
<br>
</body>
</html>