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java对GIF的编解码工具,有完整的说明和例子

                    <span class="code">
                    <font color="#ffffff">&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#7f0055"><b>public&nbsp;</b></font><font color="#000000">void&nbsp;addComment</font><font color="#000000">(</font><font color="#000000">String&nbsp;</font><font color="#000000">comment</font><font color="#000000">);</font><br/>
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<td bgcolor="#324697" align="center"class="white_large">Construct GIF Frames. Add GIF Frames to GIF Images. Absolute & Relative GIF Frame Positioning</td>
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              <a name="gifframecreate"></a><h1 align="center">Construct a GIF Frame</h1>
                    <p>
                    The <a href="java-api-light/com/gif4j/light/GifFrame.html" target="_blank">GifFrame</a> java class
                    is used as a container to aggregate and encode the gif format specific information about a single gif image frame.
                    </p>
                    <p style="margin-top: 10px;">
                        <a href="java-api-light/com/gif4j/light/GifFrame.html" target="_blank">GifFrame</a> constructors can be divided into 2 types according to the desired frame position (absolute or relative).
                        <i>"absolute positioning"</i> costructors contain <span class="code"><b>Point</b></span> parameter and
                        <i>"relative positioning"</i> constructors contain <span class="code"><b>layout constraint</b></span> parameter.<br>
                        <br class="small"><span class="text_red">Note</span>: If you use <i>"relative positioning"</i> then
                        the final position is calculated according to one of the predifined <span class="code"><b>layout constraint</b></span>
                         before the final encoding process starts.<br>
                        <br class="small"><a name="absrelpos"></a><h1 align="center">Absolute and Relative Internal GIF Frame Positioning</h1>
                        Below examples demostrate relative positioning and how you can use it (see <i>examples/FramePositioning</i>):<br><br>
                        <center>
                        <img border="1" src="images/tutorial/FramePositioningExample_relative_1.gif"><br>
                                        (size: 300x300, every frame size: 100x100)<br><br>
                        <img border="1" src="images/tutorial/FramePositioningExample_relative_2.gif"><br>
                                        (size: 200x200, every frame size: 100x100)<br><br>
                        <img border="1" src="images/tutorial/FramePositioningExample_relative_3.gif"><br>
                                        image tour (size: 300x240, every frame is scaled down using <a href="java-api-light/com/gif4j/light/ImageUtils.html" class="green" target="_blank">ImageUtils</a> to 150x130)<br><br>
                        </center>
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                 <a name="gifframedisposalmethoddelaytime"></a><h1 align="center">Disposal Methods & Delay Time</h1>
                 <p><b>Disposal Method</b> - indicates the way in which the graphic is to be treated after being displayed.
                According to Gif89a format specification there are 4 disposal methods:<br>
                <a href="java-api-light/com/gif4j/light/GifFrame.htmll#DISPOSAL_METHOD_NOT_SPECIFIED" target="_blank">Not Specified</a>,
                <a href="java-api-light/com/gif4j/light/GifFrame.htmll#DISPOSAL_METHOD_DO_NOT_DISPOSE" target="_blank">Do Not Dispose</a>,
                <a href="java-api-light/com/gif4j/light/GifFrame.htmll#DISPOSAL_METHOD_RESTORE_TO_BACKGROUND_COLOR" target="_blank">Restore To Background Color</a> and
                <a href="java-api-light/com/gif4j/light/GifFrame.htmll#DISPOSAL_METHOD_RESTORE_TO_PREVIOUS" target="_blank">Restore To Previous</a>.<br>
                <br class="small">You can set disposal method through corresponding <span class="code">GifFrame</span>
                constructors or using the next method:<br><br class="small">
                <span class="code">
                <font color="#ffffff">&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#7f0055"><b>public&nbsp;</b></font><font color="#7f0055"><b>void&nbsp;</b></font><font color="#000000">setDisposalMethod</font><font color="#000000">(</font><font color="#7f0055"><b>int&nbsp;</b></font><font color="#000000">disposalMethod</font><font color="#000000">)&nbsp;</font><br/>
                </span>
                <br>
                 <b>Delay Time</b> - If not 0, this field specifies the number of
                 hundredths (1/100) of a second to wait before continuing with the
                 processing of the Data Stream. The clock starts ticking immediately
                 after the graphic is rendered.<br><br class="small">
                You can set delay time through corresponding <span class="code">GifFrame</span>
                constructors or using the next method:<br><br class="small">
                <span class="code">
                <font color="#ffffff">&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#7f0055"><b>public&nbsp;</b></font><font color="#7f0055"><b>void&nbsp;</b></font><font color="#000000">setDelay</font><font color="#000000">(</font><font color="#7f0055"><b>int&nbsp;</b></font><font color="#000000">delay</font><font color="#000000">)&nbsp;</font><br/>
                </span>
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                 <br class="small"><a name="gifframeadd"></a><h1 align="center">Adding GIF Frames to a GIF Image</h1>
                 <p>To add <span class="code">GifFrame</span>(s) to <span class="code">GifImage</span>(s)
                    you can use the next method (please consult <a href="java-api-light/com/gif4j/light/GifFrame.html" class="green" target="_blank">GifFrame</a> API for more information):<br><br class="small">
                    <span class="code">
                    <font color="#ffffff">&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#7f0055"><b>public&nbsp;</b></font><font color="#000000">GifImage&nbsp;addGifFrame</font><font color="#000000">(</font><font color="#000000">GifFrame&nbsp;frame</font><font color="#000000">)</font><br/>
                    </span>
                    <br>
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<td bgcolor="#324697" align="center"class="white_large">Encode and Save GIF Images</td>
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     <a name="gifimagewrite"></a><h1 align="center">Encode and Save a GIF Image</h1>
                    <p>
                    The <a href="java-api-light/com/gif4j/light/GifEncoder.html" target="_blank">GifEncoder</a> java class
                    lets programmers encode and save images out to a file or output stream
                    using the GIF file format (GIF89a version) with a single method call.
                    The next methods to encode and save images as GIFs are available (please consult the <a href="java-api-light/com/gif4j/light/GifEncoder.html" target="_blank">Gif4J LIGHT Java API</a> for more info):<br>
                    <br class="small">
                    <font color="#ffffff">&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#7f0055"><b>public&nbsp;static&nbsp;final&nbsp;</b></font><font color="#7f0055"><b>void&nbsp;</b></font><font color="#000000">encode</font><font color="#000000">(</font><font color="#000000">Image&nbsp;image,&nbsp;DataOutput&nbsp;dataOutput</font><font color="#000000">)</font><br/>
                    <font color="#ffffff">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#7f0055"><b>throws&nbsp;</b></font><font color="#000000">IOException;</font><br/>
                    <br class="small">
                    <font color="#ffffff">&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#7f0055"><b>public&nbsp;static&nbsp;final&nbsp;</b></font><font color="#7f0055"><b>void&nbsp;</b></font><font color="#000000">encode</font><font color="#000000">(</font><font color="#000000">Image&nbsp;image,&nbsp;File&nbsp;output</font><font color="#000000">)</font><br/>
                    <font color="#ffffff">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#7f0055"><b>throws&nbsp;</b></font><font color="#000000">IOException;</font><br/>
                    <br class="small">
                    <font color="#ffffff">&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#7f0055"><b>public&nbsp;static&nbsp;final&nbsp;</b></font><font color="#7f0055"><b>void&nbsp;</b></font><font color="#000000">encode</font><font color="#000000">(</font><font color="#000000">Image&nbsp;image,&nbsp;OutputStream&nbsp;outputStream</font><font color="#000000">)</font><br/>
                    <font color="#ffffff">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#7f0055"><b>throws&nbsp;</b></font><font color="#000000">IOException;</font><br/>
                    <br class="small">
                    <font color="#ffffff">&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#7f0055"><b>public&nbsp;static&nbsp;final&nbsp;</b></font><font color="#7f0055"><b>void&nbsp;</b></font><font color="#000000">encode</font><font color="#000000">(</font><font color="#000000">GifImage&nbsp;gifImage,&nbsp;File&nbsp;output</font><font color="#000000">)</font><br/>