如果利用php來判斷就簡單了,原理很簡單,識別是否是動畫,要檢查文件中是否包含chr(0×21).chr(0xff).chr(0x0b).’NETSCAPE2.0‘chr(0×21).chr(0xff),是gif圖片中擴展功能段的標頭‘NETSCAPE2.0‘是擴展功能執行的程序名,代碼如下。
- <?php
- function IsAnimatedGif($filename)
- {
- $fp = fopen($filename, 'rb');
- $filecontent = fread($fp, filesize($filename));
- fclose($fp);
- return strpos($filecontent,chr(0x21).chr(0xff).chr(0x0b).'NETSCAPE2.0') === FALSE?0:1;
- }
- echo IsAnimatedGif("test.gif");
- ?>
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