diff --git a/lib/DirScanner.php b/lib/DirScanner.php
index 52d3a63..d5b60df 100644
--- a/lib/DirScanner.php
+++ b/lib/DirScanner.php
@@ -30,6 +30,7 @@ Class DirScanner {
         'snapshot' => '快照图片',
     ];
     private $rootDir;                               //当前扫描的根目录
+    private $webRoot = '/content/';                 //网站静态文件相对路径的根目录
     private $scanningDirLevel = 0;                  //当前扫描的目录深度
     private $scanStartTime = 0;                     //扫描开始时间，单位：秒
     private $scanResults = [];                      //目录扫描结果
@@ -101,7 +102,11 @@ Class DirScanner {
     }
 
     //根据文件路径生成唯一编号
+    //使用相对路径计算md5值
     private function getId($realpath) {
+        if (!empty($this->rootDir)) {
+            $realpath = str_replace($this->rootDir, '', $realpath);
+        }
         return !empty($realpath) ? md5($realpath) : '';
     }
 
@@ -276,17 +281,18 @@ Class DirScanner {
             $directory = "/{$directory}";
         }
 
+        $webRoot = preg_replace('/\/$/', '', $this->webRoot);
         $extensionPathMap = [                  //默认每种文件读取内容最大大小
             'txt' => '',
             'md' => '/view/',
             'url' => '/link/',
             'm3u8' => '/m3u8/',
-            'jpg' => "{$directory}{$filename}.{$extension}",
-            'png' => "{$directory}{$filename}.{$extension}",
-            'gif' => "{$directory}{$filename}.{$extension}",
-            'ico' => "{$directory}{$filename}.{$extension}",
-            'mp4' => "{$directory}{$filename}.{$extension}",
-            'ts' => "{$directory}{$filename}.{$extension}",
+            'jpg' => "{$webRoot}{$directory}{$filename}.{$extension}",
+            'png' => "{$webRoot}{$directory}{$filename}.{$extension}",
+            'gif' => "{$webRoot}{$directory}{$filename}.{$extension}",
+            'ico' => "{$webRoot}{$directory}{$filename}.{$extension}",
+            'mp4' => "{$webRoot}{$directory}{$filename}.{$extension}",
+            'ts' => "{$webRoot}{$directory}{$filename}.{$extension}",
         ];
 
         $path = isset($extensionPathMap[$extension]) ? $extensionPathMap[$extension] : '';
@@ -409,6 +415,24 @@ Class DirScanner {
         return $this->nginxSecureTimeout;
     }
 
+    //设置网站静态文件相对根目录
+    public function setWebRoot($webRoot) {
+        if (!empty($webRoot) && !preg_match('/^\//', $webRoot)) {
+            $webRoot = "/{$webRoot}";
+        }
+
+        if (!empty($webRoot) && !preg_match('/\/$/', $webRoot)) {
+            $webRoot = "{$webRoot}/";
+        }
+
+        $this->webRoot = $webRoot;
+    }
+
+    //获取网站静态文件相对根目录
+    public function getWebRoot() {
+        return $this->webRoot;
+    }
+
     //获取是否开启防盗链
     public function isSecureOn() {
         return $this->nginxSecureOn;
diff --git a/test/DirScannerTest.php b/test/DirScannerTest.php
index 3d54568..0d76220 100644
--- a/test/DirScannerTest.php
+++ b/test/DirScannerTest.php
@@ -66,6 +66,7 @@ $scanner = new DirScannerTest();
 
 //$dirTree = $scanner->scan('./');
 //$dirTree = $scanner->scan(__DIR__);
+$scanner->setWebRoot('/content/');
 $dirTree = $scanner->scan(__DIR__ . '/content/', 4);
 echo "Time cost: {$scanner->scanTimeCost} ms\n";
 echo "\n";