diff --git a/trunk/conf/full.conf b/trunk/conf/full.conf
index a8b377749..9d106768a 100644
--- a/trunk/conf/full.conf
+++ b/trunk/conf/full.conf
@@ -754,6 +754,7 @@ vhost hooks.callback.srs.com {
         #           "client_id": 1985,
         #           "ip": "192.168.1.10", "vhost": "video.test.com", "app": "live",
         #           "stream": "livestream",
+        #           "duration": 9.36, // in seconds
         #           "cwd": "/usr/local/srs",
         #           "file": "./objs/nginx/html/live/livestream.1420254068776-100.ts",
         #           "seq_no": 100
diff --git a/trunk/research/api-server/server.py b/trunk/research/api-server/server.py
index 0c7d900f9..047718f86 100755
--- a/trunk/research/api-server/server.py
+++ b/trunk/research/api-server/server.py
@@ -328,8 +328,11 @@ class RESTHls(object):
               {
                   "action": "on_dvr",
                   "client_id": 1985,
-                  "ip": "192.168.1.10", "vhost": "video.test.com", "app": "live",
+                  "ip": "192.168.1.10", 
+                  "vhost": "video.test.com", 
+                  "app": "live",
                   "stream": "livestream",
+                  "duration": 9.68, // in seconds
                   "cwd": "/usr/local/srs",
                   "file": "./objs/nginx/html/live/livestream.1420254068776-100.ts",
                   "seq_no": 100
@@ -368,8 +371,8 @@ class RESTHls(object):
     def __on_hls(self, req):
         code = Error.success
 
-        trace("srs %s: client id=%s, ip=%s, vhost=%s, app=%s, stream=%s, cwd=%s, file=%s, seq_no=%s"%(
-            req["action"], req["client_id"], req["ip"], req["vhost"], req["app"], req["stream"],
+        trace("srs %s: client id=%s, ip=%s, vhost=%s, app=%s, stream=%s, duration=%s, cwd=%s, file=%s, seq_no=%s"%(
+            req["action"], req["client_id"], req["ip"], req["vhost"], req["app"], req["stream"], req["duration"],
             req["cwd"], req["file"], req["seq_no"]
         ))
 
diff --git a/trunk/src/app/srs_app_hls.cpp b/trunk/src/app/srs_app_hls.cpp
index e3caaa2be..7d064720a 100644
--- a/trunk/src/app/srs_app_hls.cpp
+++ b/trunk/src/app/srs_app_hls.cpp
@@ -170,11 +170,12 @@ void SrsHlsSegment::update_duration(int64_t current_frame_dts)
     return;
 }
 
-SrsDvrAsyncCallOnHls::SrsDvrAsyncCallOnHls(SrsRequest* r, string p, int s)
+SrsDvrAsyncCallOnHls::SrsDvrAsyncCallOnHls(SrsRequest* r, string p, int s, double d)
 {
     req = r;
     path = p;
     seq_no = s;
+    duration = d;
 }
 
 SrsDvrAsyncCallOnHls::~SrsDvrAsyncCallOnHls()
@@ -199,7 +200,7 @@ int SrsDvrAsyncCallOnHls::call()
         int sn = seq_no;
         for (int i = 0; i < (int)on_hls->args.size(); i++) {
             std::string url = on_hls->args.at(i);
-            if ((ret = SrsHttpHooks::on_hls(url, req, file, sn)) != ERROR_SUCCESS) {
+            if ((ret = SrsHttpHooks::on_hls(url, req, file, sn, duration)) != ERROR_SUCCESS) {
                 srs_error("hook client on_hls failed. url=%s, ret=%d", url.c_str(), ret);
                 return ret;
             }
diff --git a/trunk/src/app/srs_app_hls.hpp b/trunk/src/app/srs_app_hls.hpp
index 5bb54280a..e0d17e8f3 100644
--- a/trunk/src/app/srs_app_hls.hpp
+++ b/trunk/src/app/srs_app_hls.hpp
@@ -164,8 +164,9 @@ private:
     std::string path;
     int seq_no;
     SrsRequest* req;
+    double duration;
 public:
-    SrsDvrAsyncCallOnHls(SrsRequest* r, std::string p, int s);
+    SrsDvrAsyncCallOnHls(SrsRequest* r, std::string p, int s, double d);
     virtual ~SrsDvrAsyncCallOnHls();
 public:
     virtual int call();
diff --git a/trunk/src/app/srs_app_http_hooks.cpp b/trunk/src/app/srs_app_http_hooks.cpp
index 618de8ebb..6c717a29e 100644
--- a/trunk/src/app/srs_app_http_hooks.cpp
+++ b/trunk/src/app/srs_app_http_hooks.cpp
@@ -287,7 +287,7 @@ int SrsHttpHooks::on_dvr(string url, SrsRequest* req, string file)
     return ret;
 }
 
-int SrsHttpHooks::on_hls(string url, SrsRequest* req, string file, int sn)
+int SrsHttpHooks::on_hls(string url, SrsRequest* req, string file, int sn, double duration)
 {
     int ret = ERROR_SUCCESS;
     
@@ -302,6 +302,7 @@ int SrsHttpHooks::on_hls(string url, SrsRequest* req, string file, int sn)
         << SRS_JFIELD_STR("vhost", req->vhost) << SRS_JFIELD_CONT
         << SRS_JFIELD_STR("app", req->app) << SRS_JFIELD_CONT
         << SRS_JFIELD_STR("stream", req->stream) << SRS_JFIELD_CONT
+        << SRS_JFIELD_ORG("duration", duration) << SRS_JFIELD_CONT
         << SRS_JFIELD_STR("cwd", cwd) << SRS_JFIELD_CONT
         << SRS_JFIELD_STR("file", file) << SRS_JFIELD_CONT
         << SRS_JFIELD_ORG("seq_no", sn)
diff --git a/trunk/src/app/srs_app_http_hooks.hpp b/trunk/src/app/srs_app_http_hooks.hpp
index de64bef29..70a870f0a 100644
--- a/trunk/src/app/srs_app_http_hooks.hpp
+++ b/trunk/src/app/srs_app_http_hooks.hpp
@@ -102,8 +102,9 @@ public:
     *         ignore if empty.
     * @param file the ts file path, can be relative or absolute path.
     * @param sn the seq_no, the sequence number of ts in hls/m3u8.
+    * @param duration the segment duration in seconds.
     */
-    static int on_hls(std::string url, SrsRequest* req, std::string file, int sn);
+    static int on_hls(std::string url, SrsRequest* req, std::string file, int sn, double duration);
 private:
     static int do_post(std::string url, std::string req, int& code, std::string& res);
 };