diff --git a/trunk/conf/full.conf b/trunk/conf/full.conf
index dddecc20a..b06472438 100644
--- a/trunk/conf/full.conf
+++ b/trunk/conf/full.conf
@@ -563,6 +563,7 @@ vhost with-hls.srs.com {
         # whether use floor for the hls_ts_file path generation.
         # if on, use floor(timestamp/hls_fragment) as the variable [timestamp],
         #       and use enahanced algorithm to calc deviation for segment.
+        # @remark when floor on, recommend the hls_segment>=2*gop.
         # default: off
         hls_ts_floor    off;
         # the hls entry prefix, which is base url of ts url.
@@ -740,7 +741,8 @@ vhost hooks.callback.srs.com {
         #           "ip": "192.168.1.10", "vhost": "video.test.com", "app": "live",
         #           "stream": "livestream",
         #           "cwd": "/usr/local/srs",
-        #           "file": "./objs/nginx/html/live/livestream.1420254068776-100.ts"
+        #           "file": "./objs/nginx/html/live/livestream.1420254068776-100.ts",
+        #           "seq_no": 100
         #       }
         # if valid, the hook must return HTTP code 200(Stauts OK) and response
         # an int value specifies the error code(0 corresponding to success):
diff --git a/trunk/research/api-server/server.py b/trunk/research/api-server/server.py
index 5fcd0ea63..e8fbd0418 100755
--- a/trunk/research/api-server/server.py
+++ b/trunk/research/api-server/server.py
@@ -333,6 +333,99 @@ class RESTDvrs(object):
 
         return code
 
+'''
+handle the hls requests: hls stream.
+'''
+class RESTHls(object):
+    exposed = True
+
+    def GET(self):
+        enable_crossdomain()
+
+        hls = {}
+        return json.dumps(hls)
+
+    '''
+    for SRS hook: on_dvr, on_dvr_reap_segment
+    on_dvr:
+        when srs reap a dvr file, call the hook,
+        the request in the POST data string is a object encode by json:
+              {
+                  "action": "on_dvr",
+                  "client_id": 1985,
+                  "ip": "192.168.1.10", "vhost": "video.test.com", "app": "live",
+                  "stream": "livestream",
+                  "cwd": "/usr/local/srs",
+                  "file": "./objs/nginx/html/live/livestream.1420254068776.flv"
+              }
+    on_dvr_reap_segment:
+        when api dvr specifes the callback when reap flv segment, call the hook,
+        the request in the POST data string is a object encode by json:
+              {
+                  "action": "on_dvr_reap_segment",
+                  "client_id": 1985,
+                  "vhost": "video.test.com", "app": "live",
+                  "stream": "livestream",
+                  "cwd": "/usr/local/srs",
+                  "file": "./objs/nginx/html/live/livestream.1420254068776.flv"
+              }
+    if valid, the hook must return HTTP code 200(Stauts OK) and response
+    an int value specifies the error code(0 corresponding to success):
+          0
+    '''
+    def POST(self):
+        enable_crossdomain()
+
+        # return the error code in str
+        code = Error.success
+
+        req = cherrypy.request.body.read()
+        trace("post to dvrs, req=%s"%(req))
+        try:
+            json_req = json.loads(req)
+        except Exception, ex:
+            code = Error.system_parse_json
+            trace("parse the request to json failed, req=%s, ex=%s, code=%s"%(req, ex, code))
+            return str(code)
+
+        action = json_req["action"]
+        if action == "on_dvr":
+            code = self.__on_dvr(json_req)
+        if action == "on_dvr_reap_segment":
+            code = self.__on_dvr_reap_segment(json_req)
+        else:
+            trace("invalid request action: %s"%(json_req["action"]))
+            code = Error.request_invalid_action
+
+        return str(code)
+
+    def OPTIONS(self, *args, **kwargs):
+        enable_crossdomain()
+
+    def __on_dvr(self, req):
+        code = Error.success
+
+        trace("srs %s: client id=%s, ip=%s, vhost=%s, app=%s, stream=%s, cwd=%s, file=%s"%(
+            req["action"], req["client_id"], req["ip"], req["vhost"], req["app"], req["stream"],
+            req["cwd"], req["file"]
+        ))
+
+        # TODO: process the on_dvr event
+
+        return code
+
+    def __on_dvr_reap_segment(self, req):
+        code = Error.success
+
+        trace("srs %s: client id=%s, vhost=%s, app=%s, stream=%s, cwd=%s, file=%s"%(
+            req["action"], req["client_id"], req["vhost"], req["app"], req["stream"],
+            req["cwd"], req["file"]
+        ))
+
+        # TODO: process the on_dvr event
+
+        return code
+
 '''
 handle the sessions requests: client play/stop stream
 '''
@@ -1133,6 +1226,7 @@ class V1(object):
         self.streams = RESTStreams()
         self.sessions = RESTSessions()
         self.dvrs = RESTDvrs()
+        self.hls = RESTHls()
         self.chats = RESTChats()
         self.servers = RESTServers()
         self.nodes = RESTNodes()
diff --git a/trunk/src/app/srs_app_hls.cpp b/trunk/src/app/srs_app_hls.cpp
index 6f3a76c71..be838dd8f 100644
--- a/trunk/src/app/srs_app_hls.cpp
+++ b/trunk/src/app/srs_app_hls.cpp
@@ -331,17 +331,18 @@ int SrsHlsMuxer::segment_open(int64_t segment_start_dts)
     std::string ts_file = hls_ts_file;
     ts_file = srs_path_build_stream(ts_file, req->vhost, req->app, req->stream);
     if (hls_ts_floor) {
-        int64_t floor_ts = (int64_t)(srs_get_system_time_ms() / (1000 * hls_fragment));
+        // we always ensure the piece is increase one by one.
         std::stringstream ts_floor;
-        ts_floor << floor_ts;
+        ts_floor << (int64_t)(previous_floor_ts + 1);
         ts_file = srs_string_replace(ts_file, "[timestamp]", ts_floor.str());
         
         // dup/jmp detect for ts in floor mode.
+        int64_t floor_ts = (int64_t)(srs_get_system_time_ms() / (1000 * hls_fragment));
         if (previous_floor_ts && previous_floor_ts != floor_ts - 1) {
             srs_warn("hls: dup or jmp for floor ts, previous=%"PRId64", current=%"PRId64", ts=%s, deviation=%.2f",
                      previous_floor_ts, floor_ts, ts_file.c_str(), hls_fragment_deviation);
         }
-        previous_floor_ts = floor_ts;
+        previous_floor_ts++;
     }
     ts_file = srs_path_build_timestamp(ts_file);
     if (true) {