diff --git a/trunk/src/app/srs_app_rtp.cpp b/trunk/src/app/srs_app_rtp.cpp
index 7acbab24d..de01bc54f 100644
--- a/trunk/src/app/srs_app_rtp.cpp
+++ b/trunk/src/app/srs_app_rtp.cpp
@@ -67,6 +67,8 @@ srs_error_t SrsRtpMuxer::frame_to_packet(SrsSharedPtrMessage* shared_frame, SrsF
     if (format->is_avc_sequence_header()) {
         sps.assign(format->vcodec->sequenceParameterSetNALUnit.data(), format->vcodec->sequenceParameterSetNALUnit.size());
         pps.assign(format->vcodec->pictureParameterSetNALUnit.data(), format->vcodec->pictureParameterSetNALUnit.size());
+        // only collect SPS/PPS.
+        return err;
     }
 
     vector<SrsRtpSharedPacket*> rtp_packet_vec;
@@ -77,12 +79,6 @@ srs_error_t SrsRtpMuxer::frame_to_packet(SrsSharedPtrMessage* shared_frame, SrsF
         uint8_t header = sample.bytes[0];
         uint8_t nal_type = header & kNalTypeMask;
 
-        // TODO: FIXME: Magic number? Doc?
-        // ignore SEI nal
-        if (nal_type == 0x06 || nal_type == 0x09) {
-            continue;
-        }
-
         if (sample.size <= max_payload_size) {
             if ((err = packet_single_nalu(shared_frame, format, &sample, rtp_packet_vec)) != srs_success) {
                 return srs_error_wrap(err, "packet single nalu");
@@ -94,6 +90,14 @@ srs_error_t SrsRtpMuxer::frame_to_packet(SrsSharedPtrMessage* shared_frame, SrsF
         }
     }
 
+    if (! rtp_packet_vec.empty()) {
+        // At the end of the frame, set marker bit.
+        // One frame may have multi nals. Set the marker bit in the last nal end, no the end of the nal.
+        if ((err = rtp_packet_vec.back()->set_marker(true)) != srs_success) {
+            return srs_error_wrap(err, "set marker");
+        }
+    }
+
     shared_frame->set_rtp_packets(rtp_packet_vec);
 
     return err;
@@ -125,11 +129,7 @@ srs_error_t SrsRtpMuxer::packet_fu_a(SrsSharedPtrMessage* shared_frame, SrsForma
         // v=2,p=0,x=0,cc=0
         stream->write_1bytes(0x80);
         // marker payloadtype
-        if (i == num_of_packet - 1) {
-            stream->write_1bytes(kMarker | kH264PayloadType);
-        } else {
-            stream->write_1bytes(kH264PayloadType);
-        }
+        stream->write_1bytes(kH264PayloadType);
         // sequence
         stream->write_2bytes(sequence);
         // timestamp
@@ -183,7 +183,7 @@ srs_error_t SrsRtpMuxer::packet_single_nalu(SrsSharedPtrMessage* shared_frame, S
     // v=2,p=0,x=0,cc=0
     stream->write_1bytes(0x80);
     // marker payloadtype
-    stream->write_1bytes(kMarker | kH264PayloadType);
+    stream->write_1bytes(kH264PayloadType);
     // sequenct
     stream->write_2bytes(sequence);
     // timestamp
@@ -219,7 +219,7 @@ srs_error_t SrsRtpMuxer::packet_stap_a(const string &sps, const string& pps, Srs
     // v=2,p=0,x=0,cc=0
     stream->write_1bytes(0x80);
     // marker payloadtype
-    stream->write_1bytes(kMarker | kH264PayloadType);
+    stream->write_1bytes(kH264PayloadType);
     // sequenct
     stream->write_2bytes(sequence);
     // timestamp
diff --git a/trunk/src/app/srs_app_rtp.hpp b/trunk/src/app/srs_app_rtp.hpp
index badfea443..212bf776c 100644
--- a/trunk/src/app/srs_app_rtp.hpp
+++ b/trunk/src/app/srs_app_rtp.hpp
@@ -40,7 +40,6 @@ class SrsOriginHub;
 const int max_payload_size = 1200;
 const int kRtpPacketSize = 1500;
 
-const uint8_t kMarker = 0x80;
 const uint8_t kH264PayloadType = 102;
 
 const uint8_t kNalTypeMask = 0x1F;
diff --git a/trunk/src/app/srs_app_utility.cpp b/trunk/src/app/srs_app_utility.cpp
index 2cbd0aeeb..754aa34f1 100644
--- a/trunk/src/app/srs_app_utility.cpp
+++ b/trunk/src/app/srs_app_utility.cpp
@@ -1201,7 +1201,6 @@ string srs_string_dumps_hex(const std::string& str, const int& limit)
 string srs_string_dumps_hex(const char* buf, const int length, const int& limit)
 {
     string ret;
-    ret.reserve(limit * 4);
 
     char tmp_buf[1024*16];
     tmp_buf[0] = '\n';
diff --git a/trunk/src/kernel/srs_kernel_rtp.cpp b/trunk/src/kernel/srs_kernel_rtp.cpp
index 516ae89ff..414b2aad1 100644
--- a/trunk/src/kernel/srs_kernel_rtp.cpp
+++ b/trunk/src/kernel/srs_kernel_rtp.cpp
@@ -110,3 +110,19 @@ SrsRtpSharedPacket* SrsRtpSharedPacket::copy()
 
     return copy;
 }
+
+srs_error_t SrsRtpSharedPacket::set_marker(bool marker)
+{
+    srs_error_t err = srs_success;
+    if (payload_ptr == NULL || payload_ptr->payload == NULL || payload_ptr->size < 1) {
+        return srs_error_new(ERROR_RTC_RTP_MUXER, "rtp payload incorrect");
+    }
+
+    if (marker) {
+        payload_ptr->payload[1] |= kMarker;
+    } else {
+        payload_ptr->payload[1] &= (~kMarker);
+    }
+
+    return err;
+}
diff --git a/trunk/src/kernel/srs_kernel_rtp.hpp b/trunk/src/kernel/srs_kernel_rtp.hpp
index b348946ec..1de2269f3 100644
--- a/trunk/src/kernel/srs_kernel_rtp.hpp
+++ b/trunk/src/kernel/srs_kernel_rtp.hpp
@@ -28,6 +28,8 @@
 
 #include <string>
 
+const uint8_t kMarker = 0x80;
+
 class SrsRtpSharedPacket
 {
 private:
@@ -57,6 +59,9 @@ public:
 public:
     srs_error_t create(int64_t t, uint16_t seq, uint32_t sc, uint16_t pt, char* p, int s);
     SrsRtpSharedPacket* copy();
+// interface to modify rtp header
+public:
+    srs_error_t set_marker(bool marker);
 };
 
 #endif