diff --git a/trunk/research/ts_info.cc b/trunk/research/ts_info.cc
index eab6fbe96..dfe682428 100644
--- a/trunk/research/ts_info.cc
+++ b/trunk/research/ts_info.cc
@@ -585,6 +585,7 @@ public:
 	
 	int64_t pts; // 33bits
 	int64_t dts; // 33bits
+    int64_t pcr;
     
     // header size.
     int packet_header_size;
@@ -596,6 +597,10 @@ public:
 	int packet_data_size;
 	char* packet_data;
 	
+	// for avc.
+	u_int8_t nal_ref_idc;
+	u_int8_t nal_unit_type;
+	
 	TSMessage();
 	virtual ~TSMessage();
 	
@@ -709,12 +714,15 @@ TSMessage::TSMessage()
 	stream_type = TSStreamTypeReserved;
 	stream_id = 0;
 	packet_start_code_prefix = 0;
-	pts = dts = 0;
+	pts = dts = pcr = 0;
 	PES_packet_length = 0;
 	packet_header_size = 0;
 	parsed_packet_size = 0;
 	packet_data_size = 0;
 	packet_data = NULL;
+	
+	nal_ref_idc = 0;
+	nal_unit_type = 0;
 }
 
 TSMessage::~TSMessage()
@@ -1596,6 +1604,10 @@ int TSPayload::demux(TSContext* ctx, TSPacket* pkt, u_int8_t* start, u_int8_t* l
     }
     if (pid && (pid->type == TSPidTypeVideo || pid->type == TSPidTypeAudio)) {
 	    TSMessage* msg = ctx->get_msg(pkt->header->pid);
+
+		if (pkt->adaption_field->pcr > 0) {
+			msg->pcr = pkt->adaption_field->pcr;
+		}
 	    
         // flush previous PES_packet_length(0) packets.
         if (msg->packet_start_code_prefix == 0x01 
@@ -2135,6 +2147,10 @@ int consume(TSMessage* msg, AacMuxer* aac_muxer)
 		    int8_t nal_unit_type = *pp++;
 		    int8_t nal_ref_idc = (nal_unit_type >> 5) & 0x03;
 		    nal_unit_type &= 0x1f;
+		    
+		    msg->nal_ref_idc = nal_ref_idc;
+		    msg->nal_unit_type = nal_unit_type;
+		    
 		    if (nal_ref_idc != 0) {
 		        trace("ts+h264 got an SPS or PPS.");
 		    }
@@ -2235,6 +2251,18 @@ int main(int argc, char** argv)
 	            return -1;
 	        }
 	        
+	        int64_t pts = msg->pts;
+	        int64_t dts = (msg->dts == 0)? msg->pts : msg->dts;
+	        int64_t pcr = msg->pcr;
+	        static int64_t last_pcr_dts = 0;
+	        trace("demuxer+report id=%d, type=%s, size=%d, dts=%d, pts=%d, cts=%d, pcr=%d, dts-pcr=%d, ref=%d, unit=%d, dts(diff-pcr)=%d",
+	        	ctx.ts_packet_count, (msg->type == TSPidTypeVideo)? "video":"audio", 
+				msg->parsed_packet_size, dts, pts, pts - dts, pcr, pcr? dts - pcr : 0,
+				msg->nal_ref_idc, msg->nal_unit_type, pcr? dts - last_pcr_dts: 0);
+			if (pcr > 0) {
+				last_pcr_dts = dts;
+			}
+	        
 	        srs_freep(msg);
         }
     }
diff --git a/trunk/src/core/srs_core_codec.cpp b/trunk/src/core/srs_core_codec.cpp
index fb15c9331..88b270092 100644
--- a/trunk/src/core/srs_core_codec.cpp
+++ b/trunk/src/core/srs_core_codec.cpp
@@ -115,6 +115,10 @@ SrsCodec::SrsCodec()
 	avc_extra_data 			= NULL;
 	aac_extra_size 			= 0;
 	aac_extra_data 			= NULL;
+	sequenceParameterSetLength = 0;
+	sequenceParameterSetNALUnit = NULL;
+	pictureParameterSetLength = 0;
+	pictureParameterSetNALUnit = NULL;
 
 	stream = new SrsStream();
 }
@@ -125,6 +129,8 @@ SrsCodec::~SrsCodec()
 	srs_freepa(aac_extra_data);
 
 	srs_freep(stream);
+	srs_freepa(sequenceParameterSetNALUnit);
+	srs_freepa(pictureParameterSetNALUnit);
 }
 
 int SrsCodec::audio_aac_demux(int8_t* data, int size, SrsCodecSample* sample)
@@ -315,16 +321,67 @@ int SrsCodec::video_avc_demux(int8_t* data, int size, SrsCodecSample* sample)
 		int8_t lengthSizeMinusOne = stream->read_1bytes();
 		lengthSizeMinusOne &= 0x03;
 		NAL_unit_length = lengthSizeMinusOne;
-		/**
-		* skip the following:
-		* numOfSequenceParameterSets
-		* donot parse the following:
-		* sequenceParameterSetLength
-		* sequenceParameterSetNALUnit
-		* numOfPictureParameterSets
-		* pictureParameterSetLength
-		* pictureParameterSetNALUnit
-		*/
+		
+		// 1 sps
+		if (!stream->require(1)) {
+			ret = ERROR_HLS_DECODE_ERROR;
+			srs_error("hls decode video avc sequenc header sps failed. ret=%d", ret);
+			return ret;
+		}
+		int8_t numOfSequenceParameterSets = stream->read_1bytes();
+		numOfSequenceParameterSets &= 0x1f;
+		if (numOfSequenceParameterSets != 1) {
+			ret = ERROR_HLS_DECODE_ERROR;
+			srs_error("hls decode video avc sequenc header sps failed. ret=%d", ret);
+			return ret;
+		}
+		if (!stream->require(2)) {
+			ret = ERROR_HLS_DECODE_ERROR;
+			srs_error("hls decode video avc sequenc header sps size failed. ret=%d", ret);
+			return ret;
+		}
+		sequenceParameterSetLength = stream->read_2bytes();
+		if (!stream->require(sequenceParameterSetLength)) {
+			ret = ERROR_HLS_DECODE_ERROR;
+			srs_error("hls decode video avc sequenc header sps data failed. ret=%d", ret);
+			return ret;
+		}
+		if (sequenceParameterSetLength > 0) {
+			srs_freepa(sequenceParameterSetNALUnit);
+			sequenceParameterSetNALUnit = new char[sequenceParameterSetLength];
+			memcpy(sequenceParameterSetNALUnit, stream->current(), sequenceParameterSetLength);
+			stream->skip(sequenceParameterSetLength);
+		}
+		// 1 pps
+		if (!stream->require(1)) {
+			ret = ERROR_HLS_DECODE_ERROR;
+			srs_error("hls decode video avc sequenc header pps failed. ret=%d", ret);
+			return ret;
+		}
+		int8_t numOfPictureParameterSets = stream->read_1bytes();
+		numOfPictureParameterSets &= 0x1f;
+		if (numOfPictureParameterSets != 1) {
+			ret = ERROR_HLS_DECODE_ERROR;
+			srs_error("hls decode video avc sequenc header pps failed. ret=%d", ret);
+			return ret;
+		}
+		if (!stream->require(2)) {
+			ret = ERROR_HLS_DECODE_ERROR;
+			srs_error("hls decode video avc sequenc header pps size failed. ret=%d", ret);
+			return ret;
+		}
+		pictureParameterSetLength = stream->read_2bytes();
+		if (!stream->require(pictureParameterSetLength)) {
+			ret = ERROR_HLS_DECODE_ERROR;
+			srs_error("hls decode video avc sequenc header pps data failed. ret=%d", ret);
+			return ret;
+		}
+		if (pictureParameterSetLength > 0) {
+			srs_freepa(pictureParameterSetNALUnit);
+			pictureParameterSetNALUnit = new char[pictureParameterSetLength];
+			memcpy(pictureParameterSetNALUnit, stream->current(), pictureParameterSetLength);
+			stream->skip(pictureParameterSetLength);
+		}
 	} else if (avc_packet_type == SrsCodecVideoAVCTypeNALU){
 		// ensure the sequence header demuxed
 		if (avc_extra_size <= 0 || !avc_extra_data) {
diff --git a/trunk/src/core/srs_core_codec.hpp b/trunk/src/core/srs_core_codec.hpp
index 17d1e2d49..18cc32a5a 100644
--- a/trunk/src/core/srs_core_codec.hpp
+++ b/trunk/src/core/srs_core_codec.hpp
@@ -250,6 +250,10 @@ public:
 	int			duration;
 	// lengthSizeMinusOne, H.264-AVC-ISO_IEC_14496-15.pdf, page 16
 	int8_t 		NAL_unit_length;
+	u_int16_t 	sequenceParameterSetLength;
+	char* 		sequenceParameterSetNALUnit;
+	u_int16_t 	pictureParameterSetLength;
+	char* 		pictureParameterSetNALUnit;
 	/**
 	* audio specified
 	*/
diff --git a/trunk/src/core/srs_core_hls.cpp b/trunk/src/core/srs_core_hls.cpp
index e9665e214..97069c705 100644
--- a/trunk/src/core/srs_core_hls.cpp
+++ b/trunk/src/core/srs_core_hls.cpp
@@ -512,8 +512,13 @@ SrsTSMuxer::SrsTSMuxer()
 {
 	fd = -1;
 	
+	// ffmpeg set the start time to the delay time.
+	base_dts = SRS_HLS_DELAY;
+	
 	audio_buffer = new SrsCodecBuffer();
 	video_buffer = new SrsCodecBuffer();
+
+	got_iframe = false;
 }
 
 SrsTSMuxer::~SrsTSMuxer()
@@ -555,7 +560,7 @@ int SrsTSMuxer::write_audio(u_int32_t time, SrsCodec* codec, SrsCodecSample* sam
 {
 	int ret = ERROR_SUCCESS;
 	
-	audio_frame.dts = audio_frame.pts = time * 90;
+	audio_frame.dts = audio_frame.pts = base_dts + time * 90;
 	audio_frame.pid = TS_AUDIO_PID;
 	audio_frame.sid = TS_AUDIO_AAC;
 	
@@ -626,12 +631,19 @@ int SrsTSMuxer::write_video(u_int32_t time, SrsCodec* codec, SrsCodecSample* sam
 {
 	int ret = ERROR_SUCCESS;
 	
-	video_frame.dts = time * 90;
+	video_frame.dts = base_dts + time * 90;
 	video_frame.pts = video_frame.dts + sample->cts * 90;
 	video_frame.pid = TS_VIDEO_PID;
 	video_frame.sid = TS_VIDEO_AVC;
 	video_frame.key = sample->frame_type == SrsCodecVideoAVCFrameKeyFrame;
 	
+	if (video_frame.key) {
+		got_iframe = true;
+	}
+	if (!got_iframe) {
+		return ret;
+	}
+	
 	static u_int8_t aud_nal[] = { 0x00, 0x00, 0x00, 0x01, 0x09, 0xf0 };
 	video_buffer->append(aud_nal, sizeof(aud_nal));
 	
@@ -646,12 +658,33 @@ int SrsTSMuxer::write_video(u_int32_t time, SrsCodec* codec, SrsCodecSample* sam
 			return ret;
 		}
 		
-		if (false && video_frame.key && !sps_pps_sent) {
-			// sample start prefix
-			video_buffer->append(aud_nal, 4);
-			// sps and pps
-			// TODO: do in right way.
-			video_buffer->append(codec->avc_extra_data, codec->avc_extra_size);
+		// 5bits, 7.3.1 NAL unit syntax, 
+		// H.264-AVC-ISO_IEC_14496-10.pdf, page 44.
+		u_int8_t nal_unit_type;
+		nal_unit_type = *buf->bytes;
+		nal_unit_type &= 0x1f;
+		
+		// Table 7-1 – NAL unit type codes, page 61
+		// 1: Coded slice
+		if (nal_unit_type == 1) {
+			sps_pps_sent = false;
+		}
+		// 5: Coded slice of an IDR picture
+		if (nal_unit_type == 5 && !sps_pps_sent) {
+			// ngx_rtmp_hls_append_sps_pps
+			if (codec->sequenceParameterSetLength > 0) {
+				// AnnexB prefix
+				video_buffer->append(aud_nal, 4);
+				// sps
+				video_buffer->append(codec->sequenceParameterSetNALUnit, codec->sequenceParameterSetLength);
+			}
+			if (codec->pictureParameterSetLength > 0) {
+				// AnnexB prefix
+				video_buffer->append(aud_nal, 4);
+				// pps
+				video_buffer->append(codec->pictureParameterSetNALUnit, codec->pictureParameterSetLength);
+			}
+			
 		}
 		
 		// sample start prefix, '00 00 00 01' or '00 00 01'
diff --git a/trunk/src/core/srs_core_hls.hpp b/trunk/src/core/srs_core_hls.hpp
index fa10ed0fe..8f08c42c1 100644
--- a/trunk/src/core/srs_core_hls.hpp
+++ b/trunk/src/core/srs_core_hls.hpp
@@ -81,6 +81,8 @@ private:
 	int fd;
 	std::string path;
 private:
+	bool got_iframe;
+	int64_t base_dts;
 	mpegts_frame audio_frame;
 	SrsCodecBuffer* audio_buffer;
 	mpegts_frame video_frame;