support pause for live stream.

@@ -48,6 +48,7 @@ url: rtmp://127.0.0.1:1935/live/livestream
 * nginx v1.5.0: 139524 lines <br/>
 * nginx v1.5.0: 139524 lines <br/>
 
 
 ### History
 ### History
+* v0.4, 2013-11-09, support pause for live stream.
 * v0.3, 2013-11-04, v0.3 released. 11773 lines.
 * v0.3, 2013-11-04, v0.3 released. 11773 lines.
 * v0.3, 2013-11-04, support refer/play-refer/publish-refer.
 * v0.3, 2013-11-04, support refer/play-refer/publish-refer.
 * v0.3, 2013-11-04, support vhosts specified config.
 * v0.3, 2013-11-04, support vhosts specified config.

@@ -63,7 +63,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 	(void)0
 	(void)0
 
 
 // current release version
 // current release version
-#define RTMP_SIG_SRS_VERSION "0.2.0"
+#define RTMP_SIG_SRS_VERSION "0.3.0"
 // server info.
 // server info.
 #define RTMP_SIG_SRS_KEY "srs"
 #define RTMP_SIG_SRS_KEY "srs"
 #define RTMP_SIG_SRS_ROLE "origin server"
 #define RTMP_SIG_SRS_ROLE "origin server"

@@ -270,10 +270,9 @@ int SrsClient::playing(SrsSource* source)
 				srs_error("recv client control message failed. ret=%d", ret);
 				srs_error("recv client control message failed. ret=%d", ret);
 				return ret;
 				return ret;
 			}
 			}
-			if (ret == ERROR_SUCCESS && !msg) {
-				srs_info("play loop got a message.");
-				SrsAutoFree(SrsCommonMessage, msg, false);
-				// TODO: process it.
+			if ((ret = process_play_control_msg(consumer, msg)) != ERROR_SUCCESS) {
+				srs_error("process play control message failed. ret=%d", ret);
+				return ret;
 			}
 			}
 		}
 		}
 		
 		
@@ -442,3 +441,44 @@ int SrsClient::get_peer_ip()
     return ret;
     return ret;
 }
 }
 
 
+int SrsClient::process_play_control_msg(SrsConsumer* consumer, SrsCommonMessage* msg)
+{
+	int ret = ERROR_SUCCESS;
+	
+	if (!msg) {
+		srs_verbose("ignore all empty message.");
+		return ret;
+	}
+	SrsAutoFree(SrsCommonMessage, msg, false);
+	
+	if (!msg->header.is_amf0_command() && !msg->header.is_amf3_command()) {
+		srs_info("ignore all message except amf0/amf3 command.");
+		return ret;
+	}
+	
+	if ((ret = msg->decode_packet()) != ERROR_SUCCESS) {
+		srs_error("decode the amf0/amf3 command packet failed. ret=%d", ret);
+		return ret;
+	}
+	srs_info("decode the amf0/amf3 command packet success.");
+	
+	SrsPausePacket* pause = dynamic_cast<SrsPausePacket*>(msg->get_packet());
+	if (!pause) {
+		srs_info("ignore all amf0/amf3 command except pause.");
+		return ret;
+	}
+	
+	if ((ret = rtmp->on_play_client_pause(res->stream_id, pause->is_pause)) != ERROR_SUCCESS) {
+		srs_error("rtmp process play client pause failed. ret=%d", ret);
+		return ret;
+	}
+	
+	if ((ret = consumer->on_play_client_pause(pause->is_pause)) != ERROR_SUCCESS) {
+		srs_error("consumer process play client pause failed. ret=%d", ret);
+		return ret;
+	}
+	srs_info("process pause success, is_pause=%d, time=%d.", pause->is_pause, pause->time_ms);
+	
+    return ret;
+}
+

@@ -37,6 +37,8 @@ class SrsRequest;
 class SrsResponse;
 class SrsResponse;
 class SrsSource;
 class SrsSource;
 class SrsRefer;
 class SrsRefer;
+class SrsConsumer;
+class SrsCommonMessage;
 
 
 /**
 /**
 * the client provides the main logic control for RTMP clients.
 * the client provides the main logic control for RTMP clients.
@@ -59,6 +61,7 @@ private:
 	virtual int playing(SrsSource* source);
 	virtual int playing(SrsSource* source);
 	virtual int publish(SrsSource* source, bool is_fmle);
 	virtual int publish(SrsSource* source, bool is_fmle);
 	virtual int get_peer_ip();
 	virtual int get_peer_ip();
+	virtual int process_play_control_msg(SrsConsumer* consumer, SrsCommonMessage* msg);
 };
 };
 
 
 #endif
 #endif

@@ -195,6 +195,7 @@ messages.
 #define RTMP_AMF0_COMMAND_CONNECT			"connect"
 #define RTMP_AMF0_COMMAND_CONNECT			"connect"
 #define RTMP_AMF0_COMMAND_CREATE_STREAM		"createStream"
 #define RTMP_AMF0_COMMAND_CREATE_STREAM		"createStream"
 #define RTMP_AMF0_COMMAND_PLAY				"play"
 #define RTMP_AMF0_COMMAND_PLAY				"play"
+#define RTMP_AMF0_COMMAND_PAUSE				"pause"
 #define RTMP_AMF0_COMMAND_ON_BW_DONE		"onBWDone"
 #define RTMP_AMF0_COMMAND_ON_BW_DONE		"onBWDone"
 #define RTMP_AMF0_COMMAND_ON_STATUS			"onStatus"
 #define RTMP_AMF0_COMMAND_ON_STATUS			"onStatus"
 #define RTMP_AMF0_COMMAND_RESULT			"_result"
 #define RTMP_AMF0_COMMAND_RESULT			"_result"
@@ -1219,6 +1220,10 @@ int SrsCommonMessage::decode_packet()
 			srs_info("decode the AMF0/AMF3 command(paly message).");
 			srs_info("decode the AMF0/AMF3 command(paly message).");
 			packet = new SrsPlayPacket();
 			packet = new SrsPlayPacket();
 			return packet->decode(stream);
 			return packet->decode(stream);
+		} else if(command == RTMP_AMF0_COMMAND_PAUSE) {
+			srs_info("decode the AMF0/AMF3 command(pause message).");
+			packet = new SrsPausePacket();
+			return packet->decode(stream);
 		} else if(command == RTMP_AMF0_COMMAND_RELEASE_STREAM) {
 		} else if(command == RTMP_AMF0_COMMAND_RELEASE_STREAM) {
 			srs_info("decode the AMF0/AMF3 command(FMLE releaseStream message).");
 			srs_info("decode the AMF0/AMF3 command(FMLE releaseStream message).");
 			packet = new SrsFMLEStartPacket();
 			packet = new SrsFMLEStartPacket();
@@ -1896,6 +1901,61 @@ int SrsPublishPacket::decode(SrsStream* stream)
 	return ret;
 	return ret;
 }
 }
 
 
+SrsPausePacket::SrsPausePacket()
+{
+	command_name = RTMP_AMF0_COMMAND_PAUSE;
+	transaction_id = 0;
+	command_object = new SrsAmf0Null();
+
+	time_ms = 0;
+	is_pause = true;
+}
+
+SrsPausePacket::~SrsPausePacket()
+{
+	srs_freep(command_object);
+}
+
+int SrsPausePacket::decode(SrsStream* stream)
+{
+	int ret = ERROR_SUCCESS;
+
+	if ((ret = srs_amf0_read_string(stream, command_name)) != ERROR_SUCCESS) {
+		srs_error("amf0 decode pause command_name failed. ret=%d", ret);
+		return ret;
+	}
+	if (command_name.empty() || command_name != RTMP_AMF0_COMMAND_PAUSE) {
+		ret = ERROR_RTMP_AMF0_DECODE;
+		srs_error("amf0 decode pause command_name failed. "
+			"command_name=%s, ret=%d", command_name.c_str(), ret);
+		return ret;
+	}
+	
+	if ((ret = srs_amf0_read_number(stream, transaction_id)) != ERROR_SUCCESS) {
+		srs_error("amf0 decode pause transaction_id failed. ret=%d", ret);
+		return ret;
+	}
+	
+	if ((ret = srs_amf0_read_null(stream)) != ERROR_SUCCESS) {
+		srs_error("amf0 decode pause command_object failed. ret=%d", ret);
+		return ret;
+	}
+	
+	if ((ret = srs_amf0_read_boolean(stream, is_pause)) != ERROR_SUCCESS) {
+		srs_error("amf0 decode pause is_pause failed. ret=%d", ret);
+		return ret;
+	}
+	
+	if ((ret = srs_amf0_read_number(stream, time_ms)) != ERROR_SUCCESS) {
+		srs_error("amf0 decode pause time_ms failed. ret=%d", ret);
+		return ret;
+	}
+	
+	srs_info("amf0 decode pause packet success");
+	
+	return ret;
+}
+
 SrsPlayPacket::SrsPlayPacket()
 SrsPlayPacket::SrsPlayPacket()
 {
 {
 	command_name = RTMP_AMF0_COMMAND_PLAY;
 	command_name = RTMP_AMF0_COMMAND_PLAY;

@@ -637,6 +637,33 @@ public:
 };
 };
 
 
 /**
 /**
+* 4.2.8. pause
+* The client sends the pause command to tell the server to pause or
+* start playing.
+*/
+class SrsPausePacket : public SrsPacket
+{
+private:
+	typedef SrsPacket super;
+protected:
+	virtual const char* get_class_name()
+	{
+		return CLASS_NAME_STRING(SrsPausePacket);
+	}
+public:
+	std::string command_name;
+	double transaction_id;
+	SrsAmf0Null* command_object;
+	bool is_pause;
+	double time_ms;
+public:
+	SrsPausePacket();
+	virtual ~SrsPausePacket();
+public:
+	virtual int decode(SrsStream* stream);
+};
+
+/**
 * 4.2.1. play
 * 4.2.1. play
 * The client sends this command to the server to play a stream.
 * The client sends this command to the server to play a stream.
 */
 */
@@ -960,12 +987,12 @@ protected:
 enum SrcPCUCEventType
 enum SrcPCUCEventType
 {
 {
 	 // generally, 4bytes event-data
 	 // generally, 4bytes event-data
-	SrcPCUCStreamBegin 		= 0x00,
+	SrcPCUCStreamBegin 			= 0x00,
 	SrcPCUCStreamEOF 			= 0x01,
 	SrcPCUCStreamEOF 			= 0x01,
 	SrcPCUCStreamDry 			= 0x02,
 	SrcPCUCStreamDry 			= 0x02,
-	SrcPCUCSetBufferLength 	= 0x03, // 8bytes event-data
+	SrcPCUCSetBufferLength 		= 0x03, // 8bytes event-data
 	SrcPCUCStreamIsRecorded 	= 0x04,
 	SrcPCUCStreamIsRecorded 	= 0x04,
-	SrcPCUCPingRequest 		= 0x06,
+	SrcPCUCPingRequest 			= 0x06,
 	SrcPCUCPingResponse 		= 0x07,
 	SrcPCUCPingResponse 		= 0x07,
 };
 };
 
 

@@ -34,34 +34,36 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 /**
 /**
 * the signature for packets to client.
 * the signature for packets to client.
 */
 */
-#define RTMP_SIG_FMS_VER "3,5,3,888"
-#define RTMP_SIG_AMF0_VER 0
-#define RTMP_SIG_CLIENT_ID "ASAICiss"
+#define RTMP_SIG_FMS_VER 					"3,5,3,888"
+#define RTMP_SIG_AMF0_VER 					0
+#define RTMP_SIG_CLIENT_ID 					"ASAICiss"
 
 
 /**
 /**
 * onStatus consts.
 * onStatus consts.
 */
 */
-#define StatusLevel "level"
-#define StatusCode "code"
-#define StatusDescription "description"
-#define StatusDetails "details"
-#define StatusClientId "clientid"
+#define StatusLevel 						"level"
+#define StatusCode 							"code"
+#define StatusDescription 					"description"
+#define StatusDetails 						"details"
+#define StatusClientId 						"clientid"
 // status value
 // status value
-#define StatusLevelStatus "status"
+#define StatusLevelStatus 					"status"
 // code value
 // code value
-#define StatusCodeConnectSuccess "NetConnection.Connect.Success"
-#define StatusCodeStreamReset "NetStream.Play.Reset"
-#define StatusCodeStreamStart "NetStream.Play.Start"
-#define StatusCodePublishStart "NetStream.Publish.Start"
-#define StatusCodeDataStart "NetStream.Data.Start"
-#define StatusCodeUnpublishSuccess "NetStream.Unpublish.Success"
+#define StatusCodeConnectSuccess 			"NetConnection.Connect.Success"
+#define StatusCodeStreamReset 				"NetStream.Play.Reset"
+#define StatusCodeStreamStart 				"NetStream.Play.Start"
+#define StatusCodeStreamPause 				"NetStream.Pause.Notify"
+#define StatusCodeStreamUnpause 			"NetStream.Unpause.Notify"
+#define StatusCodePublishStart 				"NetStream.Publish.Start"
+#define StatusCodeDataStart 				"NetStream.Data.Start"
+#define StatusCodeUnpublishSuccess 			"NetStream.Unpublish.Success"
 
 
 // FMLE
 // FMLE
 #define RTMP_AMF0_COMMAND_ON_FC_PUBLISH		"onFCPublish"
 #define RTMP_AMF0_COMMAND_ON_FC_PUBLISH		"onFCPublish"
 #define RTMP_AMF0_COMMAND_ON_FC_UNPUBLISH	"onFCUnpublish"
 #define RTMP_AMF0_COMMAND_ON_FC_UNPUBLISH	"onFCUnpublish"
 
 
 // default stream id for response the createStream request.
 // default stream id for response the createStream request.
-#define SRS_DEFAULT_SID 1
+#define SRS_DEFAULT_SID 					1
 
 
 SrsRequest::SrsRequest()
 SrsRequest::SrsRequest()
 {
 {
@@ -570,6 +572,81 @@ int SrsRtmp::start_play(int stream_id)
 	return ret;
 	return ret;
 }
 }
 
 
+int SrsRtmp::on_play_client_pause(int stream_id, bool is_pause)
+{
+	int ret = ERROR_SUCCESS;
+	
+	if (is_pause) {
+		// onStatus(NetStream.Pause.Notify)
+		if (true) {
+			SrsCommonMessage* msg = new SrsCommonMessage();
+			SrsOnStatusCallPacket* pkt = new SrsOnStatusCallPacket();
+			
+			pkt->data->set(StatusLevel, new SrsAmf0String(StatusLevelStatus));
+			pkt->data->set(StatusCode, new SrsAmf0String(StatusCodeStreamPause));
+			pkt->data->set(StatusDescription, new SrsAmf0String("Paused stream."));
+			
+			msg->set_packet(pkt, stream_id);
+			
+			if ((ret = protocol->send_message(msg)) != ERROR_SUCCESS) {
+				srs_error("send onStatus(NetStream.Pause.Notify) message failed. ret=%d", ret);
+				return ret;
+			}
+			srs_info("send onStatus(NetStream.Pause.Notify) message success.");
+		}
+		// StreamEOF
+		if (true) {
+			SrsCommonMessage* msg = new SrsCommonMessage();
+			SrsUserControlPacket* pkt = new SrsUserControlPacket();
+			
+			pkt->event_type = SrcPCUCStreamEOF;
+			pkt->event_data = stream_id;
+			msg->set_packet(pkt, 0);
+			
+			if ((ret = protocol->send_message(msg)) != ERROR_SUCCESS) {
+				srs_error("send PCUC(StreamEOF) message failed. ret=%d", ret);
+				return ret;
+			}
+			srs_info("send PCUC(StreamEOF) message success.");
+		}
+	} else {
+		// onStatus(NetStream.Unpause.Notify)
+		if (true) {
+			SrsCommonMessage* msg = new SrsCommonMessage();
+			SrsOnStatusCallPacket* pkt = new SrsOnStatusCallPacket();
+			
+			pkt->data->set(StatusLevel, new SrsAmf0String(StatusLevelStatus));
+			pkt->data->set(StatusCode, new SrsAmf0String(StatusCodeStreamUnpause));
+			pkt->data->set(StatusDescription, new SrsAmf0String("Unpaused stream."));
+			
+			msg->set_packet(pkt, stream_id);
+			
+			if ((ret = protocol->send_message(msg)) != ERROR_SUCCESS) {
+				srs_error("send onStatus(NetStream.Unpause.Notify) message failed. ret=%d", ret);
+				return ret;
+			}
+			srs_info("send onStatus(NetStream.Unpause.Notify) message success.");
+		}
+		// StreanBegin
+		if (true) {
+			SrsCommonMessage* msg = new SrsCommonMessage();
+			SrsUserControlPacket* pkt = new SrsUserControlPacket();
+			
+			pkt->event_type = SrcPCUCStreamBegin;
+			pkt->event_data = stream_id;
+			msg->set_packet(pkt, 0);
+			
+			if ((ret = protocol->send_message(msg)) != ERROR_SUCCESS) {
+				srs_error("send PCUC(StreanBegin) message failed. ret=%d", ret);
+				return ret;
+			}
+			srs_info("send PCUC(StreanBegin) message success.");
+		}
+	}
+	
+	return ret;
+}
+
 int SrsRtmp::start_fmle_publish(int stream_id)
 int SrsRtmp::start_fmle_publish(int stream_id)
 {
 {
 	int ret = ERROR_SUCCESS;
 	int ret = ERROR_SUCCESS;

@@ -148,6 +148,16 @@ public:
 	*/
 	*/
 	virtual int start_play(int stream_id);
 	virtual int start_play(int stream_id);
 	/**
 	/**
+	* when client(type is play) send pause message,
+	* if is_pause, response the following packets:
+	* 	onStatus(NetStream.Pause.Notify)
+	* 	StreamEOF
+	* if not is_pause, response the following packets:
+	* 	onStatus(NetStream.Unpause.Notify)
+	* 	StreamBegin
+	*/
+	virtual int on_play_client_pause(int stream_id, bool is_pause);
+	/**
 	* when client type is publish, response with packets:
 	* when client type is publish, response with packets:
 	* releaseStream response
 	* releaseStream response
 	* FCPublish
 	* FCPublish

@@ -31,8 +31,9 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <srs_core_amf0.hpp>
 #include <srs_core_amf0.hpp>
 #include <srs_core_codec.hpp>
 #include <srs_core_codec.hpp>
 
 
-#define CONST_MAX_JITTER_MS 500
-#define DEFAULT_FRAME_TIME_MS 10
+#define CONST_MAX_JITTER_MS 		500
+#define DEFAULT_FRAME_TIME_MS 		10
+#define PAUSED_SHRINK_SIZE			250
 
 
 std::map<std::string, SrsSource*> SrsSource::pool;
 std::map<std::string, SrsSource*> SrsSource::pool;
 
 
@@ -50,16 +51,14 @@ SrsConsumer::SrsConsumer(SrsSource* _source)
 {
 {
 	source = _source;
 	source = _source;
 	last_pkt_correct_time = last_pkt_time = 0;
 	last_pkt_correct_time = last_pkt_time = 0;
+	paused = false;
+	codec = new SrsCodec();
 }
 }
 
 
 SrsConsumer::~SrsConsumer()
 SrsConsumer::~SrsConsumer()
 {
 {
-	std::vector<SrsSharedPtrMessage*>::iterator it;
-	for (it = msgs.begin(); it != msgs.end(); ++it) {
-		SrsSharedPtrMessage* msg = *it;
-		srs_freep(msg);
-	}
-	msgs.clear();
+	clear();	
+	srs_freep(codec);
 	
 	
 	source->on_consumer_destroy(this);
 	source->on_consumer_destroy(this);
 }
 }
@@ -89,6 +88,13 @@ int SrsConsumer::get_packets(int max_count, SrsSharedPtrMessage**& pmsgs, int& c
 	if (msgs.empty()) {
 	if (msgs.empty()) {
 		return ret;
 		return ret;
 	}
 	}
+
+	if (paused) {
+		if ((int)msgs.size() >= PAUSED_SHRINK_SIZE) {
+			shrink();
+		}
+		return ret;
+	}
 	
 	
 	if (max_count == 0) {
 	if (max_count == 0) {
 		count = (int)msgs.size();
 		count = (int)msgs.size();
@@ -111,6 +117,68 @@ int SrsConsumer::get_packets(int max_count, SrsSharedPtrMessage**& pmsgs, int& c
 	return ret;
 	return ret;
 }
 }
 
 
+int SrsConsumer::on_play_client_pause(bool is_pause)
+{
+	int ret = ERROR_SUCCESS;
+	
+	srs_trace("stream consumer change pause state %d=>%d", paused, is_pause);
+	paused = is_pause;
+	
+	return ret;
+}
+
+void SrsConsumer::shrink()
+{
+	int i = 0;
+	std::vector<SrsSharedPtrMessage*>::iterator it;
+	
+	// issue the last video iframe.
+	bool has_video = false;
+	int frame_to_remove = 0;
+	std::vector<SrsSharedPtrMessage*>::iterator iframe = msgs.end();
+	for (i = 0, it = msgs.begin(); it != msgs.end(); ++it, i++) {
+		SrsSharedPtrMessage* msg = *it;
+		if (msg->header.is_video()) {
+			has_video = true;
+			if (codec->video_is_keyframe(msg->payload, msg->size)) {
+				iframe = it;
+				frame_to_remove = i + 1;
+			}
+		}
+	}
+	
+	// last iframe is the first elem, ignore it.
+	if (iframe == msgs.begin()) {
+		return;
+	}
+	
+	// recalc the frame to remove
+	if (iframe == msgs.end()) {
+		frame_to_remove = 0;
+	}
+	if (!has_video) {
+		frame_to_remove = (int)msgs.size();
+	}
+	
+	srs_trace("shrink the cache queue, has_video=%d, has_iframe=%d, size=%d, removed=%d", 
+		has_video, iframe != msgs.end(), (int)msgs.size(), frame_to_remove);
+	
+	// if no video, remove all audio.
+	if (!has_video) {
+		clear();
+		return;
+	}
+	
+	// if exists video Iframe, remove the frames before it.
+	if (iframe != msgs.end()) {
+		for (it = msgs.begin(); it != iframe; ++it) {
+			SrsSharedPtrMessage* msg = *it;
+			srs_freep(msg);
+		}
+		msgs.erase(msgs.begin(), iframe);
+	}
+}
+
 int SrsConsumer::jitter_correct(SrsSharedPtrMessage* msg, int audio_sample_rate)
 int SrsConsumer::jitter_correct(SrsSharedPtrMessage* msg, int audio_sample_rate)
 {
 {
 	int ret = ERROR_SUCCESS;
 	int ret = ERROR_SUCCESS;
@@ -156,6 +224,16 @@ int SrsConsumer::jitter_correct(SrsSharedPtrMessage* msg, int audio_sample_rate)
 	return ret;
 	return ret;
 }
 }
 
 
+void SrsConsumer::clear()
+{
+	std::vector<SrsSharedPtrMessage*>::iterator it;
+	for (it = msgs.begin(); it != msgs.end(); ++it) {
+		SrsSharedPtrMessage* msg = *it;
+		srs_freep(msg);
+	}
+	msgs.clear();
+}
+
 SrsSource::SrsSource(std::string _stream_url)
 SrsSource::SrsSource(std::string _stream_url)
 {
 {
 	stream_url = _stream_url;
 	stream_url = _stream_url;

@@ -50,6 +50,8 @@ private:
 	int32_t last_pkt_correct_time;
 	int32_t last_pkt_correct_time;
 	SrsSource* source;
 	SrsSource* source;
 	std::vector<SrsSharedPtrMessage*> msgs;
 	std::vector<SrsSharedPtrMessage*> msgs;
+	bool paused;
+	SrsCodec* codec;
 public:
 public:
 	SrsConsumer(SrsSource* _source);
 	SrsConsumer(SrsSource* _source);
 	virtual ~SrsConsumer();
 	virtual ~SrsConsumer();
@@ -69,11 +71,21 @@ public:
 	* @max_count the max count to dequeue, 0 to dequeue all.
 	* @max_count the max count to dequeue, 0 to dequeue all.
 	*/
 	*/
 	virtual int get_packets(int max_count, SrsSharedPtrMessage**& pmsgs, int& count);
 	virtual int get_packets(int max_count, SrsSharedPtrMessage**& pmsgs, int& count);
+	/**
+	* when client send the pause message.
+	*/
+	virtual int on_play_client_pause(bool is_pause);
 private:
 private:
 	/**
 	/**
+	* when paused, shrink the cache queue,
+	* remove to cache only one gop.
+	*/
+	virtual void shrink();
+	/**
 	* detect the time jitter and correct it.
 	* detect the time jitter and correct it.
 	*/
 	*/
 	virtual int jitter_correct(SrsSharedPtrMessage* msg, int audio_sample_rate);
 	virtual int jitter_correct(SrsSharedPtrMessage* msg, int audio_sample_rate);
+	virtual void clear();
 };
 };
 
 
 /**
 /**