VPLAY-12359 suboptimal UTCTiming behavior

AampConfig.cpp

@@ -368,7 +368,8 @@ static const ConfigLookupEntryBool mConfigLookupTableBool[AAMPCONFIG_BOOL_COUNT]
 	{false, "curlThroughput", eAAMPConfig_CurlThroughput, false },
 	{false, "useFireboltSDK", eAAMPConfig_UseFireboltSDK, false},
 	{true, "enableChunkInjection", eAAMPConfig_EnableChunkInjection, true},
-	{false, "debugChunkTransfer", eAAMPConfig_DebugChunkTransfer, false}
+	{false, "debugChunkTransfer", eAAMPConfig_DebugChunkTransfer, false},
+	{true, "utcSyncOnStartup", eAAMPConfig_UTCSyncOnStartup, true}
 };
 
 #define CONFIG_INT_ALIAS_COUNT 2
@@ -468,9 +469,13 @@ static const ConfigLookupEntryInt mConfigLookupTableInt[AAMPCONFIG_INT_COUNT+CON
 	{DEFAULT_MONITOR_AV_JUMP_THRESHOLD_MS,"monitorAVJumpThreshold",eAAMPConfig_MonitorAVJumpThreshold,true,eCONFIG_RANGE_MONITOR_AVSYNC_JUMP_THRESHOLD },
 	{DEFAULT_PROGRESS_LOGGING_DIVISOR,"progressLoggingDivisor",eAAMPConfig_ProgressLoggingDivisor,false},
 	{DEFAULT_MONITOR_AV_REPORTING_INTERVAL, "monitorAVReportingInterval", eAAMPConfig_MonitorAVReportingInterval, false},
-	// aliases, kept for backwards compatibility
+	{DEFAULT_UTC_SYNC_MIN_INTERVAL,"utcSyncMinIntervalSec",eAAMPConfig_UTCSyncMinIntervalSec,true },
+
+	// Add new integer config entries above this line, before the aliases section.
+	//
+	// Aliases, kept for backwards compatibility
 	{DEFAULT_INIT_BITRATE,"defaultBitrate",eAAMPConfig_DefaultBitrate,true },
-	{DEFAULT_INIT_BITRATE_4K,"defaultBitrate4K",eAAMPConfig_DefaultBitrate4K,true },
+	{DEFAULT_INIT_BITRATE_4K,"defaultBitrate4K",eAAMPConfig_DefaultBitrate4K,true }
 };
 
 /**
@@ -495,7 +500,7 @@ static const ConfigLookupEntryFloat mConfigLookupTableFloat[AAMPCONFIG_FLOAT_COU
 	{DEFAULT_NORMAL_RATE_CORRECTION_SPEED,"normalLatencyCorrectionPlaybackRate",eAAMPConfig_NormalLatencyCorrectionPlaybackRate,false},
 	{DEFAULT_MIN_BUFFER_LOW_LATENCY,"lowLatencyMinBuffer",eAAMPConfig_LowLatencyMinBuffer,true, eCONFIG_RANGE_LLDBUFFER},
 	{DEFAULT_TARGET_BUFFER_LOW_LATENCY,"lowLatencyTargetBuffer",eAAMPConfig_LowLatencyTargetBuffer,true, eCONFIG_RANGE_LLDBUFFER},
-	{GST_BW_TO_BUFFER_FACTOR,"bandwidthToBufferFactor", eAAMPConfig_BWToGstBufferFactor,true},
+	{GST_BW_TO_BUFFER_FACTOR,"bandwidthToBufferFactor", eAAMPConfig_BWToGstBufferFactor,true}
 };
 
 /**

AampConfig.h

@@ -214,6 +214,7 @@ typedef enum
 	eAAMPConfig_UseFireboltSDK,						/**< Config to use Firebolt SDK for license Acquisition */
 	eAAMPConfig_EnableChunkInjection,					/**< Config to enable chunk injection for low latency DASH */
 	eAAMPConfig_DebugChunkTransfer,					/**< app-managed chunked transfer protocol */
+	eAAMPConfig_UTCSyncOnStartup,					/**< Perform sync at startup */
 	eAAMPConfig_BoolMaxValue						/**< Max value of bool config always last element */
 
 } AAMPConfigSettingBool;
@@ -311,6 +312,7 @@ typedef enum
 	eAAMPConfig_MonitorAVJumpThreshold,				/**< configures threshold aligned audio,video positions advancing together by unexpectedly large delta to be reported as jump in milliseconds*/
 	eAAMPConfig_ProgressLoggingDivisor,				/**<  Divisor to avoid printing the progress report too frequently in the log */
 	eAAMPConfig_MonitorAVReportingInterval,			/**< Timeout in milliseconds for reporting MonitorAV events */
+	eAAMPConfig_UTCSyncMinIntervalSec,				/**< Minimum interval between sync attempts */
 	eAAMPConfig_IntMaxValue							/**< Max value of int config always last element*/
 } AAMPConfigSettingInt;
 #define AAMPCONFIG_INT_COUNT (eAAMPConfig_IntMaxValue)

AampDefine.h

@@ -143,6 +143,8 @@
 #define DEFAULT_MONITOR_AV_JUMP_THRESHOLD_MS 100 	/**< default jump threshold to MonitorAV reporting */
 #define DEFAULT_MAX_DOWNLOAD_BUFFER 10	/**< Default maximum download buffer in seconds, this can be used to limit player download job scheduling for DASH */
 #define DEFAULT_MONITOR_AV_REPORTING_INTERVAL 1000 /**< time interval in ms for MonitorAV reporting */
+#define DEFAULT_UTC_SYNC_MIN_INTERVAL	60	/**< Minimum interval between sync attempts */
+
 
 // We can enable the following once we have a thread monitoring video PTS progress and triggering subtec clock fast update when we detect video freeze. Disabled it for now for brute force fast refresh..
 //#define SUBTEC_VARIABLE_CLOCK_UPDATE_RATE   /* enable this to make the clock update rate dynamic*/

fragmentcollector_mpd.cpp

@@ -4468,11 +4468,13 @@ void StreamAbstractionAAMP_MPD::FindPeriodGapsAndReport()
 	}
 }
 
+TimeSyncClient::TimeSyncClient(): lastSync(aamp_GetCurrentTimeMS()), lastOffset(0), hasSynced(false) {}
+
 /**
  * @brief Read UTCTiming _element_
  * @retval Return true if UTCTiming _element_ is available in the manifest
  */
-bool  StreamAbstractionAAMP_MPD::FindServerUTCTime(Node* root)
+bool StreamAbstractionAAMP_MPD::FindServerUTCTime(Node* root)
 {
 	bool hasServerUtcTime = false;
 	if( root )
@@ -4505,16 +4507,40 @@ bool  StreamAbstractionAAMP_MPD::FindServerUTCTime(Node* root)
 							aamp_ResolveURL(ServerUrl, aamp->GetManifestUrl(), valueCopy.c_str(), false);
 						}
 
-						mLocalUtcTime = GetNetworkTime(ServerUrl, &http_error, aamp->GetNetworkProxy());
-						if(mLocalUtcTime > 0 )
+						bool shouldSyncOnStartup = !mTimeSyncClient.hasSynced && ISCONFIGSET(eAAMPConfig_UTCSyncOnStartup);
+						bool intervalElapsed = false;
+						if( !shouldSyncOnStartup )
 						{
-							double currentTime = (double)aamp_GetCurrentTimeMS() / 1000;
-							mDeltaTime =  mLocalUtcTime - currentTime;
-							hasServerUtcTime = true;
+							const double elapsed = (double)(aamp_GetCurrentTimeMS() - mTimeSyncClient.lastSync) / 1000;
+							intervalElapsed = elapsed >= GETCONFIGVALUE(eAAMPConfig_UTCSyncMinIntervalSec);
 						}
-						else
+						if (shouldSyncOnStartup || intervalElapsed)
+						{
+							mLocalUtcTime = GetNetworkTime(ServerUrl, &http_error, aamp->GetNetworkProxy());
+							if(mLocalUtcTime > 0)
+							{
+								mTimeSyncClient.lastSync = aamp_GetCurrentTimeMS();
+								mDeltaTime =  mLocalUtcTime - (double)mTimeSyncClient.lastSync / 1000;
+								mTimeSyncClient.lastOffset = mDeltaTime;
+								mTimeSyncClient.hasSynced = true;
+								hasServerUtcTime = true;
+							}
+							else
+							{
+								if (!mTimeSyncClient.hasSynced)
+								{
+									AAMPLOG_ERR("Failed initial read of timeServer [%s] RetCode[%d]", ServerUrl.c_str(), http_error);
+								}
+								else
+								{
+									AAMPLOG_WARN("Failed to refresh timeServer [%s] RetCode[%d]", ServerUrl.c_str(), http_error);
+								}
+							}
+						}
+						else if(mTimeSyncClient.hasSynced)
 						{
-							AAMPLOG_ERR("Failed to read timeServer [%s] RetCode[%d]",ServerUrl.c_str(),http_error);
+							mDeltaTime = mTimeSyncClient.lastOffset;
+							hasServerUtcTime = true;
 						}
 						break;
 					}

fragmentcollector_mpd.h

@@ -67,6 +67,45 @@ struct ProfileInfo
 	int representationIndex;
 };
 
+/**
+ * @struct TimeSyncClient
+ *
+ * @brief Maintains state for periodic synchronization of the local clock
+ * with a remote UTC time server, used in DASH manifest processing.
+ *
+ * This struct tracks the last successful synchronization time and the
+ * cached offset between the local system clock and the server's UTC time.
+ * It supports logic to determine when a new synchronization request should
+ * be made based on elapsed time and configuration.
+ *
+ * Members:
+ * - lastSync: Timestamp (milliseconds since epoch) of the last successful sync.
+ * - lastOffset: Cached time delta (in seconds) between local and server time.
+ * - hasSynced: Flag indicating whether at least one successful sync has occurred.
+ */
+struct TimeSyncClient
+{
+	/**
+	 * @brief UTC time in milliseconds since epoch when time was last synchronized with time server.
+	 */
+	long long lastSync;
+
+	/**
+	 * @brief Current delta (seconds) between local and server time.
+	 */
+	double lastOffset;
+
+	/**
+	 * @brief True if time has been synchronized at least once.
+	 */
+	bool hasSynced;
+
+	/**
+	 * @brief Constructor initializes lastSync with current time and resets other members.
+	 */
+	TimeSyncClient();
+};
+
 class AampDashWorkerJob : public aamp::AampTrackWorkerJob
 {
 private:
@@ -1244,6 +1283,7 @@ class StreamAbstractionAAMP_MPD : public StreamAbstractionAAMP
 	bool mShortAdOffsetCalc;
 	AampTime mNextPts;					/*For PTS restamping*/
 	bool mIsFinalFirstPTS; /**< Flag to indicate if the first PTS is final or not */
+	TimeSyncClient mTimeSyncClient;
 };
 
 #endif //FRAGMENTCOLLECTOR_MPD_H_