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-rw-r--r--src/base/UMusic.pas74
1 files changed, 47 insertions, 27 deletions
diff --git a/src/base/UMusic.pas b/src/base/UMusic.pas
index e349bd1f..03d20740 100644
--- a/src/base/UMusic.pas
+++ b/src/base/UMusic.pas
@@ -250,8 +250,8 @@ type
TAudioPlaybackStream = class(TAudioProcessingStream)
protected
+ AvgSyncDiff: double; //** average difference between stream and sync clock
SyncSource: TSyncSource;
- AvgSyncDiff: double;
SourceStream: TAudioSourceStream;
function GetLatency(): double; virtual; abstract;
@@ -260,7 +260,7 @@ type
procedure SetVolume(Volume: single); virtual; abstract;
function Synchronize(BufferSize: integer; FormatInfo: TAudioFormatInfo): integer;
procedure FillBufferWithFrame(Buffer: PByteArray; BufferSize: integer; Frame: PByteArray; FrameSize: integer);
- public
+ public
(**
* Opens a SourceStream for playback.
* Note that the caller (not the TAudioPlaybackStream) is responsible to
@@ -995,6 +995,8 @@ begin
AvgSyncDiff := -1;
end;
+{.$DEFINE LOG_SYNC}
+
(*
* Results an adjusted size of the input buffer size to keep the stream in sync
* with the SyncSource. If no SyncSource was assigned to this stream, the
@@ -1011,11 +1013,15 @@ end;
function TAudioPlaybackStream.Synchronize(BufferSize: integer; FormatInfo: TAudioFormatInfo): integer;
var
TimeDiff: double;
- TimeCorrectionFactor: double;
+ FrameDiff: double;
+ FrameSkip: integer;
+ ReqFrames: integer;
+ MasterClock: real;
+ CurPosition: real;
const
- AVG_HISTORY_FACTOR = 0.9;
- SYNC_THRESHOLD = 0.045;
- MAX_SYNC_DIFF_TIME = 0.002;
+ AVG_HISTORY_FACTOR = 0.7;
+ SYNC_REPOS_THRESHOLD = 5.000;
+ SYNC_SOFT_THRESHOLD = 0.010;
begin
Result := BufferSize;
@@ -1025,9 +1031,12 @@ begin
if (BufferSize <= 0) then
Exit;
+ CurPosition := Position;
+ MasterClock := SyncSource.GetClock();
+
// difference between sync-source and stream position
// (negative if the music-stream's position is ahead of the master clock)
- TimeDiff := SyncSource.GetClock() - (Position - GetLatency());
+ TimeDiff := MasterClock - CurPosition;
// calculate average time difference (some sort of weighted mean).
// The bigger AVG_HISTORY_FACTOR is, the smoother is the average diff.
@@ -1042,35 +1051,46 @@ begin
AvgSyncDiff := TimeDiff * (1-AVG_HISTORY_FACTOR) +
AvgSyncDiff * AVG_HISTORY_FACTOR;
- // check if sync needed
- if (Abs(AvgSyncDiff) >= SYNC_THRESHOLD) then
+ {$IFDEF LOG_SYNC}
+ //Log.LogError(Format('c:%.3f | p:%.3f | d:%.3f | a:%.3f',
+ // [MasterClock, CurPosition, TimeDiff, AvgSyncDiff]), 'Synch');
+ {$ENDIF}
+
+ // check if we are out of sync
+ if (Abs(AvgSyncDiff) >= SYNC_REPOS_THRESHOLD) then
begin
- // TODO: use SetPosition if diff is too large (>5s)
- if (TimeDiff < 1) then
- TimeCorrectionFactor := Sign(TimeDiff)*TimeDiff*TimeDiff
- else
- TimeCorrectionFactor := TimeDiff;
-
- // calculate adapted buffer size
- // reduce size of data to fetch if music is ahead, increase otherwise
- Result := BufferSize + Round(TimeCorrectionFactor * FormatInfo.SampleRate) * FormatInfo.FrameSize;
+ {$IFDEF LOG_SYNC}
+ Log.LogError(Format('ReposSynch: %.3f > %.3f',
+ [Abs(AvgSyncDiff), SYNC_REPOS_THRESHOLD]), 'Synch');
+ {$ENDIF}
+
+ // diff far is too large -> reposition stream
+ // (resulting position might still be out of sync)
+ SetPosition(CurPosition + AvgSyncDiff);
+
+ // reset sync info
+ AvgSyncDiff := -1;
+ end
+ else if (Abs(AvgSyncDiff) >= SYNC_SOFT_THRESHOLD) then
+ begin
+ {$IFDEF LOG_SYNC}
+ Log.LogError(Format('SoftSynch: %.3f > %.3f',
+ [Abs(AvgSyncDiff), SYNC_SOFT_THRESHOLD]), 'Synch');
+ {$ENDIF}
+
+ // hard sync: directly jump to the current position
+ FrameSkip := Round(AvgSyncDiff * FormatInfo.SampleRate);
+ Result := BufferSize + FrameSkip * FormatInfo.FrameSize;
if (Result < 0) then
Result := 0;
- // reset average
+ // reset sync info
AvgSyncDiff := -1;
end;
-
- (*
- DebugWriteln('Diff: ' + floattostrf(TimeDiff, ffFixed, 15, 3) +
- '| SyS: ' + floattostrf(SyncSource.GetClock(), ffFixed, 15, 3) +
- '| Pos: ' + floattostrf(Position, ffFixed, 15, 3) +
- '| Avg: ' + floattostrf(AvgSyncDiff, ffFixed, 15, 3));
- *)
end;
(*
- * Fills a buffer with copies of the given frame or with 0 if frame.
+ * Fills a buffer with copies of the given Frame or with 0 if Frame is nil.
*)
procedure TAudioPlaybackStream.FillBufferWithFrame(Buffer: PByteArray; BufferSize: integer; Frame: PByteArray; FrameSize: integer);
var