Make AEAudioFilePlayerModule take AudioTimeStamp values for playback …

…scheduling This allows scheduling to function in offline mode. Use the new AETimeStamp functions to convert host ticks or samples to AudioTimeStamps.
cjhanson · Jul 2, 2016 · afff5e7 · afff5e7
1 parent 310aeb6
commit afff5e7
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Showing 6 changed files with 72 additions and 31 deletions.
diff --git a/TAAESample/Classes/AEAudioController.m b/TAAESample/Classes/AEAudioController.m
@@ -328,7 +328,7 @@ - (void)playRecordingWithCompletionBlock:(void (^)())block {
 
         // Go
         self.playingRecording = YES;
-        [player playAtTime:0];
+        [player playAtTime:AETimeStampNone];
     }
 }
 

diff --git a/TAAESample/Classes/ViewController.swift b/TAAESample/Classes/ViewController.swift
@@ -127,7 +127,7 @@ class ViewController: UIViewController {
 
                     // Start player
                     player.currentTime = 0
-                    player.playAtTime(syncTime, beginBlock: {
+                    player.playAtTime(AETimeStampWithHostTicks(syncTime), beginBlock: {
                         // Show playing state
                         sender.rotateSpeed = self.currentRotateSpeed()
                     })
@@ -159,7 +159,7 @@ class ViewController: UIViewController {
 
                     // Start player
                     player.currentTime = 0
-                    player.playAtTime(syncTime, beginBlock: {
+                    player.playAtTime(AETimeStampWithHostTicks(syncTime), beginBlock: {
                         // Set button state to playing
                         sender.imageView!.layer.removeAllAnimations()
                         sender.selected = true
@@ -311,7 +311,7 @@ class ViewController: UIViewController {
                 audio.hit.loop = true
                 if !audio.hit.playing {
                     audio.hit.currentTime = 0
-                    audio.hit.playAtTime(audio.nextSyncTimeForPlayer(audio.hit))
+                    audio.hit.playAtTime(AETimeStampWithHostTicks(audio.nextSyncTimeForPlayer(audio.hit)))
                 }
                 hitButton.selected = true
 
@@ -331,7 +331,7 @@ class ViewController: UIViewController {
                 // Start the drums playing again
                 if !audio.drums.playing {
                     audio.drums.currentTime = 0
-                    audio.drums.playAtTime(audio.nextSyncTimeForPlayer(audio.drums))
+                    audio.drums.playAtTime(AETimeStampWithHostTicks(audio.nextSyncTimeForPlayer(audio.drums)))
                     beatButton.rotateSpeed = currentRotateSpeed()
                 }
 

diff --git a/TheAmazingAudioEngine/Core Types/AETime.h b/TheAmazingAudioEngine/Core Types/AETime.h
@@ -29,10 +29,13 @@ extern "C" {
 #endif
 
 #import <Foundation/Foundation.h>
+#import <AudioToolbox/AudioToolbox.h>
 
 typedef uint64_t AEHostTicks;
 typedef double AESeconds;
 
+extern const AudioTimeStamp AETimeStampNone; //!< An empty timestamp
+
 /*!
  * Initialize
  */
@@ -63,6 +66,24 @@ AEHostTicks AEHostTicksFromSeconds(AESeconds seconds);
  * @return The time in seconds
  */
 AESeconds AESecondsFromHostTicks(AEHostTicks ticks);
+
+/*!
+ * Create an AudioTimeStamps with a host ticks value
+ *
+ *  If a zero value is provided, then AETimeStampNone will be returned.
+ *
+ * @param ticks The time in host ticks
+ * @return The timestamp
+ */
+AudioTimeStamp AETimeStampWithHostTicks(AEHostTicks ticks);
+
+/*!
+ * Create an AudioTimeStamps with a sample time value
+ *
+ * @param samples The time in samples
+ * @return The timestamp
+ */
+AudioTimeStamp AETimeStampWithSamples(Float64 samples);
 
 #ifdef __cplusplus
 }

diff --git a/TheAmazingAudioEngine/Core Types/AETime.m b/TheAmazingAudioEngine/Core Types/AETime.m
@@ -30,6 +30,8 @@
 static double __hostTicksToSeconds = 0.0;
 static double __secondsToHostTicks = 0.0;
 
+const AudioTimeStamp AETimeStampNone = {};
+
 void AETimeInit() {
     static dispatch_once_t onceToken;
     dispatch_once(&onceToken, ^{
@@ -60,3 +62,11 @@ AESeconds AESecondsFromHostTicks(AEHostTicks ticks) {
     return ticks * __hostTicksToSeconds;
 }
 
+AudioTimeStamp AETimeStampWithHostTicks(AEHostTicks ticks) {
+    if ( !ticks ) return AETimeStampNone;
+    return (AudioTimeStamp) { .mFlags = kAudioTimeStampHostTimeValid, .mHostTime = ticks };
+}
+
+AudioTimeStamp AETimeStampWithSamples(Float64 samples) {
+    return (AudioTimeStamp) { .mFlags = kAudioTimeStampSampleTimeValid, .mSampleTime = samples };
+}
diff --git a/TheAmazingAudioEngine/Modules/Generation/AEAudioFilePlayerModule.h b/TheAmazingAudioEngine/Modules/Generation/AEAudioFilePlayerModule.h
@@ -67,23 +67,23 @@ typedef void (^AEAudioFilePlayerModuleBlock)();
  *  is reached. Use this method to synchronize playback with other audio
  *  generators.
  *
- *  If you pass 0 as the time, the module will immediately begin outputting
- *  audio.
+ *  If you pass AETimeStampNone as the time, the module will immediately 
+ *  begin outputting audio.
  *
- * @param time The time, in host ticks, at which to begin playback
+ * @param time The timestamp at which to begin playback
  */
-- (void)playAtTime:(AEHostTicks)time;
+- (void)playAtTime:(AudioTimeStamp)time;
 
 /*!
  * Begin playback
  *
  *  Begins playback at the given time; this version allows you to provide a 
  *  block which will be called on the main thread shortly after playback starts.
  *
- * @param time The time, in host ticks, at which to begin playback
+ * @param time The timestamp at which to begin playback
  * @param block Block to call on main thread when the time is reached and playback starts
  */
-- (void)playAtTime:(AEHostTicks)time beginBlock:(AEAudioFilePlayerModuleBlock _Nullable)block;
+- (void)playAtTime:(AudioTimeStamp)time beginBlock:(AEAudioFilePlayerModuleBlock _Nullable)block;
 
 /*!
  * Stop playback

diff --git a/TheAmazingAudioEngine/Modules/Generation/AEAudioFilePlayerModule.m b/TheAmazingAudioEngine/Modules/Generation/AEAudioFilePlayerModule.m
@@ -47,7 +47,7 @@ @interface AEAudioFilePlayerModule () {
     AESeconds   _regionStartTime;
     BOOL        _stopEventScheduled;
     BOOL        _sequenceScheduled;
-    AEHostTicks _startTime;
+    AudioTimeStamp _startTime;
     AEHostTicks _anchorTime;
     double      _playhead;
     UInt32      _remainingMicrofadeInFrames;
@@ -97,18 +97,18 @@ - (void)setCompletionBlock:(void (^)())completionBlock {
     }
 }
 
-- (void)playAtTime:(AEHostTicks)time {
+- (void)playAtTime:(AudioTimeStamp)time {
     [self playAtTime:time beginBlock:nil];
 }
 
-- (void)playAtTime:(AEHostTicks)time beginBlock:(AEAudioFilePlayerModuleBlock)block {
+- (void)playAtTime:(AudioTimeStamp)time beginBlock:(AEAudioFilePlayerModuleBlock)block {
 #ifdef DEBUG
-    if ( time ) {
+    if ( time.mFlags & kAudioTimeStampHostTimeValid ) {
         AEHostTicks now = AECurrentTimeInHostTicks();
-        if ( time < now-AEHostTicksFromSeconds(0.5) ) {
-            NSLog(@"%@: Start time is %lf seconds in the past", self, AESecondsFromHostTicks(now-time));
-        } else if ( time > now+AEHostTicksFromSeconds(60*60) ) {
-            NSLog(@"%@: Start time is %lf seconds in the future", self, AESecondsFromHostTicks(time-now));
+        if ( time.mHostTime < now-AEHostTicksFromSeconds(0.5) ) {
+            NSLog(@"%@: Start time is %lf seconds in the past", self, AESecondsFromHostTicks(now-time.mHostTime));
+        } else if ( time.mHostTime > now+AEHostTicksFromSeconds(60*60) ) {
+            NSLog(@"%@: Start time is %lf seconds in the future", self, AESecondsFromHostTicks(time.mHostTime-now));
         }
     }
 #endif
@@ -134,7 +134,7 @@ - (void)playAtTime:(AEHostTicks)time beginBlock:(AEAudioFilePlayerModuleBlock)bl
 
 - (void)stop {
     self.beginBlock = nil;
-    if ( _startTime ) {
+    if ( _startTime.mFlags != 0 ) {
         // Not yet playing - just stop now
         AECheckOSStatus(AudioUnitReset(self.audioUnit, kAudioUnitScope_Global, 0), "AudioUnitReset");
         _sequenceScheduled = NO;
@@ -432,26 +432,32 @@ static void AEAudioFilePlayerModuleProcess(__unsafe_unretained AEAudioFilePlayer
     }
 
     AudioUnit audioUnit = AEAudioUnitModuleGetAudioUnit(THIS);
-    AEHostTicks startTime = THIS->_startTime;
+    AudioTimeStamp startTime = THIS->_startTime;
     double playhead = THIS->_playhead;
 
     // Check start time
     AEHostTicks hostTimeAtBufferEnd
         = context->timestamp->mHostTime + AEHostTicksFromSeconds((double)context->frames / context->sampleRate);
-    if ( startTime && startTime > hostTimeAtBufferEnd ) {
+    UInt32 sampleTimeAtBufferEnd = context->timestamp->mSampleTime + context->frames;
+
+    if ( (startTime.mFlags & kAudioTimeStampHostTimeValid && startTime.mHostTime > hostTimeAtBufferEnd)
+           || (startTime.mFlags & kAudioTimeStampSampleTimeValid && startTime.mSampleTime > sampleTimeAtBufferEnd) ) {
         // Start time not yet reached: emit silence
         AEAudioBufferListSilence(abl, 0, context->frames);
         return;
 
-    } else if ( startTime && startTime < context->timestamp->mHostTime ) {
+    } else if ( (startTime.mFlags & kAudioTimeStampHostTimeValid && startTime.mHostTime < context->timestamp->mHostTime)
+           || (startTime.mFlags & kAudioTimeStampSampleTimeValid && startTime.mSampleTime < context->timestamp->mSampleTime) ) {
         // Start time is in the past - we need to skip some frames
-        AEHostTicks skipTime = context->timestamp->mHostTime - startTime;
-        UInt32 skipFrames = round(AESecondsFromHostTicks(skipTime) * context->sampleRate);
+        UInt32 skipFrames =
+            startTime.mFlags & kAudioTimeStampHostTimeValid ?
+                round(AESecondsFromHostTicks(context->timestamp->mHostTime - startTime.mHostTime) * context->sampleRate)
+                : context->timestamp->mSampleTime - startTime.mSampleTime;
         playhead += (double)skipFrames * (THIS->_fileSampleRate / context->sampleRate);
         AudioTimeStamp timestamp = {
-            .mFlags = kAudioTimeStampSampleTimeValid|kAudioTimeStampHostTimeValid,
+            .mFlags = startTime.mFlags | kAudioTimeStampSampleTimeValid,
             .mSampleTime = context->timestamp->mSampleTime - skipFrames,
-            .mHostTime = startTime
+            .mHostTime = startTime.mHostTime
         };
 
         AEAudioBufferListCopyOnStack(scratch, abl, 0);
@@ -471,12 +477,16 @@ static void AEAudioFilePlayerModuleProcess(__unsafe_unretained AEAudioFilePlayer
         }
     }
 
-    THIS->_startTime = 0;
+    THIS->_startTime = AETimeStampNone;
 
     // Prepare buffer
     UInt32 frames = context->frames;
-    UInt32 silentFrames = startTime && startTime > context->timestamp->mHostTime
-        ? round(AESecondsFromHostTicks(startTime - context->timestamp->mHostTime) * context->sampleRate) : 0;
+    UInt32 silentFrames =
+        (startTime.mFlags & kAudioTimeStampHostTimeValid && startTime.mHostTime > context->timestamp->mHostTime)
+         ? round(AESecondsFromHostTicks(startTime.mHostTime - context->timestamp->mHostTime) * context->sampleRate)
+        : (startTime.mFlags & kAudioTimeStampSampleTimeValid && startTime.mSampleTime > context->timestamp->mSampleTime)
+         ? startTime.mSampleTime - context->timestamp->mSampleTime
+        : 0;
     AEAudioBufferListCopyOnStack(mutableAbl, abl, silentFrames);
     AudioTimeStamp adjustedTime = *context->timestamp;
 
@@ -486,7 +496,7 @@ static void AEAudioFilePlayerModuleProcess(__unsafe_unretained AEAudioFilePlayer
         // Point buffer list to remaining frames
         abl = mutableAbl;
         frames -= silentFrames;
-        adjustedTime.mHostTime = startTime;
+        adjustedTime.mHostTime += AEHostTicksFromSeconds((double)silentFrames / context->sampleRate);
         adjustedTime.mSampleTime += silentFrames;
     }