DSP: Move HRTF filter to DSP class chain

Signed-off-by: Christopher Snowhill <kode54@gmail.com>

Audio/Chain/BufferChain.h

@@ -12,6 +12,7 @@
 #import "ConverterNode.h"
 #import "DSPRubberbandNode.h"
 #import "DSPFSurroundNode.h"
+#import "DSPHRTFNode.h"
 #import "InputNode.h"
 
 @interface BufferChain : NSObject {
@@ -19,6 +20,7 @@
 	ConverterNode *converterNode;
 	DSPRubberbandNode *rubberbandNode;
 	DSPFSurroundNode *fsurroundNode;
+	DSPHRTFNode *hrtfNode;
 
 	NSURL *streamURL;
 	id userInfo;
@@ -79,6 +81,8 @@
 
 - (DSPFSurroundNode *)fsurround;
 
+- (DSPHRTFNode *)hrtf;
+
 - (double)secondsBuffered;
 
 - (void)sustainHDCD;

Audio/Chain/BufferChain.m

@@ -28,6 +28,7 @@
 
 		rubberbandNode = nil;
 		fsurroundNode = nil;
+		hrtfNode = nil;
 	}
 
 	return self;
@@ -41,8 +42,9 @@
 	converterNode = [[ConverterNode alloc] initWithController:self previous:inputNode];
 	rubberbandNode = [[DSPRubberbandNode alloc] initWithController:self previous:converterNode latency:0.03];
 	fsurroundNode = [[DSPFSurroundNode alloc] initWithController:self previous:rubberbandNode latency:0.03];
+	hrtfNode = [[DSPHRTFNode alloc] initWithController:self previous:fsurroundNode latency:0.03];
 
-	finalNode = fsurroundNode;
+	finalNode = hrtfNode;
 }
 
 - (BOOL)open:(NSURL *)url withOutputFormat:(AudioStreamBasicDescription)outputFormat withUserInfo:(id)userInfo withRGInfo:(NSDictionary *)rgi {
@@ -153,6 +155,7 @@
 	[converterNode launchThread];
 	[rubberbandNode launchThread];
 	[fsurroundNode launchThread];
+	[hrtfNode launchThread];
 }
 
 - (void)setUserInfo:(id)i {
@@ -222,6 +225,7 @@
 	[converterNode setShouldContinue:s];
 	[rubberbandNode setShouldContinue:s];
 	[fsurroundNode setShouldContinue:s];
+	[hrtfNode setShouldContinue:s];
 }
 
 - (BOOL)isRunning {
@@ -248,6 +252,10 @@
 	return fsurroundNode;
 }
 
+- (DSPHRTFNode *)hrtf {
+	return hrtfNode;
+}
+
 - (AudioStreamBasicDescription)inputFormat {
 	return [inputNode nodeFormat];
 }

Audio/Chain/DSP/DSPHRTFNode.h

@@ -0,0 +1,33 @@
+//
+//  DSPHRTFNode.h
+//  CogAudio
+//
+//  Created by Christopher Snowhill on 2/11/25.
+//
+
+#ifndef DSPHRTFNode_h
+#define DSPHRTFNode_h
+
+#import <simd/types.h>
+
+#import "DSPNode.h"
+
+@interface DSPHRTFNode : DSPNode {
+}
+
+- (id _Nullable)initWithController:(id _Nonnull)c previous:(id _Nullable)p latency:(double)latency;
+
+- (BOOL)setup;
+- (void)cleanUp;
+
+- (void)resetBuffer;
+
+- (void)process;
+- (AudioChunk * _Nullable)convert;
+
+- (void)reportMotion:(simd_float4x4)matrix;
+- (void)resetReferencePosition:(NSNotification *_Nullable)notification;
+
+@end
+
+#endif /* DSPHRTFNode_h */

Audio/Chain/DSP/DSPHRTFNode.m

@@ -0,0 +1,368 @@
+//
+//  DSPHRTFNode.m
+//  CogAudio Framework
+//
+//  Created by Christopher Snowhill on 2/11/25.
+//
+
+#import <Foundation/Foundation.h>
+
+#import <CoreMotion/CoreMotion.h>
+
+#import "Logging.h"
+
+#import "DSPHRTFNode.h"
+
+#import "HeadphoneFilter.h"
+
+static void * kDSPHRTFNodeContext = &kDSPHRTFNodeContext;
+
+static NSString *CogPlaybackDidResetHeadTracking = @"CogPlaybackDigResetHeadTracking";
+
+static simd_float4x4 convertMatrix(CMRotationMatrix r) {
+	simd_float4x4 matrix = {
+		simd_make_float4(r.m33, -r.m31, r.m32, 0.0f),
+		simd_make_float4(r.m13, -r.m11, r.m12, 0.0f),
+		simd_make_float4(r.m23, -r.m21, r.m22, 0.0f),
+		simd_make_float4(0.0f, 0.0f, 0.0f, 1.0f)
+	};
+	return matrix;
+}
+
+static NSLock *motionManagerLock = nil;
+API_AVAILABLE(macos(14.0)) static CMHeadphoneMotionManager *motionManager = nil;
+static DSPHRTFNode  *registeredMotionListener = nil;
+
+static void registerMotionListener(DSPHRTFNode *listener) {
+	if(@available(macOS 14, *)) {
+		[motionManagerLock lock];
+		if([motionManager isDeviceMotionActive]) {
+			[motionManager stopDeviceMotionUpdates];
+		}
+		if([motionManager isDeviceMotionAvailable]) {
+			registeredMotionListener = listener;
+			[motionManager startDeviceMotionUpdatesToQueue:[NSOperationQueue mainQueue] withHandler:^(CMDeviceMotion * _Nullable motion, NSError * _Nullable error) {
+				if(motion) {
+					[motionManagerLock lock];
+					[registeredMotionListener reportMotion:convertMatrix(motion.attitude.rotationMatrix)];
+					[motionManagerLock unlock];
+				}
+			}];
+		}
+		[motionManagerLock unlock];
+	}
+}
+
+static void unregisterMotionListener(void) {
+	if(@available(macOS 14, *)) {
+		[motionManagerLock lock];
+		if([motionManager isDeviceMotionActive]) {
+			[motionManager stopDeviceMotionUpdates];
+		}
+		registeredMotionListener = nil;
+		[motionManagerLock unlock];
+	}
+}
+
+@implementation DSPHRTFNode {
+	BOOL enableHrtf;
+	BOOL enableHeadTracking;
+	BOOL lastEnableHeadTracking;
+
+	HeadphoneFilter *hrtf;
+
+	BOOL stopping, paused;
+	BOOL processEntered;
+	BOOL resetFilter;
+
+	BOOL observersapplied;
+
+	AudioStreamBasicDescription lastInputFormat;
+	AudioStreamBasicDescription inputFormat;
+	AudioStreamBasicDescription outputFormat;
+
+	uint32_t lastInputChannelConfig, inputChannelConfig;
+	uint32_t outputChannelConfig;
+
+	BOOL referenceMatrixSet;
+	BOOL rotationMatrixUpdated;
+	simd_float4x4 rotationMatrix;
+	simd_float4x4 referenceMatrix;
+
+	float outBuffer[4096 * 2];
+}
+
++ (void)initialize {
+	motionManagerLock = [[NSLock alloc] init];
+
+	if(@available(macOS 14, *)) {
+		CMAuthorizationStatus status = [CMHeadphoneMotionManager authorizationStatus];
+		if(status == CMAuthorizationStatusDenied) {
+			ALog(@"Headphone motion not authorized");
+			return;
+		} else if(status == CMAuthorizationStatusAuthorized) {
+			ALog(@"Headphone motion authorized");
+		} else if(status == CMAuthorizationStatusRestricted) {
+			ALog(@"Headphone motion restricted");
+		} else if(status == CMAuthorizationStatusNotDetermined) {
+			ALog(@"Headphone motion status not determined; will prompt for access");
+		}
+
+		motionManager = [[CMHeadphoneMotionManager alloc] init];
+	}
+}
+
+- (id _Nullable)initWithController:(id _Nonnull)c previous:(id _Nullable)p latency:(double)latency {
+	self = [super initWithController:c previous:p latency:latency];
+	if(self) {
+		NSUserDefaults *defaults = [[NSUserDefaultsController sharedUserDefaultsController] defaults];
+		enableHrtf = [defaults boolForKey:@"enableHrtf"];
+		enableHeadTracking = [defaults boolForKey:@"enableHeadTracking"];
+
+		rotationMatrix = matrix_identity_float4x4;
+
+		[self addObservers];
+	}
+	return self;
+}
+
+- (void)dealloc {
+	[self cleanUp];
+	[self removeObservers];
+}
+
+- (void)addObservers {
+	[[NSUserDefaultsController sharedUserDefaultsController] addObserver:self forKeyPath:@"values.enableHrtf" options:(NSKeyValueObservingOptionInitial | NSKeyValueObservingOptionNew) context:kDSPHRTFNodeContext];
+	[[NSUserDefaultsController sharedUserDefaultsController] addObserver:self forKeyPath:@"values.enableHeadTracking" options:(NSKeyValueObservingOptionInitial | NSKeyValueObservingOptionNew) context:kDSPHRTFNodeContext];
+
+	[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(resetReferencePosition:) name:CogPlaybackDidResetHeadTracking object:nil];
+
+	observersapplied = YES;
+}
+
+- (void)removeObservers {
+	if(observersapplied) {
+		[[NSUserDefaultsController sharedUserDefaultsController] removeObserver:self forKeyPath:@"values.enableHrtf" context:kDSPHRTFNodeContext];
+		[[NSUserDefaultsController sharedUserDefaultsController] removeObserver:self forKeyPath:@"values.enableHeadTracking" context:kDSPHRTFNodeContext];
+
+		[[NSNotificationCenter defaultCenter] removeObserver:self name:CogPlaybackDidResetHeadTracking object:nil];
+
+		observersapplied = NO;
+	}
+}
+
+- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
+	if(context != kDSPHRTFNodeContext) {
+		[super observeValueForKeyPath:keyPath ofObject:object change:change context:context];
+		return;
+	}
+
+	if([keyPath isEqualToString:@"values.enableHrtf"] ||
+	   [keyPath isEqualToString:@"values.enableHeadTracking"]) {
+		NSUserDefaults *defaults = [[NSUserDefaultsController sharedUserDefaultsController] defaults];
+		enableHrtf = [defaults boolForKey:@"enableHrtf"];
+		enableHeadTracking = [defaults boolForKey:@"enableHeadTracking"];
+		resetFilter = YES;
+	}
+}
+
+- (BOOL)fullInit {
+	if(enableHrtf) {
+		NSURL *presetUrl = [[NSBundle mainBundle] URLForResource:@"SADIE_D02-96000" withExtension:@"mhr"];
+
+		rotationMatrixUpdated = NO;
+
+		simd_float4x4 matrix;
+		if(!referenceMatrixSet || !enableHeadTracking) {
+			referenceMatrixSet = NO;
+			matrix = matrix_identity_float4x4;
+			self->referenceMatrix = matrix;
+			if(enableHeadTracking) {
+				lastEnableHeadTracking = YES;
+				registerMotionListener(self);
+			} else if(lastEnableHeadTracking) {
+				lastEnableHeadTracking = NO;
+				unregisterMotionListener();
+			}
+		} else {
+			simd_float4x4 mirrorTransform = {
+				simd_make_float4(-1.0, 0.0, 0.0, 0.0),
+				simd_make_float4(0.0, 1.0, 0.0, 0.0),
+				simd_make_float4(0.0, 0.0, 1.0, 0.0),
+				simd_make_float4(0.0, 0.0, 0.0, 1.0)
+			};
+
+			matrix = simd_mul(mirrorTransform, rotationMatrix);
+			matrix = simd_mul(matrix, referenceMatrix);
+		}
+
+		hrtf = [[HeadphoneFilter alloc] initWithImpulseFile:presetUrl forSampleRate:inputFormat.mSampleRate withInputChannels:inputFormat.mChannelsPerFrame withConfig:inputChannelConfig withMatrix:matrix];
+		if(!hrtf) {
+			return NO;
+		}
+
+		outputFormat = inputFormat;
+		outputFormat.mChannelsPerFrame = 2;
+		outputFormat.mBytesPerFrame = sizeof(float) * outputFormat.mChannelsPerFrame;
+		outputFormat.mBytesPerPacket = outputFormat.mBytesPerFrame * outputFormat.mFramesPerPacket;
+		outputChannelConfig = AudioChannelSideLeft | AudioChannelSideRight;
+
+		resetFilter = NO;
+	} else {
+		if(lastEnableHeadTracking) {
+			lastEnableHeadTracking = NO;
+			unregisterMotionListener();
+		}
+		referenceMatrixSet = NO;
+
+		hrtf = nil;
+	}
+
+	return YES;
+}
+
+- (void)fullShutdown {
+	hrtf = nil;
+	if(lastEnableHeadTracking) {
+		lastEnableHeadTracking = NO;
+		unregisterMotionListener();
+	}
+	resetFilter = NO;
+}
+
+- (BOOL)setup {
+	if(stopping)
+		return NO;
+	[self fullShutdown];
+	return [self fullInit];
+}
+
+- (void)cleanUp {
+	stopping = YES;
+	while(processEntered) {
+		usleep(1000);
+	}
+	[self fullShutdown];
+}
+
+- (void)resetBuffer {
+	paused = YES;
+	while(processEntered) {
+		usleep(500);
+	}
+	[super resetBuffer];
+	[self fullShutdown];
+	paused = NO;
+}
+
+- (void)process {
+	while([self shouldContinue] == YES) {
+		if(paused) {
+			usleep(500);
+			continue;
+		}
+		@autoreleasepool {
+			AudioChunk *chunk = nil;
+			chunk = [self convert];
+			if(!chunk) {
+				if([self endOfStream] == YES) {
+					break;
+				}
+				if(paused) {
+					continue;
+				}
+			} else {
+				[self writeChunk:chunk];
+				chunk = nil;
+			}
+			if(resetFilter || (!enableHrtf && hrtf)) {
+				[self fullShutdown];
+			}
+		}
+	}
+}
+
+- (AudioChunk *)convert {
+	if(stopping)
+		return nil;
+
+	processEntered = YES;
+
+	if(stopping || [self endOfStream] == YES || [self shouldContinue] == NO) {
+		processEntered = NO;
+		return nil;
+	}
+
+	if(![self peekFormat:&inputFormat channelConfig:&inputChannelConfig]) {
+		processEntered = NO;
+		return nil;
+	}
+
+	if((enableHrtf && !hrtf) ||
+	   memcmp(&inputFormat, &lastInputFormat, sizeof(inputFormat)) != 0 ||
+	   inputChannelConfig != lastInputChannelConfig) {
+		lastInputFormat = inputFormat;
+		lastInputChannelConfig = inputChannelConfig;
+		[self fullShutdown];
+		if(![self setup]) {
+			processEntered = NO;
+			return nil;
+		}
+	}
+
+	if(!hrtf) {
+		processEntered = NO;
+		return [self readChunk:4096];
+	}
+
+	AudioChunk *chunk = [self readChunkAsFloat32:4096];
+	if(!chunk) {
+		processEntered = NO;
+		return nil;
+	}
+
+	if(rotationMatrixUpdated) {
+		rotationMatrixUpdated = NO;
+		simd_float4x4 mirrorTransform = {
+			simd_make_float4(-1.0, 0.0, 0.0, 0.0),
+			simd_make_float4(0.0, 1.0, 0.0, 0.0),
+			simd_make_float4(0.0, 0.0, 1.0, 0.0),
+			simd_make_float4(0.0, 0.0, 0.0, 1.0)
+		};
+
+		simd_float4x4 matrix = simd_mul(mirrorTransform, rotationMatrix);
+		matrix = simd_mul(matrix, referenceMatrix);
+
+		[hrtf reloadWithMatrix:matrix];
+	}
+
+	size_t frameCount = [chunk frameCount];
+	NSData *sampleData = [chunk removeSamples:frameCount];
+
+	[hrtf process:(const float *)[sampleData bytes] sampleCount:(int)frameCount toBuffer:&outBuffer[0]];
+
+	AudioChunk *outputChunk = [[AudioChunk alloc] init];
+	[outputChunk setFormat:outputFormat];
+	if(outputChannelConfig) {
+		[outputChunk setChannelConfig:outputChannelConfig];
+	}
+	[outputChunk assignSamples:&outBuffer[0] frameCount:frameCount];
+
+	processEntered = NO;
+	return outputChunk;
+}
+
+- (void)reportMotion:(simd_float4x4)matrix {
+	rotationMatrix = matrix;
+	if(!referenceMatrixSet) {
+		referenceMatrix = simd_inverse(matrix);
+		referenceMatrixSet = YES;
+	}
+	rotationMatrixUpdated = YES;
+}
+
+- (void)resetReferencePosition:(NSNotification *)notification {
+	referenceMatrixSet = NO;
+}
+
+@end

Audio/Chain/InputNode.m

@@ -163,6 +163,7 @@ static void *kInputNodeContext = &kInputNodeContext;
 			ConverterNode *converter = [bufferChain converter];
 			DSPRubberbandNode *rubberband = [bufferChain rubberband];
 			DSPFSurroundNode *fsurround = [bufferChain fsurround];
+			DSPHRTFNode *hrtf = [bufferChain hrtf];
 			DLog(@"SEEKING! Resetting Buffer");
 
 			// This resets the converter's buffer
@@ -171,6 +172,7 @@ static void *kInputNodeContext = &kInputNodeContext;
 			[converter inputFormatDidChange:[bufferChain inputFormat] inputConfig:[bufferChain inputConfig]];
 			[rubberband resetBuffer];
 			[fsurround resetBuffer];
+			[hrtf resetBuffer];
 
 			DLog(@"Reset buffer!");
 

Audio/CogAudio.xcodeproj/project.pbxproj

@@ -89,8 +89,6 @@
 		839E56E72879450300DFB5F4 /* HrtfData.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 839E56E32879450300DFB5F4 /* HrtfData.cpp */; };
 		839E56E82879450300DFB5F4 /* IHrtfData.h in Headers */ = {isa = PBXBuildFile; fileRef = 839E56E42879450300DFB5F4 /* IHrtfData.h */; };
 		839E56EA28794F6300DFB5F4 /* HrtfTypes.h in Headers */ = {isa = PBXBuildFile; fileRef = 839E56E928794F6300DFB5F4 /* HrtfTypes.h */; };
-		839E56ED2879515D00DFB5F4 /* HeadphoneFilter.h in Headers */ = {isa = PBXBuildFile; fileRef = 839E56EB2879515D00DFB5F4 /* HeadphoneFilter.h */; };
-		839E56EE2879515D00DFB5F4 /* HeadphoneFilter.mm in Sources */ = {isa = PBXBuildFile; fileRef = 839E56EC2879515D00DFB5F4 /* HeadphoneFilter.mm */; };
 		839E56F7287974A100DFB5F4 /* SandboxBroker.h in Headers */ = {isa = PBXBuildFile; fileRef = 839E56F6287974A100DFB5F4 /* SandboxBroker.h */; };
 		83A3496A2D5C3F430096D530 /* DSPRubberbandNode.m in Sources */ = {isa = PBXBuildFile; fileRef = 83A349682D5C3F430096D530 /* DSPRubberbandNode.m */; };
 		83A3496B2D5C3F430096D530 /* DSPRubberbandNode.h in Headers */ = {isa = PBXBuildFile; fileRef = 83A349672D5C3F430096D530 /* DSPRubberbandNode.h */; };
@@ -98,7 +96,11 @@
 		83A3496F2D5C405E0096D530 /* DSPFSurroundNode.m in Sources */ = {isa = PBXBuildFile; fileRef = 83A3496E2D5C405E0096D530 /* DSPFSurroundNode.m */; };
 		83A349722D5C41810096D530 /* FSurroundFilter.mm in Sources */ = {isa = PBXBuildFile; fileRef = 83A349712D5C41810096D530 /* FSurroundFilter.mm */; };
 		83A349732D5C41810096D530 /* FSurroundFilter.h in Headers */ = {isa = PBXBuildFile; fileRef = 83A349702D5C41810096D530 /* FSurroundFilter.h */; };
+		83A349752D5C50A10096D530 /* DSPHRTFNode.h in Headers */ = {isa = PBXBuildFile; fileRef = 83A349742D5C50A10096D530 /* DSPHRTFNode.h */; };
+		83A349772D5C50B20096D530 /* DSPHRTFNode.m in Sources */ = {isa = PBXBuildFile; fileRef = 83A349762D5C50B20096D530 /* DSPHRTFNode.m */; };
 		83B74281289E027F005AAC28 /* CogAudio-Bridging-Header.h in Headers */ = {isa = PBXBuildFile; fileRef = 83B74280289E027F005AAC28 /* CogAudio-Bridging-Header.h */; };
+		83F843202D5C6272008C123B /* HeadphoneFilter.h in Headers */ = {isa = PBXBuildFile; fileRef = 83F8431E2D5C6272008C123B /* HeadphoneFilter.h */; };
+		83F843212D5C6272008C123B /* HeadphoneFilter.mm in Sources */ = {isa = PBXBuildFile; fileRef = 83F8431F2D5C6272008C123B /* HeadphoneFilter.mm */; };
 		83FFED512D5B08BC0044CCAF /* DSPNode.h in Headers */ = {isa = PBXBuildFile; fileRef = 83FFED502D5B08BC0044CCAF /* DSPNode.h */; };
 		83FFED532D5B09320044CCAF /* DSPNode.m in Sources */ = {isa = PBXBuildFile; fileRef = 83FFED522D5B09320044CCAF /* DSPNode.m */; };
 		8DC2EF570486A6940098B216 /* Cocoa.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 1058C7B1FEA5585E11CA2CBB /* Cocoa.framework */; };
@@ -209,8 +211,6 @@
 		839E56E32879450300DFB5F4 /* HrtfData.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = HrtfData.cpp; sourceTree = "<group>"; };
 		839E56E42879450300DFB5F4 /* IHrtfData.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = IHrtfData.h; sourceTree = "<group>"; };
 		839E56E928794F6300DFB5F4 /* HrtfTypes.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = HrtfTypes.h; sourceTree = "<group>"; };
-		839E56EB2879515D00DFB5F4 /* HeadphoneFilter.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = HeadphoneFilter.h; sourceTree = "<group>"; };
-		839E56EC2879515D00DFB5F4 /* HeadphoneFilter.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = HeadphoneFilter.mm; sourceTree = "<group>"; };
 		839E56F6287974A100DFB5F4 /* SandboxBroker.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = SandboxBroker.h; path = ../Utils/SandboxBroker.h; sourceTree = "<group>"; };
 		83A349672D5C3F430096D530 /* DSPRubberbandNode.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = DSPRubberbandNode.h; sourceTree = "<group>"; };
 		83A349682D5C3F430096D530 /* DSPRubberbandNode.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = DSPRubberbandNode.m; sourceTree = "<group>"; };
@@ -218,7 +218,11 @@
 		83A3496E2D5C405E0096D530 /* DSPFSurroundNode.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = DSPFSurroundNode.m; sourceTree = "<group>"; };
 		83A349702D5C41810096D530 /* FSurroundFilter.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = FSurroundFilter.h; sourceTree = "<group>"; };
 		83A349712D5C41810096D530 /* FSurroundFilter.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = FSurroundFilter.mm; sourceTree = "<group>"; };
+		83A349742D5C50A10096D530 /* DSPHRTFNode.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = DSPHRTFNode.h; sourceTree = "<group>"; };
+		83A349762D5C50B20096D530 /* DSPHRTFNode.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = DSPHRTFNode.m; sourceTree = "<group>"; };
 		83B74280289E027F005AAC28 /* CogAudio-Bridging-Header.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = "CogAudio-Bridging-Header.h"; sourceTree = "<group>"; };
+		83F8431E2D5C6272008C123B /* HeadphoneFilter.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = HeadphoneFilter.h; sourceTree = "<group>"; };
+		83F8431F2D5C6272008C123B /* HeadphoneFilter.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = HeadphoneFilter.mm; sourceTree = "<group>"; };
 		83FFED502D5B08BC0044CCAF /* DSPNode.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = DSPNode.h; sourceTree = "<group>"; };
 		83FFED522D5B09320044CCAF /* DSPNode.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = DSPNode.m; sourceTree = "<group>"; };
 		8DC2EF5A0486A6940098B216 /* Info.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist; path = Info.plist; sourceTree = "<group>"; };
@@ -385,8 +389,6 @@
 			children = (
 				835DD2662ACAF1D90057E319 /* OutputCoreAudio.h */,
 				835DD2652ACAF1D90057E319 /* OutputCoreAudio.m */,
-				839E56EB2879515D00DFB5F4 /* HeadphoneFilter.h */,
-				839E56EC2879515D00DFB5F4 /* HeadphoneFilter.mm */,
 			);
 			path = Output;
 			sourceTree = "<group>";
@@ -526,12 +528,16 @@
 		83A349692D5C3F430096D530 /* DSP */ = {
 			isa = PBXGroup;
 			children = (
+				83F8431E2D5C6272008C123B /* HeadphoneFilter.h */,
+				83F8431F2D5C6272008C123B /* HeadphoneFilter.mm */,
 				83A349702D5C41810096D530 /* FSurroundFilter.h */,
 				83A349712D5C41810096D530 /* FSurroundFilter.mm */,
 				83A349672D5C3F430096D530 /* DSPRubberbandNode.h */,
 				83A349682D5C3F430096D530 /* DSPRubberbandNode.m */,
 				83A3496C2D5C40490096D530 /* DSPFSurroundNode.h */,
 				83A3496E2D5C405E0096D530 /* DSPFSurroundNode.m */,
+				83A349742D5C50A10096D530 /* DSPHRTFNode.h */,
+				83A349762D5C50B20096D530 /* DSPHRTFNode.m */,
 			);
 			path = DSP;
 			sourceTree = "<group>";
@@ -544,6 +550,7 @@
 			buildActionMask = 2147483647;
 			files = (
 				839E56E82879450300DFB5F4 /* IHrtfData.h in Headers */,
+				83F843202D5C6272008C123B /* HeadphoneFilter.h in Headers */,
 				17D21CA10B8BE4BA00D1EBDE /* BufferChain.h in Headers */,
 				83A3496D2D5C40490096D530 /* DSPFSurroundNode.h in Headers */,
 				831A50142865A7FD0049CFE4 /* rsstate.hpp in Headers */,
@@ -564,11 +571,11 @@
 				839E56E62879450300DFB5F4 /* Endianness.h in Headers */,
 				17D21DC70B8BE79700D1EBDE /* CoreAudioUtils.h in Headers */,
 				835DD2722ACAF5AD0057E319 /* lpc.h in Headers */,
-				839E56ED2879515D00DFB5F4 /* HeadphoneFilter.h in Headers */,
 				17D21EBD0B8BF44000D1EBDE /* AudioPlayer.h in Headers */,
 				831A50182865A8B30049CFE4 /* rsstate.h in Headers */,
 				834FD4F027AF93680063BC83 /* ChunkList.h in Headers */,
 				17F94DD50B8D0F7000A34E87 /* PluginController.h in Headers */,
+				83A349752D5C50A10096D530 /* DSPHRTFNode.h in Headers */,
 				17F94DDD0B8D101100A34E87 /* Plugin.h in Headers */,
 				8328995727CB51B700D7F028 /* SHA256Digest.h in Headers */,
 				834FD4EB27AF8F380063BC83 /* AudioChunk.h in Headers */,
@@ -668,9 +675,9 @@
 			buildActionMask = 2147483647;
 			files = (
 				17D21CA20B8BE4BA00D1EBDE /* BufferChain.m in Sources */,
+				83A349772D5C50B20096D530 /* DSPHRTFNode.m in Sources */,
 				17D21CA60B8BE4BA00D1EBDE /* InputNode.m in Sources */,
 				83A3496A2D5C3F430096D530 /* DSPRubberbandNode.m in Sources */,
-				839E56EE2879515D00DFB5F4 /* HeadphoneFilter.mm in Sources */,
 				83504166286447DA006B32CC /* Downmix.m in Sources */,
 				8399CF2D27B5D1D5008751F1 /* NSDictionary+Merge.m in Sources */,
 				834A41AB287A90AB00EB9D9B /* channelmaps.cpp in Sources */,
@@ -695,6 +702,7 @@
 				8328995827CB51B700D7F028 /* SHA256Digest.m in Sources */,
 				17C940240B900909008627D6 /* AudioMetadataReader.m in Sources */,
 				17B619310B909BC300BC003F /* AudioPropertiesReader.m in Sources */,
+				83F843212D5C6272008C123B /* HeadphoneFilter.mm in Sources */,
 				17ADB13D0B97926D00257CA2 /* AudioSource.m in Sources */,
 				834FD4F127AF93680063BC83 /* ChunkList.m in Sources */,
 				83FFED532D5B09320044CCAF /* DSPNode.m in Sources */,

Audio/Output/OutputCoreAudio.h

@@ -70,9 +70,6 @@ using std::atomic_long;
 	BOOL eqEnabled;
 	BOOL eqInitialized;
 
-	BOOL enableHeadTracking;
-	BOOL lastEnableHeadTracking;
-
 	BOOL streamFormatStarted;
 	BOOL streamFormatChanged;
 
@@ -82,7 +79,6 @@ using std::atomic_long;
 	BOOL currentdevicelistenerapplied;
 	BOOL devicealivelistenerapplied;
 	BOOL observersapplied;
-	BOOL htlistenerapplied;
 	BOOL outputdevicechanged;
 
 	float volume;
@@ -114,9 +110,6 @@ using std::atomic_long;
 
 	VisualizationController *visController;
 
-	BOOL enableHrtf;
-	HeadphoneFilter *hrtf;
-	
 	int inputBufferLastTime;
 	
 	int inputRemain;
@@ -132,7 +125,6 @@ using std::atomic_long;
 	float *samplePtr;
 	float tempBuffer[512 * 32];
 	float inputBuffer[4096 * 32]; // 4096 samples times maximum supported channel count
-	float hrtfBuffer[4096 * 2];
 	float eqBuffer[4096 * 32];
 	float eqOutBuffer[4096 * 32];
 	float downmixBuffer[4096 * 8];
@@ -141,10 +133,6 @@ using std::atomic_long;
 	float visResamplerInput[8192];
 	float visTemp[8192];
 
-	BOOL referenceMatrixSet;
-	BOOL rotationMatrixUpdated;
-	simd_float4x4 rotationMatrix;
-	simd_float4x4 referenceMatrix;
 
 #ifdef OUTPUT_LOG
 	FILE *_logFile;
@@ -171,9 +159,4 @@ using std::atomic_long;
 
 - (void)sustainHDCD;
 
-- (void)reportMotion:(simd_float4x4)matrix;
-- (void)resetReferencePosition:(NSNotification *)notification;
-
-- (void)setTempo:(double)t;
-
 @end

Audio/Output/OutputCoreAudio.m

@@ -17,81 +17,13 @@
 
 #import <Accelerate/Accelerate.h>
 
-#import <CoreMotion/CoreMotion.h>
-
 #import "rsstate.h"
 
 extern void scale_by_volume(float *buffer, size_t count, float volume);
 
 static NSString *CogPlaybackDidBeginNotificiation = @"CogPlaybackDidBeginNotificiation";
 
-static NSString *CogPlaybackDidResetHeadTracking = @"CogPlaybackDigResetHeadTracking";
-
-simd_float4x4 convertMatrix(CMRotationMatrix r) {
-	simd_float4x4 matrix = {
-		simd_make_float4(r.m33, -r.m31, r.m32, 0.0f),
-		simd_make_float4(r.m13, -r.m11, r.m12, 0.0f),
-		simd_make_float4(r.m23, -r.m21, r.m22, 0.0f),
-		simd_make_float4(0.0f, 0.0f, 0.0f, 1.0f)
-	};
-	return matrix;
-}
-
-NSLock *motionManagerLock = nil;
-API_AVAILABLE(macos(14.0)) CMHeadphoneMotionManager *motionManager = nil;
-OutputCoreAudio *registeredMotionListener = nil;
-
 @implementation OutputCoreAudio
-+ (void)initialize {
-	motionManagerLock = [[NSLock alloc] init];
-
-	if(@available(macOS 14, *)) {
-		CMAuthorizationStatus status = [CMHeadphoneMotionManager authorizationStatus];
-		if(status == CMAuthorizationStatusDenied) {
-			ALog(@"Headphone motion not authorized");
-			return;
-		} else if(status == CMAuthorizationStatusAuthorized) {
-			ALog(@"Headphone motion authorized");
-		} else if(status == CMAuthorizationStatusRestricted) {
-			ALog(@"Headphone motion restricted");
-		} else if(status == CMAuthorizationStatusNotDetermined) {
-			ALog(@"Headphone motion status not determined; will prompt for access");
-		}
-
-		motionManager = [[CMHeadphoneMotionManager alloc] init];
-	}
-}
-
-void registerMotionListener(OutputCoreAudio *listener) {
-	if(@available(macOS 14, *)) {
-		[motionManagerLock lock];
-		if([motionManager isDeviceMotionActive]) {
-			[motionManager stopDeviceMotionUpdates];
-		}
-		if([motionManager isDeviceMotionAvailable]) {
-			registeredMotionListener = listener;
-			[motionManager startDeviceMotionUpdatesToQueue:[NSOperationQueue mainQueue] withHandler:^(CMDeviceMotion * _Nullable motion, NSError * _Nullable error) {
-				if(motion) {
-					[motionManagerLock lock];
-					[registeredMotionListener reportMotion:convertMatrix(motion.attitude.rotationMatrix)];
-					[motionManagerLock unlock];
-				}
-			}];
-		}
-		[motionManagerLock unlock];
-	}
-}
-
-void unregisterMotionListener(void) {
-	if(@available(macOS 14, *)) {
-		[motionManagerLock lock];
-		if([motionManager isDeviceMotionActive]) {
-			[motionManager stopDeviceMotionUpdates];
-		}
-		registeredMotionListener = nil;
-		[motionManagerLock unlock];
-	}
-}
 
 static void *kOutputCoreAudioContext = &kOutputCoreAudioContext;
 
@@ -143,28 +75,12 @@ static OSStatus eqRenderCallback(void *inRefCon, AudioUnitRenderActionFlags *ioA
 		origFormat = format;
 
 		UInt32 srcChannels = format.mChannelsPerFrame;
-		uint32_t dmConfig = config;
-		uint32_t dmChannels = srcChannels;
-		AudioStreamBasicDescription dmFormat;
-		dmFormat = format;
-		[outputLock lock];
-		if(hrtf) {
-			dmChannels = 2;
-			dmConfig = AudioChannelFrontLeft | AudioChannelFrontRight;
-		}
-		[outputLock unlock];
-		if(dmChannels != srcChannels) {
-			dmFormat.mChannelsPerFrame = dmChannels;
-			dmFormat.mBytesPerFrame = ((dmFormat.mBitsPerChannel + 7) / 8) * dmChannels;
-			dmFormat.mBytesPerPacket = dmFormat.mBytesPerFrame * dmFormat.mFramesPerPacket;
-		}
 		UInt32 dstChannels = deviceFormat.mChannelsPerFrame;
-		if(dmChannels != dstChannels) {
+		if(srcChannels != dstChannels) {
 			format.mChannelsPerFrame = dstChannels;
 			format.mBytesPerFrame = ((format.mBitsPerChannel + 7) / 8) * dstChannels;
 			format.mBytesPerPacket = format.mBytesPerFrame * format.mFramesPerPacket;
-			downmixer = [[DownmixProcessor alloc] initWithInputFormat:dmFormat inputConfig:dmConfig andOutputFormat:format outputConfig:deviceChannelConfig];
-			format = origFormat;
+			downmixer = [[DownmixProcessor alloc] initWithInputFormat:origFormat inputConfig:origConfig andOutputFormat:format outputConfig:deviceChannelConfig];
 		} else {
 			downmixer = nil;
 		}
@@ -383,12 +299,6 @@ current_device_listener(AudioObjectID inObjectID, UInt32 inNumberAddresses, cons
 	} else if([keyPath isEqualToString:@"values.eqPreamp"]) {
 		float preamp = [[[NSUserDefaultsController sharedUserDefaultsController] defaults] floatForKey:@"eqPreamp"];
 		eqPreamp = pow(10.0, preamp / 20.0);
-	} else if([keyPath isEqualToString:@"values.enableHrtf"] ||
-			  [keyPath isEqualToString:@"values.enableHeadTracking"]) {
-		enableHrtf = [[[NSUserDefaultsController sharedUserDefaultsController] defaults] boolForKey:@"enableHrtf"];
-		enableHeadTracking = [[[NSUserDefaultsController sharedUserDefaultsController] defaults] boolForKey:@"enableHeadTracking"];
-		if(streamFormatStarted)
-			resetStreamFormat = YES;
 	} else if([keyPath isEqualToString:@"values.tempo"]) {
 		tempo = [[[NSUserDefaultsController sharedUserDefaultsController] defaults] doubleForKey:@"tempo"];
 	}
@@ -763,53 +673,6 @@ current_device_listener(AudioObjectID inObjectID, UInt32 inNumberAddresses, cons
 	uint32_t channels = realStreamFormat.mChannelsPerFrame;
 	uint32_t channelConfig = realStreamChannelConfig;
 
-	if(enableHrtf) {
-		NSURL *presetUrl = [[NSBundle mainBundle] URLForResource:@"SADIE_D02-96000" withExtension:@"mhr"];
-
-		rotationMatrixUpdated = NO;
-
-		simd_float4x4 matrix;
-		if(!referenceMatrixSet || !enableHeadTracking) {
-			referenceMatrixSet = NO;
-			matrix = matrix_identity_float4x4;
-			self->referenceMatrix = matrix;
-			if(enableHeadTracking) {
-				lastEnableHeadTracking = YES;
-				registerMotionListener(self);
-			} else if(lastEnableHeadTracking) {
-				lastEnableHeadTracking = NO;
-				unregisterMotionListener();
-			}
-		} else {
-			simd_float4x4 mirrorTransform = {
-				simd_make_float4(-1.0, 0.0, 0.0, 0.0),
-				simd_make_float4(0.0, 1.0, 0.0, 0.0),
-				simd_make_float4(0.0, 0.0, 1.0, 0.0),
-				simd_make_float4(0.0, 0.0, 0.0, 1.0)
-			};
-
-			matrix = simd_mul(mirrorTransform, rotationMatrix);
-			matrix = simd_mul(matrix, referenceMatrix);
-		}
-
-		[outputLock lock];
-		hrtf = [[HeadphoneFilter alloc] initWithImpulseFile:presetUrl forSampleRate:realStreamFormat.mSampleRate withInputChannels:channels withConfig:channelConfig withMatrix:matrix];
-		[outputLock unlock];
-
-		channels = 2;
-		channelConfig = AudioChannelSideLeft | AudioChannelSideRight;
-	} else {
-		if(lastEnableHeadTracking) {
-			lastEnableHeadTracking = NO;
-			unregisterMotionListener();
-		}
-		referenceMatrixSet = NO;
-
-		[outputLock lock];
-		hrtf = nil;
-		[outputLock unlock];
-	}
-
 	streamFormat = realStreamFormat;
 	streamFormat.mChannelsPerFrame = channels;
 	streamFormat.mBytesPerFrame = sizeof(float) * channels;
@@ -932,27 +795,6 @@ current_device_listener(AudioObjectID inObjectID, UInt32 inNumberAddresses, cons
 	samplePtr = &inputBuffer[0];
 
 	if(samplesRendered) {
-		[outputLock lock];
-		if(hrtf) {
-			if(rotationMatrixUpdated) {
-				rotationMatrixUpdated = NO;
-				simd_float4x4 mirrorTransform = {
-					simd_make_float4(-1.0, 0.0, 0.0, 0.0),
-					simd_make_float4(0.0, 1.0, 0.0, 0.0),
-					simd_make_float4(0.0, 0.0, 1.0, 0.0),
-					simd_make_float4(0.0, 0.0, 0.0, 1.0)
-				};
-
-				simd_float4x4 matrix = simd_mul(mirrorTransform, rotationMatrix);
-				matrix = simd_mul(matrix, referenceMatrix);
-
-				[hrtf reloadWithMatrix:matrix];
-			}
-			[hrtf process:samplePtr sampleCount:samplesRendered toBuffer:&hrtfBuffer[0]];
-			samplePtr = &hrtfBuffer[0];
-		}
-		[outputLock unlock];
-
 		if(eqEnabled && eqInitialized) {
 			const int channels = streamFormat.mChannelsPerFrame;
 			if(channels > 0) {
@@ -1091,9 +933,6 @@ current_device_listener(AudioObjectID inObjectID, UInt32 inNumberAddresses, cons
 		secondsLatency = 0;
 		visPushed = 0;
 
-		referenceMatrixSet = NO;
-		rotationMatrix = matrix_identity_float4x4;
-
 		AudioComponentDescription desc;
 		NSError *err;
 
@@ -1177,15 +1016,10 @@ current_device_listener(AudioObjectID inObjectID, UInt32 inNumberAddresses, cons
 		[[NSUserDefaultsController sharedUserDefaultsController] addObserver:self forKeyPath:@"values.outputDevice" options:0 context:kOutputCoreAudioContext];
 		[[NSUserDefaultsController sharedUserDefaultsController] addObserver:self forKeyPath:@"values.GraphicEQenable" options:0 context:kOutputCoreAudioContext];
 		[[NSUserDefaultsController sharedUserDefaultsController] addObserver:self forKeyPath:@"values.eqPreamp" options:(NSKeyValueObservingOptionInitial | NSKeyValueObservingOptionNew) context:kOutputCoreAudioContext];
-		[[NSUserDefaultsController sharedUserDefaultsController] addObserver:self forKeyPath:@"values.enableHrtf" options:(NSKeyValueObservingOptionInitial | NSKeyValueObservingOptionNew) context:kOutputCoreAudioContext];
-		[[NSUserDefaultsController sharedUserDefaultsController] addObserver:self forKeyPath:@"values.enableHeadTracking" options:(NSKeyValueObservingOptionInitial | NSKeyValueObservingOptionNew) context:kOutputCoreAudioContext];
 		[[NSUserDefaultsController sharedUserDefaultsController] addObserver:self forKeyPath:@"values.tempo" options:(NSKeyValueObservingOptionInitial | NSKeyValueObservingOptionNew) context:kOutputCoreAudioContext];
 
 		observersapplied = YES;
 
-		[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(resetReferencePosition:) name:CogPlaybackDidResetHeadTracking object:nil];
-		htlistenerapplied = YES;
-
 		bzero(&timeStamp, sizeof(timeStamp));
 		timeStamp.mFlags = kAudioTimeStampSampleTimeValid;
 
@@ -1243,20 +1077,10 @@ current_device_listener(AudioObjectID inObjectID, UInt32 inNumberAddresses, cons
 	}
 	@synchronized(self) {
 		stopInvoked = YES;
-		if(hrtf && lastEnableHeadTracking) {
-			lastEnableHeadTracking = NO;
-			unregisterMotionListener();
-		}
-		if(htlistenerapplied) {
-			[[NSNotificationCenter defaultCenter] removeObserver:self name:CogPlaybackDidResetHeadTracking object:nil];
-			htlistenerapplied = NO;
-		}
 		if(observersapplied) {
 			[[NSUserDefaultsController sharedUserDefaultsController] removeObserver:self forKeyPath:@"values.outputDevice" context:kOutputCoreAudioContext];
 			[[NSUserDefaultsController sharedUserDefaultsController] removeObserver:self forKeyPath:@"values.GraphicEQenable" context:kOutputCoreAudioContext];
 			[[NSUserDefaultsController sharedUserDefaultsController] removeObserver:self forKeyPath:@"values.eqPreamp" context:kOutputCoreAudioContext];
-			[[NSUserDefaultsController sharedUserDefaultsController] removeObserver:self forKeyPath:@"values.enableHrtf" context:kOutputCoreAudioContext];
-			[[NSUserDefaultsController sharedUserDefaultsController] removeObserver:self forKeyPath:@"values.enableHeadTracking" context:kOutputCoreAudioContext];
 			[[NSUserDefaultsController sharedUserDefaultsController] removeObserver:self forKeyPath:@"values.tempo" context:kOutputCoreAudioContext];
 			observersapplied = NO;
 		}
@@ -1360,17 +1184,4 @@ current_device_listener(AudioObjectID inObjectID, UInt32 inNumberAddresses, cons
 	shouldPlayOutBuffer = s;
 }
 
-- (void)reportMotion:(simd_float4x4)matrix {
-	rotationMatrix = matrix;
-	if(!referenceMatrixSet) {
-		referenceMatrix = simd_inverse(matrix);
-		referenceMatrixSet = YES;
-	}
-	rotationMatrixUpdated = YES;
-}
-
-- (void)resetReferencePosition:(NSNotification *)notification {
-	referenceMatrixSet = NO;
-}
-
 @end