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Modernization #7

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965c2c4
Project file updated by Xcode 12.4.
Sep 23, 2021
b2b437c
Rewrite using .withUnsafeMutableBufferPointer API for creating DSPDou…
Sep 23, 2021
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33 changes: 29 additions & 4 deletions ffttest.xcodeproj/project.pbxproj
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -3,7 +3,7 @@
archiveVersion = 1;
classes = {
};
objectVersion = 46;
objectVersion = 50;
objects = {

/* Begin PBXBuildFile section */
Expand Down Expand Up @@ -47,6 +47,7 @@
9D149E461B82226B00FF68B2 /* Products */,
);
sourceTree = "<group>";
usesTabs = 0;
};
9D149E461B82226B00FF68B2 /* Products */ = {
isa = PBXGroup;
Expand Down Expand Up @@ -91,7 +92,7 @@
9D149E3D1B82226B00FF68B2 /* Project object */ = {
isa = PBXProject;
attributes = {
LastUpgradeCheck = 0830;
LastUpgradeCheck = 1240;
ORGANIZATIONNAME = "Christopher Helf";
TargetAttributes = {
9D149E441B82226B00FF68B2 = {
Expand All @@ -101,10 +102,11 @@
};
};
buildConfigurationList = 9D149E401B82226B00FF68B2 /* Build configuration list for PBXProject "ffttest" */;
compatibilityVersion = "Xcode 5.2";
compatibilityVersion = "Xcode 9.3";
developmentRegion = English;
hasScannedForEncodings = 0;
knownRegions = (
English,
en,
);
mainGroup = 9D149E3C1B82226B00FF68B2;
Expand Down Expand Up @@ -134,18 +136,28 @@
isa = XCBuildConfiguration;
buildSettings = {
ALWAYS_SEARCH_USER_PATHS = NO;
CLANG_ANALYZER_LOCALIZABILITY_NONLOCALIZED = YES;
CLANG_CXX_LANGUAGE_STANDARD = "gnu++0x";
CLANG_CXX_LIBRARY = "libc++";
CLANG_ENABLE_MODULES = YES;
CLANG_ENABLE_OBJC_ARC = YES;
CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
CLANG_WARN_BOOL_CONVERSION = YES;
CLANG_WARN_COMMA = YES;
CLANG_WARN_CONSTANT_CONVERSION = YES;
CLANG_WARN_DEPRECATED_OBJC_IMPLEMENTATIONS = YES;
CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
CLANG_WARN_EMPTY_BODY = YES;
CLANG_WARN_ENUM_CONVERSION = YES;
CLANG_WARN_INFINITE_RECURSION = YES;
CLANG_WARN_INT_CONVERSION = YES;
CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
CLANG_WARN_OBJC_IMPLICIT_RETAIN_SELF = YES;
CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
CLANG_WARN_QUOTED_INCLUDE_IN_FRAMEWORK_HEADER = YES;
CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
CLANG_WARN_STRICT_PROTOTYPES = YES;
CLANG_WARN_SUSPICIOUS_MOVE = YES;
CLANG_WARN_UNREACHABLE_CODE = YES;
CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
Expand Down Expand Up @@ -180,18 +192,28 @@
isa = XCBuildConfiguration;
buildSettings = {
ALWAYS_SEARCH_USER_PATHS = NO;
CLANG_ANALYZER_LOCALIZABILITY_NONLOCALIZED = YES;
CLANG_CXX_LANGUAGE_STANDARD = "gnu++0x";
CLANG_CXX_LIBRARY = "libc++";
CLANG_ENABLE_MODULES = YES;
CLANG_ENABLE_OBJC_ARC = YES;
CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
CLANG_WARN_BOOL_CONVERSION = YES;
CLANG_WARN_COMMA = YES;
CLANG_WARN_CONSTANT_CONVERSION = YES;
CLANG_WARN_DEPRECATED_OBJC_IMPLEMENTATIONS = YES;
CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
CLANG_WARN_EMPTY_BODY = YES;
CLANG_WARN_ENUM_CONVERSION = YES;
CLANG_WARN_INFINITE_RECURSION = YES;
CLANG_WARN_INT_CONVERSION = YES;
CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
CLANG_WARN_OBJC_IMPLICIT_RETAIN_SELF = YES;
CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
CLANG_WARN_QUOTED_INCLUDE_IN_FRAMEWORK_HEADER = YES;
CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
CLANG_WARN_STRICT_PROTOTYPES = YES;
CLANG_WARN_SUSPICIOUS_MOVE = YES;
CLANG_WARN_UNREACHABLE_CODE = YES;
CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
Expand All @@ -210,13 +232,15 @@
MACOSX_DEPLOYMENT_TARGET = 10.12;
MTL_ENABLE_DEBUG_INFO = NO;
SDKROOT = macosx;
SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
SWIFT_COMPILATION_MODE = wholemodule;
SWIFT_OPTIMIZATION_LEVEL = "-O";
};
name = Release;
};
9D149E4D1B82226B00FF68B2 /* Debug */ = {
isa = XCBuildConfiguration;
buildSettings = {
CODE_SIGN_IDENTITY = "-";
PRODUCT_NAME = "$(TARGET_NAME)";
SWIFT_VERSION = 5.2;
};
Expand All @@ -225,6 +249,7 @@
9D149E4E1B82226B00FF68B2 /* Release */ = {
isa = XCBuildConfiguration;
buildSettings = {
CODE_SIGN_IDENTITY = "-";
PRODUCT_NAME = "$(TARGET_NAME)";
SWIFT_VERSION = 5.2;
};
Expand Down
243 changes: 127 additions & 116 deletions ffttest/fft.swift
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -73,125 +73,136 @@ class FFT {

var tempSplitComplexReal : [Double] = [Double](repeating: 0.0, count: N/2)
var tempSplitComplexImag : [Double] = [Double](repeating: 0.0, count: N/2)
var tempSplitComplex : DSPDoubleSplitComplex = DSPDoubleSplitComplex(realp: &tempSplitComplexReal, imagp: &tempSplitComplexImag)

// For polar coordinates
var mag : [Double] = [Double](repeating: 0.0, count: N/2)
var phase : [Double] = [Double](repeating: 0.0, count: N/2)

// ----------------------------------------------------------------
// Forward FFT
// ----------------------------------------------------------------

var valuesAsComplex : UnsafeMutablePointer<DSPDoubleComplex>? = nil

values.withUnsafeMutableBytes {
valuesAsComplex = $0.baseAddress?.bindMemory(to: DSPDoubleComplex.self, capacity: values1.count)
}

// Scramble-pack the real data into complex buffer in just the way that's
// required by the real-to-complex FFT function that follows.
vDSP_ctozD(valuesAsComplex!, 2, &tempSplitComplex, 1, N2);

// Do real->complex forward FFT
vDSP_fft_zripD(fftSetup, &tempSplitComplex, 1, LOG_N, FFTDirection(FFT_FORWARD));

// ----------------------------------------------------------------
// Get the Frequency Spectrum
// ----------------------------------------------------------------

var fftMagnitudes = [Double](repeating: 0.0, count: N/2)
vDSP_zvmagsD(&tempSplitComplex, 1, &fftMagnitudes, 1, N2);

// vDSP_zvmagsD returns squares of the FFT magnitudes, so take the root here
let roots = sqrt(fftMagnitudes)

// Normalize the Amplitudes
var fullSpectrum = [Double](repeating: 0.0, count: N/2)
vDSP_vsmulD(roots, vDSP_Stride(1), [1.0 / Double(N)], &fullSpectrum, 1, N2)

// ----------------------------------------------------------------
// Convert from complex/rectangular (real, imaginary) coordinates
// to polar (magnitude and phase) coordinates.
// ----------------------------------------------------------------

vDSP_zvabsD(&tempSplitComplex, 1, &mag, 1, N2);

// Beware: Outputted phase here between -PI and +PI
// https://developer.apple.com/library/prerelease/ios/documentation/Accelerate/Reference/vDSPRef/index.html#//apple_ref/c/func/vDSP_zvphasD
vDSP_zvphasD(&tempSplitComplex, 1, &phase, 1, N2);

// For polar coordinates
var mag : [Double] = [Double](repeating: 0.0, count: N/2)
var phase : [Double] = [Double](repeating: 0.0, count: N/2)

tempSplitComplexReal.withUnsafeMutableBufferPointer { tempSplitComplexRealPtr in
tempSplitComplexImag.withUnsafeMutableBufferPointer { tempSplitComplexImagPtr in
var tempSplitComplex = DSPDoubleSplitComplex(realp: tempSplitComplexRealPtr.baseAddress!,
imagp: tempSplitComplexImagPtr.baseAddress!)

// ----------------------------------------------------------------
// Bandpass Filtering
// ----------------------------------------------------------------

// Get the Frequencies for the current Framerate
let freqs = getFrequencies(N,fps: fps)
// Get a Bandpass Filter
let bandPassFilter = generateBandPassFilter(freqs)

// Multiply phase and magnitude with the bandpass filter
mag = mul(mag, y: bandPassFilter.0)
phase = mul(phase, y: bandPassFilter.0)

// Output Variables
let filteredSpectrum = mul(fullSpectrum, y: bandPassFilter.0)
var filteredPhase = phase

// ----------------------------------------------------------------
// Determine Maximum Frequency
// ----------------------------------------------------------------
let maxFrequencyResult = max(filteredSpectrum)
let maxFrequency = freqs[maxFrequencyResult.1]
let maxPhase = filteredPhase[maxFrequencyResult.1]

print("Amplitude: \(maxFrequencyResult.0)")
print("Frequency: \(maxFrequency)")
print("Phase: \(maxPhase + .pi / 2)")

// ----------------------------------------------------------------
// Convert from polar coordinates back to rectangular coordinates.
// ----------------------------------------------------------------

tempSplitComplex = DSPDoubleSplitComplex(realp: &mag, imagp: &phase)

var complexAsValue : UnsafeMutablePointer<Double>? = nil

tempComplex.withUnsafeMutableBytes {
complexAsValue = $0.baseAddress?.bindMemory(to: Double.self, capacity: values.count)
}

vDSP_ztocD(&tempSplitComplex, 1, &tempComplex, 2, N2);
vDSP_rectD(complexAsValue!, 2, complexAsValue!, 2, N2);
vDSP_ctozD(&tempComplex, 2, &tempSplitComplex, 1, N2);

// ----------------------------------------------------------------
// Do Inverse FFT
// ----------------------------------------------------------------

// Create result
var result : [Double] = [Double](repeating: 0.0, count: N)
var resultAsComplex : UnsafeMutablePointer<DSPDoubleComplex>? = nil

result.withUnsafeMutableBytes {
resultAsComplex = $0.baseAddress?.bindMemory(to: DSPDoubleComplex.self, capacity: values.count)
// ----------------------------------------------------------------
// Forward FFT
// ----------------------------------------------------------------

var valuesAsComplex : UnsafeMutablePointer<DSPDoubleComplex>? = nil

values.withUnsafeMutableBytes {
valuesAsComplex = $0.baseAddress?.bindMemory(to: DSPDoubleComplex.self, capacity: values1.count)
}

// Scramble-pack the real data into complex buffer in just the way that's
// required by the real-to-complex FFT function that follows.
vDSP_ctozD(valuesAsComplex!, 2, &tempSplitComplex, 1, N2);

// Do real->complex forward FFT
vDSP_fft_zripD(fftSetup, &tempSplitComplex, 1, LOG_N, FFTDirection(FFT_FORWARD));

// ----------------------------------------------------------------
// Get the Frequency Spectrum
// ----------------------------------------------------------------

var fftMagnitudes = [Double](repeating: 0.0, count: N/2)
vDSP_zvmagsD(&tempSplitComplex, 1, &fftMagnitudes, 1, N2);

// vDSP_zvmagsD returns squares of the FFT magnitudes, so take the root here
let roots = sqrt(fftMagnitudes)

// Normalize the Amplitudes
var fullSpectrum = [Double](repeating: 0.0, count: N/2)
vDSP_vsmulD(roots, vDSP_Stride(1), [1.0 / Double(N)], &fullSpectrum, 1, N2)

// ----------------------------------------------------------------
// Convert from complex/rectangular (real, imaginary) coordinates
// to polar (magnitude and phase) coordinates.
// ----------------------------------------------------------------

vDSP_zvabsD(&tempSplitComplex, 1, &mag, 1, N2);

// Beware: Outputted phase here between -PI and +PI
// https://developer.apple.com/library/prerelease/ios/documentation/Accelerate/Reference/vDSPRef/index.html#//apple_ref/c/func/vDSP_zvphasD
vDSP_zvphasD(&tempSplitComplex, 1, &phase, 1, N2);

// ----------------------------------------------------------------
// Bandpass Filtering
// ----------------------------------------------------------------

// Get the Frequencies for the current Framerate
let freqs = getFrequencies(N,fps: fps)
// Get a Bandpass Filter
let bandPassFilter = generateBandPassFilter(freqs)

// Multiply phase and magnitude with the bandpass filter
mag = mul(mag, y: bandPassFilter.0)
phase = mul(phase, y: bandPassFilter.0)

// Output Variables
let filteredSpectrum = mul(fullSpectrum, y: bandPassFilter.0)
let filteredPhase = phase

// ----------------------------------------------------------------
// Determine Maximum Frequency
// ----------------------------------------------------------------
let maxFrequencyResult = max(filteredSpectrum)
let maxFrequency = freqs[maxFrequencyResult.1]
let maxPhase = filteredPhase[maxFrequencyResult.1]

print("Amplitude: \(maxFrequencyResult.0)")
print("Frequency: \(maxFrequency)")
print("Phase: \(maxPhase + .pi / 2)")
}
}

// Do complex->real inverse FFT.
vDSP_fft_zripD(fftSetup, &tempSplitComplex, 1, LOG_N, FFTDirection(FFT_INVERSE));

// This leaves result in packed format. Here we unpack it into a real vector.
vDSP_ztocD(&tempSplitComplex, 1, resultAsComplex!, 2, N2);

// Neither the forward nor inverse FFT does any scaling. Here we compensate for that.
var scale : Double = 0.5/Double(N);
var copyOfResult = result;
vDSP_vsmulD(&result, 1, &scale, &copyOfResult, 1, vDSP_Length(N));
result = copyOfResult

// Print Result
for k in 0 ..< N {
print("\(k) \(values[k]) \(result[k])")
mag.withUnsafeMutableBufferPointer { magPtr in
phase.withUnsafeMutableBufferPointer { phasePtr in
// ----------------------------------------------------------------
// Convert from polar coordinates back to rectangular coordinates.
// ----------------------------------------------------------------

var tempSplitComplex = DSPDoubleSplitComplex(realp: magPtr.baseAddress!,
imagp: phasePtr.baseAddress!)

var complexAsValue : UnsafeMutablePointer<Double>? = nil

tempComplex.withUnsafeMutableBytes {
complexAsValue = $0.baseAddress?.bindMemory(to: Double.self, capacity: values.count)
}

vDSP_ztocD(&tempSplitComplex, 1, &tempComplex, 2, N2);
vDSP_rectD(complexAsValue!, 2, complexAsValue!, 2, N2);
vDSP_ctozD(&tempComplex, 2, &tempSplitComplex, 1, N2);

// ----------------------------------------------------------------
// Do Inverse FFT
// ----------------------------------------------------------------

// Create result
var result : [Double] = [Double](repeating: 0.0, count: N)
var resultAsComplex : UnsafeMutablePointer<DSPDoubleComplex>? = nil

result.withUnsafeMutableBytes {
resultAsComplex = $0.baseAddress?.bindMemory(to: DSPDoubleComplex.self, capacity: values.count)
}

// Do complex->real inverse FFT.
vDSP_fft_zripD(fftSetup, &tempSplitComplex, 1, LOG_N, FFTDirection(FFT_INVERSE));

// This leaves result in packed format. Here we unpack it into a real vector.
vDSP_ztocD(&tempSplitComplex, 1, resultAsComplex!, 2, N2);

// Neither the forward nor inverse FFT does any scaling. Here we compensate for that.
var scale : Double = 0.5/Double(N);
var copyOfResult = result;
vDSP_vsmulD(&result, 1, &scale, &copyOfResult, 1, vDSP_Length(N));
result = copyOfResult

// Print Result
for k in 0 ..< N {
print("\(k) \(values[k]) \(result[k])")
}
}
}
}

Expand Down