Reduce FFT memory slightly

cmd/Makefile

@@ -1,8 +1,11 @@
 all: out/stretch
 
-out/stretch: ../signalsmith-stretch.h main.cpp util/*.h
+out/stretch: ../signalsmith-stretch.h main.cpp util/*.h util/*.hxx ../dsp/*.h
 	mkdir -p out
-	g++ main.cpp -o out/stretch -std=c++11 -Ofast -g
+	g++ main.cpp -o out/stretch -std=c++11 -O3 -g
+
+examples: out/stretch
+	inputs/run-all.sh out/d1- out/stretch --semitones=-1
 
 clean:
 	rm -rf out

cmd/main.cpp

@@ -1,5 +1,11 @@
+#include "util/memory-tracker.hxx"
+
 #include <iostream>
 #define LOG_EXPR(expr) std::cout << #expr << " = " << (expr) << "\n";
+std::ostream& operator<<(std::ostream& output, const signalsmith::MemoryTracker& memory) {
+	output << "{.allocBytes=" << memory.allocBytes << ", .freeBytes=" << memory.freeBytes << ", .current=" << memory.currentBytes << "}";
+	return output;
+}
 
 #include <ctime>
 
@@ -7,8 +13,6 @@
 #include "util/simple-args.h"
 #include "util/wav.h"
 
-#include "util/memory-tracker.hxx"
-
 int main(int argc, char* argv[]) {
 	SimpleArgs args(argc, argv);
 	
@@ -24,7 +28,7 @@ int main(int argc, char* argv[]) {
 	Wav inWav;
 	if (!inWav.read(inputWav).warn()) args.errorExit("failed to read WAV");
 	size_t inputLength = inWav.samples.size()/inWav.channels;
-
+	
 	Wav prevWav;
 	prevWav.read(outputWav); // to verify it's the same output
 
@@ -62,7 +66,7 @@ int main(int argc, char* argv[]) {
 	stretch.process(inWav, inputLength, outWav, outputLength);
 
 	processMemory = processMemory.diff();
-	if (processMemory.allocBytes + processMemory.freeBytes > 0) {
+	if (processMemory) {
 		std::cout << "Processing (alloc/free/current):\t" << processMemory.allocBytes << "/" << processMemory.freeBytes << "/" << processMemory.currentBytes << "\n";
 		args.errorExit("allocated during process()");
 	}

cmd/util/memory-tracker.h

@@ -14,6 +14,11 @@ struct MemoryTracker {
 		MemoryTracker now;
 		return {now.allocBytes - allocBytes, now.freeBytes - freeBytes};
 	}
+
+	// Is a `.diff()` result non-zero
+	operator bool() const {
+		return allocBytes > 0 || freeBytes > 0;
+	}
 private:
 	MemoryTracker(size_t allocBytes, size_t freeBytes) : allocBytes(allocBytes), freeBytes(freeBytes), currentBytes(allocBytes - freeBytes) {}
 };

dsp/fft.h

@@ -164,8 +164,10 @@ namespace signalsmith { namespace fft {
 			plan.resize(0);
 			twiddleVector.resize(0);
 			addPlanSteps(0, 0, _size, 1);
+			twiddleVector.shrink_to_fit();
 			
 			permutation.resize(0);
+			permutation.reserve(_size);
 			permutation.push_back(PermutationPair{0, 0});
 			size_t indexLow = 0, indexHigh = factors.size();
 			size_t inputStepLow = _size, outputStepLow = 1;
@@ -524,7 +526,8 @@ namespace signalsmith { namespace fft {
 				}
 			}
 			
-			return complexFft.setSize(size/2);
+			size_t result = complexFft.setSize(size/2);
+			return result*2;
 		}
 		size_t setFastSizeAbove(size_t size) {
 			return setSize(fastSizeAbove(size));

dsp/spectral.h

@@ -170,6 +170,7 @@ namespace spectral {
 	*/
 	template<typename Sample>
 	class STFT : public signalsmith::delay::MultiBuffer<Sample> {
+
 		using Super = signalsmith::delay::MultiBuffer<Sample>;
 		using Complex = std::complex<Sample>;
 
@@ -215,7 +216,7 @@ namespace spectral {
 				+ historyLength);
 
 			int fftSize = fft.fastSizeAbove(windowSize + zeroPadding);
-			
+
 			this->channels = newChannels;
 			_windowSize = windowSize;
 			this->_fftSize = fftSize;