最新

.vscode/c_cpp_properties.json

@@ -0,0 +1,19 @@
+{
+    "configurations": [
+        {
+            "name": "Mac",
+            "includePath": [
+                "${workspaceFolder}/**"
+            ],
+            "defines": [],
+            "macFrameworkPath": [
+                "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks"
+            ],
+            "compilerPath": "/usr/bin/clang",
+            "cStandard": "c17",
+            "cppStandard": "c++17",
+            "intelliSenseMode": "macos-clang-arm64"
+        }
+    ],
+    "version": 4
+}

.vscode/settings.json

@@ -0,0 +1,8 @@
+{
+    "files.associations": {
+        "*.sdp": "xml",
+        "*.json": "jsonc",
+        "vector": "cpp",
+        "type_traits": "cpp"
+    }
+}

test/convert_image_to_webp.js

@@ -1111,16 +1111,79 @@ function dbg(...args) {
   var _emscripten_memcpy_js = (dest, src, num) => HEAPU8.copyWithin(dest, src, src + num);
 
   var getHeapMax = () =>
-      HEAPU8.length;
+      // Stay one Wasm page short of 4GB: while e.g. Chrome is able to allocate
+      // full 4GB Wasm memories, the size will wrap back to 0 bytes in Wasm side
+      // for any code that deals with heap sizes, which would require special
+      // casing all heap size related code to treat 0 specially.
+      2147483648;
   
-  var abortOnCannotGrowMemory = (requestedSize) => {
+  var growMemory = (size) => {
-      abort(`Cannot enlarge memory arrays to size ${requestedSize} bytes (OOM). Either (1) compile with -sINITIAL_MEMORY=X with X higher than the current value ${HEAP8.length}, (2) compile with -sALLOW_MEMORY_GROWTH which allows increasing the size at runtime, or (3) if you want malloc to return NULL (0) instead of this abort, compile with -sABORTING_MALLOC=0`);
+      var b = wasmMemory.buffer;
+      var pages = (size - b.byteLength + 65535) / 65536;
+      try {
+        // round size grow request up to wasm page size (fixed 64KB per spec)
+        wasmMemory.grow(pages); // .grow() takes a delta compared to the previous size
+        updateMemoryViews();
+        return 1 /*success*/;
+      } catch(e) {
+        err(`growMemory: Attempted to grow heap from ${b.byteLength} bytes to ${size} bytes, but got error: ${e}`);
+      }
+      // implicit 0 return to save code size (caller will cast "undefined" into 0
+      // anyhow)
     };
   var _emscripten_resize_heap = (requestedSize) => {
       var oldSize = HEAPU8.length;
       // With CAN_ADDRESS_2GB or MEMORY64, pointers are already unsigned.
       requestedSize >>>= 0;
-      abortOnCannotGrowMemory(requestedSize);
+      // With multithreaded builds, races can happen (another thread might increase the size
+      // in between), so return a failure, and let the caller retry.
+      assert(requestedSize > oldSize);
+  
+      // Memory resize rules:
+      // 1.  Always increase heap size to at least the requested size, rounded up
+      //     to next page multiple.
+      // 2a. If MEMORY_GROWTH_LINEAR_STEP == -1, excessively resize the heap
+      //     geometrically: increase the heap size according to
+      //     MEMORY_GROWTH_GEOMETRIC_STEP factor (default +20%), At most
+      //     overreserve by MEMORY_GROWTH_GEOMETRIC_CAP bytes (default 96MB).
+      // 2b. If MEMORY_GROWTH_LINEAR_STEP != -1, excessively resize the heap
+      //     linearly: increase the heap size by at least
+      //     MEMORY_GROWTH_LINEAR_STEP bytes.
+      // 3.  Max size for the heap is capped at 2048MB-WASM_PAGE_SIZE, or by
+      //     MAXIMUM_MEMORY, or by ASAN limit, depending on which is smallest
+      // 4.  If we were unable to allocate as much memory, it may be due to
+      //     over-eager decision to excessively reserve due to (3) above.
+      //     Hence if an allocation fails, cut down on the amount of excess
+      //     growth, in an attempt to succeed to perform a smaller allocation.
+  
+      // A limit is set for how much we can grow. We should not exceed that
+      // (the wasm binary specifies it, so if we tried, we'd fail anyhow).
+      var maxHeapSize = getHeapMax();
+      if (requestedSize > maxHeapSize) {
+        err(`Cannot enlarge memory, requested ${requestedSize} bytes, but the limit is ${maxHeapSize} bytes!`);
+        return false;
+      }
+  
+      var alignUp = (x, multiple) => x + (multiple - x % multiple) % multiple;
+  
+      // Loop through potential heap size increases. If we attempt a too eager
+      // reservation that fails, cut down on the attempted size and reserve a
+      // smaller bump instead. (max 3 times, chosen somewhat arbitrarily)
+      for (var cutDown = 1; cutDown <= 4; cutDown *= 2) {
+        var overGrownHeapSize = oldSize * (1 + 0.2 / cutDown); // ensure geometric growth
+        // but limit overreserving (default to capping at +96MB overgrowth at most)
+        overGrownHeapSize = Math.min(overGrownHeapSize, requestedSize + 100663296 );
+  
+        var newSize = Math.min(maxHeapSize, alignUp(Math.max(requestedSize, overGrownHeapSize), 65536));
+  
+        var replacement = growMemory(newSize);
+        if (replacement) {
+  
+          return true;
+        }
+      }
+      err(`Failed to grow the heap from ${oldSize} bytes to ${newSize} bytes, not enough memory!`);
+      return false;
     };
 
   var SYSCALLS = {
@@ -1406,7 +1469,6 @@ var missingLibrarySymbols = [
   'convertU32PairToI53',
   'zeroMemory',
   'exitJS',
-  'growMemory',
   'isLeapYear',
   'ydayFromDate',
   'arraySum',
@@ -1601,7 +1663,7 @@ var unexportedSymbols = [
   'convertI32PairToI53Checked',
   'ptrToString',
   'getHeapMax',
-  'abortOnCannotGrowMemory',
+  'growMemory',
   'ENV',
   'MONTH_DAYS_REGULAR',
   'MONTH_DAYS_LEAP',

test/index.html

@@ -45,7 +45,7 @@
         return btoa(binary);  // 使用 JavaScript 的 btoa() 函数
     }
 
-    var fileurl = './image.png'
+    var fileurl = './image.bin'
     // 初始化 WebAssembly 模块
     var Module = {
         onRuntimeInitialized: function () {

testCOut/main.cpp

@@ -0,0 +1,79 @@
+
+
+#include "./signalsmith-stretch.h"
+#include <vector>
+
+#include <emscripten.h>
+int main() {}
+
+using Sample = float;
+using Stretch = signalsmith::stretch::SignalsmithStretch<Sample>;
+Stretch stretch;
+
+// Allocates memory for buffers, and returns it
+std::vector<Sample> buffers;
+std::vector<Sample *> buffersIn, buffersOut;
+
+extern "C" {
+	Sample * EMSCRIPTEN_KEEPALIVE setBuffers(int channels, int length) {
+		buffers.resize(length*channels*2);
+		Sample *data = buffers.data();
+		buffersIn.resize(0);
+		buffersOut.resize(0);
+		for (int c = 0; c < channels; ++c) {
+			buffersIn.push_back(data + length*c);
+			buffersOut.push_back(data + length*(c + channels));
+		}
+		return data;
+	}
+
+	int EMSCRIPTEN_KEEPALIVE blockSamples() {
+		return stretch.blockSamples();
+	}
+	int EMSCRIPTEN_KEEPALIVE intervalSamples() {
+		return stretch.intervalSamples();
+	}
+	int EMSCRIPTEN_KEEPALIVE inputLatency() {
+		return stretch.inputLatency();
+	}
+	int EMSCRIPTEN_KEEPALIVE outputLatency() {
+		return stretch.outputLatency();
+	}
+	void EMSCRIPTEN_KEEPALIVE reset() {
+		stretch.reset();
+	}
+	void EMSCRIPTEN_KEEPALIVE presetDefault(int nChannels, Sample sampleRate) {
+		stretch.presetDefault(nChannels, sampleRate);
+	}
+	void EMSCRIPTEN_KEEPALIVE presetCheaper(int nChannels, Sample sampleRate) {
+		stretch.presetCheaper(nChannels, sampleRate);
+	}
+	void EMSCRIPTEN_KEEPALIVE configure(int nChannels, int blockSamples, int intervalSamples, bool splitComputation) {
+		stretch.configure(nChannels, blockSamples, intervalSamples, splitComputation);
+	}
+	void EMSCRIPTEN_KEEPALIVE setTransposeFactor(Sample multiplier, Sample tonalityLimit) {
+		stretch.setTransposeFactor(multiplier, tonalityLimit);
+	}
+	void EMSCRIPTEN_KEEPALIVE setTransposeSemitones(Sample semitones, Sample tonalityLimit) {
+		stretch.setTransposeSemitones(semitones, tonalityLimit);
+	}
+	void EMSCRIPTEN_KEEPALIVE setFormantFactor(Sample multiplier, bool compensate) {
+		stretch.setFormantFactor(multiplier, compensate);
+	}
+	void EMSCRIPTEN_KEEPALIVE setFormantSemitones(Sample semitones, bool compensate) {
+		stretch.setFormantSemitones(semitones, compensate);
+	}
+	void EMSCRIPTEN_KEEPALIVE setFormantBase(Sample freq) {
+		stretch.setFormantBase(freq);
+	}
+	// We can't do setFreqMap()
+	void EMSCRIPTEN_KEEPALIVE seek(int inputSamples, double playbackRate) {
+		stretch.seek(buffersIn, inputSamples, playbackRate);
+	}
+	void EMSCRIPTEN_KEEPALIVE process(int inputSamples, int outputSamples) {
+		stretch.process(buffersIn, inputSamples, buffersOut, outputSamples);
+	}
+	void EMSCRIPTEN_KEEPALIVE flush(int outputSamples) {
+		stretch.flush(buffersOut, outputSamples);
+	}
+}

testCOut/pre.js

@@ -0,0 +1,10 @@
+// Adapted from the Emscripten error message when initialising std::random_device
+var crypto = globalThis?.crypto || {
+	getRandomValues: array => {
+		// Cryptographically insecure, but fine for audio
+		for (var i = 0; i < array.length; i++) array[i] = (Math.random()*256)|0;
+	}
+};
+var performance = globalThis?.performance || {
+	now: _ => Date.now()
+};

testCOut/signalsmith-linear/stft.h

@@ -0,0 +1,631 @@
+#ifndef SIGNALSMITH_AUDIO_LINEAR_STFT_H
+#define SIGNALSMITH_AUDIO_LINEAR_STFT_H
+
+#include "./fft.h"
+
+namespace signalsmith { namespace linear {
+
+enum {
+	STFT_SPECTRUM_PACKED=0,
+	STFT_SPECTRUM_MODIFIED=1,
+	STFT_SPECTRUM_UNPACKED=2,
+};
+
+/// A self-normalising STFT, with variable position/window for output blocks
+template<typename Sample, bool splitComputation=false, int spectrumType=STFT_SPECTRUM_PACKED>
+struct DynamicSTFT {
+	static constexpr bool modified = (spectrumType == STFT_SPECTRUM_MODIFIED);
+	static constexpr bool unpacked = (spectrumType == STFT_SPECTRUM_UNPACKED);
+	RealFFT<Sample, splitComputation, modified> fft;
+
+	using Complex = std::complex<Sample>;
+
+	enum class WindowShape {ignore, acg, kaiser};
+	static constexpr WindowShape acg = WindowShape::acg;
+	static constexpr WindowShape kaiser = WindowShape::kaiser;
+
+	void configure(size_t inChannels, size_t outChannels, size_t blockSamples, size_t extraInputHistory=0, size_t intervalSamples=0, Sample asymmetry=0) {
+		_analysisChannels = inChannels;
+		_synthesisChannels = outChannels;
+		_blockSamples = blockSamples;
+		_fftSamples = fft.fastSizeAbove((blockSamples + 1)/2)*2;
+		fft.resize(_fftSamples);
+		_fftBins = _fftSamples/2 + (spectrumType == STFT_SPECTRUM_UNPACKED);
+		
+		_inputLengthSamples = _blockSamples + extraInputHistory;
+		input.buffer.resize(_inputLengthSamples*_analysisChannels);
+
+		output.buffer.resize(_blockSamples*_synthesisChannels);
+		output.windowProducts.resize(_blockSamples);
+		spectrumBuffer.resize(_fftBins*std::max(_analysisChannels, _synthesisChannels));
+		timeBuffer.resize(_fftSamples);
+
+		_analysisWindow.resize(_blockSamples);
+		_synthesisWindow.resize(_blockSamples);
+		setInterval(intervalSamples ? intervalSamples : blockSamples/4, acg, asymmetry);
+
+		reset();
+	}
+	
+	size_t blockSamples() const {
+		return _blockSamples;
+	}
+	size_t fftSamples() const {
+		return _fftSamples;
+	}
+	size_t defaultInterval() const {
+		return _defaultInterval;
+	}
+	size_t bands() const {
+		return _fftBins;
+	}
+	size_t analysisLatency() const {
+		return _blockSamples - _analysisOffset;
+	}
+	size_t synthesisLatency() const {
+		return _synthesisOffset;
+	}
+	size_t latency() const {
+		return synthesisLatency() + analysisLatency();
+	}
+	Sample binToFreq(Sample b) const {
+		return (modified ? b + Sample(0.5) : b)/_fftSamples;
+	}
+	Sample freqToBin(Sample f) const {
+		return modified ? f*_fftSamples - Sample(0.5) : f*_fftSamples;
+	}
+
+	void reset(Sample productWeight=1) {
+		input.pos = _blockSamples;
+		output.pos = 0;
+		for (auto &v : input.buffer) v = 0;
+		for (auto &v : output.buffer) v = 0;
+		for (auto &v : spectrumBuffer) v = 0;
+		for (auto &v : output.windowProducts) v = 0;
+		addWindowProduct();
+		for (int i = int(_blockSamples) - int(_defaultInterval) - 1; i >= 0; --i) {
+			output.windowProducts[i] += output.windowProducts[i + _defaultInterval];
+		}
+		for (auto &v : output.windowProducts) v = v*productWeight + almostZero;
+		moveOutput(_defaultInterval); // ready for first block immediately
+	}
+
+	void writeInput(size_t channel, size_t offset, size_t length, const Sample *inputArray) {
+		Sample *buffer = input.buffer.data() + channel*_inputLengthSamples;
+
+		size_t offsetPos = (input.pos + offset)%_inputLengthSamples;
+		size_t inputWrapIndex = _inputLengthSamples - offsetPos;
+		size_t chunk1 = std::min(length, inputWrapIndex);
+		for (size_t i = 0; i < chunk1; ++i) {
+			size_t i2 = offsetPos + i;
+			buffer[i2] = inputArray[i];
+		}
+		for (size_t i = chunk1; i < length; ++i) {
+			size_t i2 = i + offsetPos -_inputLengthSamples;
+			buffer[i2] = inputArray[i];
+		}
+	}
+	void writeInput(size_t channel, size_t length, const Sample *inputArray) {
+		writeInput(channel, 0, length, inputArray);
+	}
+	void moveInput(size_t samples, bool clearInput=false) {
+		if (clearInput) {
+			size_t inputWrapIndex = _inputLengthSamples - input.pos;
+			size_t chunk1 = std::min(samples, inputWrapIndex);
+			for (size_t c = 0; c < _analysisChannels; ++c) {
+				Sample *buffer = input.buffer.data() + c*_inputLengthSamples;
+				for (size_t i = 0; i < chunk1; ++i) {
+					size_t i2 = input.pos + i;
+					buffer[i2] = 0;
+				}
+				for (size_t i = chunk1; i < samples; ++i) {
+					size_t i2 = i + input.pos - _inputLengthSamples;
+					buffer[i2] = 0;
+				}
+			}
+		}
+
+		input.pos = (input.pos + samples)%_inputLengthSamples;
+		_samplesSinceAnalysis += samples;
+	}
+	size_t samplesSinceAnalysis() const {
+		return _samplesSinceAnalysis;
+	}
+
+	/// When no more synthesis is expected, let output taper away to 0 based on windowing.  Otherwise, the output will be scaled as if there's just a very long block interval, which can exaggerate artefacts and numerical errors.  You still can't read more than `blockSamples()` into the future.
+	void finishOutput(Sample strength=1, size_t offset=0) {
+		Sample maxWindowProduct = 0;
+		
+		size_t chunk1 = std::max(offset, std::min(_blockSamples, _blockSamples - output.pos));
+		
+		for (size_t i = offset; i < chunk1; ++i) {
+			size_t i2 = output.pos + i;
+			Sample &wp = output.windowProducts[i2];
+			maxWindowProduct = std::max(wp, maxWindowProduct);
+			wp += (maxWindowProduct - wp)*strength;
+		}
+		for (size_t i = chunk1; i < _blockSamples; ++i) {
+			size_t i2 = i + output.pos - _blockSamples;
+			Sample &wp = output.windowProducts[i2];
+			maxWindowProduct = std::max(wp, maxWindowProduct);
+			wp += (maxWindowProduct - wp)*strength;
+		}
+	}
+
+	void readOutput(size_t channel, size_t offset, size_t length, Sample *outputArray) {
+		Sample *buffer = output.buffer.data() + channel*_blockSamples;
+		size_t offsetPos = (output.pos + offset)%_blockSamples;
+		size_t outputWrapIndex = _blockSamples - offsetPos;
+		size_t chunk1 = std::min(length, outputWrapIndex);
+		for (size_t i = 0; i < chunk1; ++i) {
+			size_t i2 = offsetPos + i;
+			outputArray[i] = buffer[i2]/output.windowProducts[i2];
+		}
+		for (size_t i = chunk1; i < length; ++i) {
+			size_t i2 = i + offsetPos - _blockSamples;
+			outputArray[i] = buffer[i2]/output.windowProducts[i2];
+		}
+	}
+	void readOutput(size_t channel, size_t length, Sample *outputArray) {
+		return readOutput(channel, 0, length, outputArray);
+	}
+	void addOutput(size_t channel, size_t offset, size_t length, const Sample *newOutputArray) {
+		length = std::min(_blockSamples, length);
+		Sample *buffer = output.buffer.data() + channel*_blockSamples;
+		size_t offsetPos = (output.pos + offset)%_blockSamples;
+		size_t outputWrapIndex = _blockSamples - offsetPos;
+		size_t chunk1 = std::min(length, outputWrapIndex);
+		for (size_t i = 0; i < chunk1; ++i) {
+			size_t i2 = offsetPos + i;
+			buffer[i2] += newOutputArray[i]*output.windowProducts[i2];
+		}
+		for (size_t i = chunk1; i < length; ++i) {
+			size_t i2 = i + offsetPos - _blockSamples;
+			buffer[i2] += newOutputArray[i]*output.windowProducts[i2];
+		}
+	}
+	void addOutput(size_t channel, size_t length, const Sample *newOutputArray) {
+		return addOutput(channel, 0, length, newOutputArray);
+	}
+	void replaceOutput(size_t channel, size_t offset, size_t length, const Sample *newOutputArray) {
+		length = std::min(_blockSamples, length);
+		Sample *buffer = output.buffer.data() + channel*_blockSamples;
+		size_t offsetPos = (output.pos + offset)%_blockSamples;
+		size_t outputWrapIndex = _blockSamples - offsetPos;
+		size_t chunk1 = std::min(length, outputWrapIndex);
+		for (size_t i = 0; i < chunk1; ++i) {
+			size_t i2 = offsetPos + i;
+			buffer[i2] = newOutputArray[i]*output.windowProducts[i2];
+		}
+		for (size_t i = chunk1; i < length; ++i) {
+			size_t i2 = i + offsetPos - _blockSamples;
+			buffer[i2] = newOutputArray[i]*output.windowProducts[i2];
+		}
+	}
+	void replaceOutput(size_t channel, size_t length, const Sample *newOutputArray) {
+		return replaceOutput(channel, 0, length, newOutputArray);
+	}
+	void moveOutput(size_t samples) {
+		if (samples == 1) { // avoid all the loops/chunks if we can
+			for (size_t c = 0; c < _synthesisChannels; ++c) {
+				output.buffer[output.pos + c*_blockSamples] = 0;
+			}
+			output.windowProducts[output.pos] = almostZero;
+			if (++output.pos >= _blockSamples) output.pos = 0;
+			return;
+		}
+		// Zero the output buffer as we cross it
+		size_t outputWrapIndex = _blockSamples - output.pos;
+		size_t chunk1 = std::min(samples, outputWrapIndex);
+		for (size_t c = 0; c < _synthesisChannels; ++c) {
+			Sample *buffer = output.buffer.data() + c*_blockSamples;
+			for (size_t i = 0; i < chunk1; ++i) {
+				size_t i2 = output.pos + i;
+				buffer[i2] = 0;
+			}
+			for (size_t i = chunk1; i < samples; ++i) {
+				size_t i2 = i + output.pos - _blockSamples;
+				buffer[i2] = 0;
+			}
+		}
+		for (size_t i = 0; i < chunk1; ++i) {
+			size_t i2 = output.pos + i;
+			output.windowProducts[i2] = almostZero;
+		}
+		for (size_t i = chunk1; i < samples; ++i) {
+			size_t i2 = i + output.pos - _blockSamples;
+			output.windowProducts[i2] = almostZero;
+		}
+		output.pos = (output.pos + samples)%_blockSamples;
+		_samplesSinceSynthesis += samples;
+	}
+	size_t samplesSinceSynthesis() const {
+		return _samplesSinceSynthesis;
+	}
+	
+	Complex * spectrum(size_t channel) {
+		return spectrumBuffer.data() + channel*_fftBins;
+	}
+	const Complex * spectrum(size_t channel) const {
+		return spectrumBuffer.data() + channel*_fftBins;
+	}
+
+	Sample * analysisWindow() {
+		return _analysisWindow.data();
+	}
+	const Sample * analysisWindow() const {
+		return _analysisWindow.data();
+	}
+	// Sets the centre index of the window
+	void analysisOffset(size_t offset) {
+		_analysisOffset = offset;
+	}
+	size_t analysisOffset() const {
+		return _analysisOffset;
+	}
+	Sample * synthesisWindow() {
+		return _synthesisWindow.data();
+	}
+	const Sample * synthesisWindow() const {
+		return _synthesisWindow.data();
+	}
+	// Sets the centre index of the window
+	void synthesisOffset(size_t offset) {
+		_synthesisOffset = offset;
+	}
+	size_t synthesisOffset() const {
+		return _synthesisOffset;
+	}
+	
+	void setInterval(size_t defaultInterval, WindowShape windowShape=WindowShape::ignore, Sample asymmetry=0) {
+		_defaultInterval = defaultInterval;
+		if (windowShape == WindowShape::ignore) return;
+
+		if (windowShape == acg) {
+			auto window = ApproximateConfinedGaussian::withBandwidth(double(_blockSamples)/defaultInterval);
+			window.fill(_synthesisWindow, _blockSamples, asymmetry, false);
+		} else if (windowShape == kaiser) {
+			auto window = Kaiser::withBandwidth(double(_blockSamples)/defaultInterval, true);
+			window.fill(_synthesisWindow,  _blockSamples, asymmetry, true);
+		}
+
+		_analysisOffset = _synthesisOffset = _blockSamples/2;
+		if (_analysisChannels == 0) {
+			for (auto &v : _analysisWindow) v = 1;
+		} else if (asymmetry == 0) {
+			forcePerfectReconstruction(_synthesisWindow, _blockSamples, _defaultInterval);
+			for (size_t i = 0; i < _blockSamples; ++i) {
+				_analysisWindow[i] = _synthesisWindow[i];
+			}
+		} else {
+			for (size_t i = 0; i < _blockSamples; ++i) {
+				_analysisWindow[i] = _synthesisWindow[_blockSamples - 1 - i];
+			}
+		}
+		// Set offsets to peak's index
+		for (size_t i = 0; i < _blockSamples; ++i) {
+			if (_analysisWindow[i] > _analysisWindow[_analysisOffset]) _analysisOffset = i;
+			if (_synthesisWindow[i] > _synthesisWindow[_synthesisOffset]) _synthesisOffset = i;
+		}
+	}
+	
+	void analyse(size_t samplesInPast=0) {
+		for (size_t s = 0; s < analyseSteps(); ++s) {
+			analyseStep(s, samplesInPast);
+		}
+	}
+	size_t analyseSteps() const {
+		return splitComputation ? _analysisChannels*(fft.steps() + 1) : _analysisChannels;
+	}
+	void analyseStep(size_t step, std::size_t samplesInPast=0) {
+		size_t fftSteps = splitComputation ? fft.steps() : 0;
+		size_t channel = step/(fftSteps + 1);
+		step -= channel*(fftSteps + 1);
+		
+		if (step-- == 0) { // extra step at start of each channel: copy windowed input into buffer
+			size_t offsetPos = (_inputLengthSamples*2 + input.pos - _blockSamples - samplesInPast)%_inputLengthSamples;
+			size_t inputWrapIndex = _inputLengthSamples - offsetPos;
+			size_t chunk1 = std::min(_analysisOffset, inputWrapIndex);
+			size_t chunk2 = std::max(_analysisOffset, std::min(_blockSamples, inputWrapIndex));
+
+			_samplesSinceAnalysis = samplesInPast;
+			Sample *buffer = input.buffer.data() + channel*_inputLengthSamples;
+			for (size_t i = 0; i < chunk1; ++i) {
+				Sample w = modified ? -_analysisWindow[i] : _analysisWindow[i];
+				size_t ti = i + (_fftSamples - _analysisOffset);
+				size_t bi = offsetPos + i;
+				timeBuffer[ti] = buffer[bi]*w;
+			}
+			for (size_t i = chunk1; i < _analysisOffset; ++i) {
+				Sample w = modified ? -_analysisWindow[i] : _analysisWindow[i];
+				size_t ti = i + (_fftSamples - _analysisOffset);
+				size_t bi = i + offsetPos - _inputLengthSamples;
+				timeBuffer[ti] = buffer[bi]*w;
+			}
+			for (size_t i = _analysisOffset; i < chunk2; ++i) {
+				Sample w = _analysisWindow[i];
+				size_t ti = i - _analysisOffset;
+				size_t bi = offsetPos + i;
+				timeBuffer[ti] = buffer[bi]*w;
+			}
+			for (size_t i = chunk2; i < _blockSamples; ++i) {
+				Sample w = _analysisWindow[i];
+				size_t ti = i - _analysisOffset;
+				size_t bi = i + offsetPos - _inputLengthSamples;
+				timeBuffer[ti] = buffer[bi]*w;
+			}
+			for (size_t i = _blockSamples - _analysisOffset; i < _fftSamples - _analysisOffset; ++i) {
+				timeBuffer[i] = 0;
+			}
+			if (splitComputation) return;
+		}
+		auto *spectrumPtr = spectrum(channel);
+		if (splitComputation) {
+			fft.fft(step, timeBuffer.data(), spectrumPtr);
+			if (unpacked && step == fft.steps() - 1) {
+				spectrumPtr[_fftBins - 1] = spectrumPtr[0].imag();
+				spectrumPtr[0].imag(0);
+			}
+		} else {
+			fft.fft(timeBuffer.data(), spectrum(channel));
+			if (unpacked) {
+				spectrumPtr[_fftBins - 1] = spectrumPtr[0].imag();
+				spectrumPtr[0].imag(0);
+			}
+		}
+	}
+
+	void synthesise() {
+		for (size_t s = 0; s < synthesiseSteps(); ++s) {
+			synthesiseStep(s);
+		}
+	}
+	size_t synthesiseSteps() const {
+		return splitComputation ? (_synthesisChannels*(fft.steps() + 1) + 1) : _synthesisChannels;
+	}
+	void synthesiseStep(size_t step) {
+		if (step == 0) { // Extra first step which adds in the effective gain for a pure analysis-synthesis cycle
+			addWindowProduct();
+			if (splitComputation) return;
+		}
+		if (splitComputation) --step;
+
+		size_t fftSteps = splitComputation ? fft.steps() : 0;
+		size_t channel = step/(fftSteps + 1);
+		step -= channel*(fftSteps + 1);
+
+		auto *spectrumPtr = spectrum(channel);
+		if (unpacked && step == 0) { // re-pack
+			spectrumPtr[0].imag(spectrumPtr[_fftBins - 1].real());
+		}
+
+		if (splitComputation) {
+			if (step < fftSteps) {
+				fft.ifft(step, spectrumPtr, timeBuffer.data());
+				return;
+			}
+		} else {
+			fft.ifft(spectrumPtr, timeBuffer.data());
+		}
+		
+		// extra step after each channel's FFT
+		Sample *buffer = output.buffer.data() + channel*_blockSamples;
+		size_t outputWrapIndex = _blockSamples - output.pos;
+		size_t chunk1 = std::min(_synthesisOffset, outputWrapIndex);
+		size_t chunk2 = std::min(_blockSamples, std::max(_synthesisOffset, outputWrapIndex));
+		
+		for (size_t i = 0; i < chunk1; ++i) {
+			Sample w = modified ? -_synthesisWindow[i] : _synthesisWindow[i];
+			size_t ti = i + (_fftSamples - _synthesisOffset);
+			size_t bi = output.pos + i;
+			buffer[bi] += timeBuffer[ti]*w;
+		}
+		for (size_t i = chunk1; i < _synthesisOffset; ++i) {
+			Sample w = modified ? -_synthesisWindow[i] : _synthesisWindow[i];
+			size_t ti = i + (_fftSamples - _synthesisOffset);
+			size_t bi = i + output.pos - _blockSamples;
+			buffer[bi] += timeBuffer[ti]*w;
+		}
+		for (size_t i = _synthesisOffset; i < chunk2; ++i) {
+			Sample w = _synthesisWindow[i];
+			size_t ti = i - _synthesisOffset;
+			size_t bi = output.pos + i;
+			buffer[bi] += timeBuffer[ti]*w;
+		}
+		for (size_t i = chunk2; i < _blockSamples; ++i) {
+			Sample w = _synthesisWindow[i];
+			size_t ti = i - _synthesisOffset;
+			size_t bi = i + output.pos - _blockSamples;
+			buffer[bi] += timeBuffer[ti]*w;
+		}
+	}
+
+#define COMPAT_SPELLING(name, alt) \
+	template<class ...Args> \
+	void alt(Args &&...args) { \
+		name(std::forward<Args>(args)...); \
+	}
+	COMPAT_SPELLING(analyse, analyze);
+	COMPAT_SPELLING(analyseStep, analyseStep);
+	COMPAT_SPELLING(analyseSteps, analyzeSteps);
+	COMPAT_SPELLING(synthesise, synthesize);
+	COMPAT_SPELLING(synthesiseStep, synthesizeStep);
+	COMPAT_SPELLING(synthesiseSteps, synthesizeSteps);
+
+	/// Input (only available so we can save/restore the input state)
+	struct Input {
+		void swap(Input &other) {
+			std::swap(pos, other.pos);
+			std::swap(buffer, other.buffer);
+		}
+		
+		Input & operator=(const Input &other) {
+			pos = other.pos;
+			buffer.assign(other.buffer.begin(), other.buffer.end());
+			return *this;
+		}
+	private:
+		friend struct DynamicSTFT;
+		size_t pos = 0;
+		std::vector<Sample> buffer;
+	};
+	Input input;
+	
+	/// Output (only available so we can save/restore the output state)
+	struct Output {
+		void swap(Output &other) {
+			std::swap(pos, other.pos);
+			std::swap(buffer, other.buffer);
+			std::swap(windowProducts, other.windowProducts);
+		}
+
+		Output & operator=(const Output &other) {
+			pos = other.pos;
+			buffer.assign(other.buffer.begin(), other.buffer.end());
+			windowProducts.assign(other.windowProducts.begin(), other.windowProducts.end());
+			return *this;
+		}
+	private:
+		friend struct DynamicSTFT;
+		size_t pos = 0;
+		std::vector<Sample> buffer;
+		std::vector<Sample> windowProducts;
+	};
+	Output output;
+
+private:
+	static constexpr Sample almostZero = 1e-30;
+
+	size_t _analysisChannels, _synthesisChannels, _inputLengthSamples, _blockSamples, _fftSamples, _fftBins;
+	size_t _defaultInterval = 0;
+
+	std::vector<Sample> _analysisWindow, _synthesisWindow;
+	size_t _analysisOffset = 0, _synthesisOffset = 0;
+
+	std::vector<Complex> spectrumBuffer;
+	std::vector<Sample> timeBuffer;
+
+	size_t _samplesSinceSynthesis = 0, _samplesSinceAnalysis = 0;
+	
+	void addWindowProduct() {
+		_samplesSinceSynthesis = 0;
+
+		int windowShift = int(_synthesisOffset) - int(_analysisOffset);
+		size_t wMin = std::max<ptrdiff_t>(0, windowShift);
+		size_t wMax = std::min<ptrdiff_t>(_blockSamples, int(_blockSamples) + windowShift);
+
+		Sample *windowProduct = output.windowProducts.data();
+		size_t outputWrapIndex = _blockSamples - output.pos;
+		size_t chunk1 = std::min<size_t>(wMax, std::max<size_t>(wMin, outputWrapIndex));
+		for (size_t i = wMin; i < chunk1; ++i) {
+			Sample wa = _analysisWindow[i - windowShift];
+			Sample ws = _synthesisWindow[i];
+			size_t bi = output.pos + i;
+			windowProduct[bi] += wa*ws*_fftSamples;
+		}
+		for (size_t i = chunk1; i < wMax; ++i) {
+			Sample wa = _analysisWindow[i - windowShift];
+			Sample ws = _synthesisWindow[i];
+			size_t bi = i + output.pos - _blockSamples;
+			windowProduct[bi] += wa*ws*_fftSamples;
+		}
+	}
+	
+	// Copied from DSP library `windows.h`
+	class Kaiser {
+		inline static double bessel0(double x) {
+			const double significanceLimit = 1e-4;
+			double result = 0;
+			double term = 1;
+			double m = 0;
+			while (term > significanceLimit) {
+				result += term;
+				++m;
+				term *= (x*x)/(4*m*m);
+			}
+
+			return result;
+		}
+		double beta;
+		double invB0;
+		
+		static double heuristicBandwidth(double bandwidth) {
+			return bandwidth + 8/((bandwidth + 3)*(bandwidth + 3)) + 0.25*std::max(3 - bandwidth, 0.0);
+		}
+	public:
+		Kaiser(double beta) : beta(beta), invB0(1/bessel0(beta)) {}
+
+		static Kaiser withBandwidth(double bandwidth, bool heuristicOptimal=false) {
+			return Kaiser(bandwidthToBeta(bandwidth, heuristicOptimal));
+		}
+		static double bandwidthToBeta(double bandwidth, bool heuristicOptimal=false) {
+			if (heuristicOptimal) { // Heuristic based on numerical search
+				bandwidth = heuristicBandwidth(bandwidth);
+			}
+			bandwidth = std::max(bandwidth, 2.0);
+			double alpha = std::sqrt(bandwidth*bandwidth*0.25 - 1);
+			return alpha*M_PI;
+		}
+		
+		template<typename Data>
+		void fill(Data &&data, size_t size, double warp, bool isForSynthesis) const {
+			double invSize = 1.0/size;
+			size_t offsetI = (size&1) ? 1 : (isForSynthesis ? 0 : 2);
+			for (size_t i = 0; i < size; ++i) {
+				double r = (2*i + offsetI)*invSize - 1;
+				r = (r + warp)/(1 + r*warp);
+				double arg = std::sqrt(1 - r*r);
+				data[i] = bessel0(beta*arg)*invB0;
+			}
+		}
+	};
+
+	class ApproximateConfinedGaussian {
+		double gaussianFactor;
+		
+		double gaussian(double x) const {
+			return std::exp(-x*x*gaussianFactor);
+		}
+	public:
+		static double bandwidthToSigma(double bandwidth) {
+			return 0.3/std::sqrt(bandwidth);
+		}
+		static ApproximateConfinedGaussian withBandwidth(double bandwidth) {
+			return ApproximateConfinedGaussian(bandwidthToSigma(bandwidth));
+		}
+
+		ApproximateConfinedGaussian(double sigma) : gaussianFactor(0.0625/(sigma*sigma)) {}
+	
+		/// Fills an arbitrary container
+		template<typename Data>
+		void fill(Data &&data, size_t size, double warp, bool isForSynthesis) const {
+			double invSize = 1.0/size;
+			double offsetScale = gaussian(1)/(gaussian(3) + gaussian(-1));
+			double norm = 1/(gaussian(0) - 2*offsetScale*(gaussian(2)));
+			size_t offsetI = (size&1) ? 1 : (isForSynthesis ? 0 : 2);
+			for (size_t i = 0; i < size; ++i) {
+				double r = (2*i + offsetI)*invSize - 1;
+				r = (r + warp)/(1 + r*warp);
+				data[i] = norm*(gaussian(r) - offsetScale*(gaussian(r - 2) + gaussian(r + 2)));
+			}
+		}
+	};
+
+	template<typename Data>
+	void forcePerfectReconstruction(Data &&data, size_t windowLength, size_t interval) {
+		for (size_t i = 0; i < interval; ++i) {
+			double sum2 = 0;
+			for (size_t index = i; index < windowLength; index += interval) {
+				sum2 += data[index]*data[index];
+			}
+			double factor = 1/std::sqrt(sum2);
+			for (size_t index = i; index < windowLength; index += interval) {
+				data[index] *= factor;
+			}
+		}
+	}
+};
+
+}} // namespace
+
+#endif // include guard

testCOut/生成

@@ -0,0 +1,11 @@
+docker run --rm -v $(pwd):/src emscripten/emsdk \
+bash -c "em++ main.cpp  \
+-sEXPORT_NAME=testWasm -DEXPORT_NAME=testWasm \
+-I / \
+-std=c++11 -O3 -ffast-math -fno-exceptions -fno-rtti \
+--pre-js pre.js --closure 0 \
+-Wall -Wextra -Wfatal-errors -Wpedantic -pedantic-errors \
+-sSINGLE_FILE=1 -sMODULARIZE -sENVIRONMENT=web,worker,shell -sNO_EXIT_RUNTIME=1 \
+-sFILESYSTEM=0 -sEXPORTED_RUNTIME_METHODS=HEAP8,UTF8ToString \
+-sINITIAL_MEMORY=512kb -sALLOW_MEMORY_GROWTH=1 -sMEMORY_GROWTH_GEOMETRIC_STEP=0.5 -sABORTING_MALLOC=1 \
+-sSTRICT=1 -sDYNAMIC_EXECUTION=0"

utils(小程序兼容代码).js

@@ -0,0 +1,131 @@
+// wasm图片压缩工具类
+const wasmMgr = {
+  // 存储已加载的wasm模块
+  imageCompressModule: null,
+
+  // 获取图片压缩模块
+  getCompressImg() {
+    if (this.imageCompressModule) {
+      return Promise.resolve(this.imageCompressModule);
+    }
+    return new Promise((resolve, reject) => {
+      const wasmImports = {
+        __assert_fail: (condition, filename, line, func) => {
+          console.log(condition, filename, line, func);
+        },
+        emscripten_resize_heap: (size, old_size) => {
+          console.log(size, old_size);
+        },
+        fd_close: (fd) => {
+          console.log(fd);
+        },
+        fd_seek: (fd, offset, whence) => {
+          console.log(fd, offset, whence);
+        },
+        fd_write: (fd, buf, len, pos) => {
+          console.log(fd, buf, len, pos);
+        },
+        emscripten_memcpy_js: (dest, src, len) => {
+          this.imageCompressModule.HEAPU8.copyWithin(dest, src, src + len);
+        },
+      };
+
+      // 微信小程序环境
+      if (typeof WXWebAssembly !== "undefined") {
+        WXWebAssembly.instantiate(
+          "/convert_image_to_webp.wasm",
+          {
+            env: wasmImports,
+            wasi_snapshot_preview1: wasmImports,
+          }
+        ).then((result) => {
+          this.imageCompressModule = {
+            _convert_image_to_webp: result.instance.exports.convert_image_to_webp,
+            _malloc: result.instance.exports.malloc,
+            _free: result.instance.exports.free,
+          };
+          this.imageCompressModule.HEAPU8 = new Uint8Array(
+            result.instance.exports.memory.buffer
+          );
+          console.log("convert_image_to_webp加载成功");
+          resolve(this.imageCompressModule);
+        }).catch((err) => {
+          console.error("Failed to load wasm script", err);
+          reject(err);
+        });
+      } else {
+        // H5环境或其他环境
+        console.error("当前环境不支持WebAssembly");
+        reject(new Error("当前环境不支持WebAssembly"));
+      }
+    });
+  },
+
+  // 图片压缩函数
+  async compressImg(file, quality = 0.5, w, h, target_w, target_h) {
+    const compressImgHandler = (inputData, module, isOrgin = false) => {
+      const inputDataPtr = module._malloc(inputData.length);
+      module.HEAPU8.set(inputData, inputDataPtr);
+      const outputSizePtr = module._malloc(4);
+      const webpPtr = module._convert_image_to_webp(
+        inputDataPtr,
+        inputData.length,
+        w,
+        h,
+        target_w,
+        target_h,
+        80 * (quality > 1 ? 1 : quality),
+        outputSizePtr,
+        1,
+        isOrgin ? 1 : 0
+      );
+      const outputSize =
+        module.HEAPU8[outputSizePtr] |
+        (module.HEAPU8[outputSizePtr + 1] << 8) |
+        (module.HEAPU8[outputSizePtr + 2] << 16) |
+        (module.HEAPU8[outputSizePtr + 3] << 24);
+      const webpData = new Uint8Array(module.HEAPU8.buffer, webpPtr, outputSize);
+      module._free(webpPtr);
+      module._free(outputSizePtr);
+      module._free(inputDataPtr);
+      //如果只需要二进制原始数据，可以直接返回webpdata 减少base64转换
+      // return webpData
+      return 'data:image/webp;base64,' + this.arrayBufferToBase64(webpData);
+    };
+
+    try {
+      const module = await this.getCompressImg();
+      
+      if (file instanceof Uint8Array) {
+        return compressImgHandler(file, module, true);
+      } else {
+        return new Promise((resolve, reject) => {
+          wx.getFileSystemManager().readFile({
+            filePath: file,
+            success: res => {
+              resolve(compressImgHandler(new Uint8Array(res.data), module));
+            },
+            fail: e => {
+              console.error("读取文件失败", e);
+              reject(e);
+            },
+          });
+        });
+      }
+    } catch (error) {
+      console.error("图片压缩失败", error);
+      throw error;
+    }
+  },
+
+  // 将ArrayBuffer转换为Base64
+  arrayBufferToBase64(buffer) {
+
+    return wx.arrayBufferToBase64(buffer);
+
+  }
+};
+
+module.exports = {
+  wasmMgr
+};

生成

@@ -1,6 +1,6 @@
 # 调试模式
-docker run --rm -v $(pwd):/src emscripten/emsdk emcc convert_image_to_webp.cpp stb_image.c libwebp.a libsharpyuv.a libwebpdecoder.a libwebpdemux.a libwebpmux.a -o ./test/convert_image_to_webp.js -g -s WASM=1 -s INITIAL_MEMORY=34340864 -s EXPORTED_FUNCTIONS="['_free','_malloc','_convert_image_to_webp']" -s EXTRA_EXPORTED_RUNTIME_METHODS='["cwrap", "getValue"]' -gsource-map 
+docker run --rm -v $(pwd):/src emscripten/emsdk emcc convert_image_to_webp.cpp stb_image.c libwebp.a libsharpyuv.a libwebpdecoder.a libwebpdemux.a libwebpmux.a -o ./test/convert_image_to_webp.js -g -s WASM=1 -s INITIAL_MEMORY=20MB -s ALLOW_MEMORY_GROWTH=1  -s EXPORTED_FUNCTIONS="['_free','_malloc','_convert_image_to_webp']" -s EXTRA_EXPORTED_RUNTIME_METHODS='["cwrap", "getValue"]' -gsource-map 
 
 
 # 优化后的命令
-docker run --rm -v $(pwd):/src emscripten/emsdk emcc convert_image_to_webp.cpp stb_image.c libwebp.a libsharpyuv.a -o ./output/convert_image_to_webp.js -s WASM=1 -s NO_FILESYSTEM=1 -s INITIAL_MEMORY=34340864 -s ALLOW_MEMORY_GROWTH=1 -s MAXIMUM_MEMORY=268435456 -s EXPORTED_FUNCTIONS="['_free','_malloc','_convert_image_to_webp']" -s EXTRA_EXPORTED_RUNTIME_METHODS='["cwrap", "getValue"]' -O2
+docker run --rm -v $(pwd):/src emscripten/emsdk emcc convert_image_to_webp.cpp stb_image.c libwebp.a libsharpyuv.a -o ./output/convert_image_to_webp.js -s WASM=1 -s NO_FILESYSTEM=1 -s INITIAL_MEMORY=512MB -s EXPORTED_FUNCTIONS="['_free','_malloc','_convert_image_to_webp']" -s EXTRA_EXPORTED_RUNTIME_METHODS='["cwrap", "getValue"]' -O2