// This is the core JavaScript for the Spectrogram Editor. // It handles file loading (.spec), visualization, tool interaction, and saving. // --- Global Variables --- let currentSpecData = null; // Stores the currently displayed/edited spectrogram data let originalSpecData = null; // Stores the pristine, initially loaded spectrogram data let undoStack = []; let redoStack = []; const MAX_HISTORY_SIZE = 50; let activeTool = null; // 'line', 'ellipse', 'noise', etc. let isDrawing = false; let startX, startY; // For tracking mouse down position let shapes = []; // Array to store all drawn shapes (lines, ellipses, etc.) // Web Audio Context const audioContext = new (window.AudioContext || window.webkitAudioContext)(); // Audio Constants (should match C++ side) const SAMPLE_RATE = 32000; const MAX_FREQ = SAMPLE_RATE / 2; // Nyquist frequency const MIN_FREQ = 20; // Lower bound for log scale visualization const SDF_FALLOFF_FACTOR = 10.0; // Adjust this value to control the softness of SDF edges. // --- Button Element Declarations --- const specFileInput = document.getElementById('specFileInput'); const lineToolButton = document.getElementById('lineTool'); const ellipseToolButton = document.getElementById('ellipseTool'); const noiseToolButton = document.getElementById('noiseTool'); const undoButton = document.getElementById('undoButton'); const redoButton = document.getElementById('redoButton'); const listenOriginalButton = document.getElementById('listenOriginalButton'); const listenGeneratedButton = document.getElementById('listenGeneratedButton'); // --- Event Listeners --- specFileInput.addEventListener('change', handleFileSelect); lineToolButton.addEventListener('click', () => { activeTool = 'line'; console.log('Line tool selected'); }); ellipseToolButton.addEventListener('click', () => { activeTool = 'ellipse'; console.log('Ellipse tool selected'); }); noiseToolButton.addEventListener('click', () => { activeTool = 'noise'; console.log('Noise tool selected'); }); undoButton.addEventListener('click', handleUndo); redoButton.addEventListener('click', handleRedo); listenOriginalButton.addEventListener('click', () => { if (originalSpecData) { playSpectrogramData(originalSpecData); } else { alert("No original SPEC data loaded."); } }); listenGeneratedButton.addEventListener('click', () => { if (currentSpecData) { redrawCanvas(); // Ensure currentSpecData reflects all shapes before playing playSpectrogramData(currentSpecData); } else { alert("No generated SPEC data to play."); } }); // --- Utility to map canvas coords to spectrogram bins/frames (LOG SCALE) --- // Maps a linear frequency bin index to its corresponding frequency in Hz function binIndexToFreq(binIndex) { return (binIndex / (dctSize / 2)) * MAX_FREQ; } // Maps a frequency in Hz to its corresponding linear bin index function freqToBinIndex(freq) { return Math.floor((freq / MAX_FREQ) * (dctSize / 2)); } // Maps a frequency (Hz) to its corresponding log-scaled bin index function freqToBinIndexLog(freq) { if (freq < MIN_FREQ) freq = MIN_FREQ; // Clamp minimum frequency const logMin = Math.log(MIN_FREQ); const logMax = Math.log(MAX_FREQ); const logFreq = Math.log(freq); const normalizedLog = (logFreq - logMin) / (logMax - logMin); return Math.floor(normalizedLog * dctSize); } // Maps a log-scaled bin index to its corresponding frequency in Hz function binIndexToFreqLog(binIndex) { const normalizedLog = binIndex / dctSize; const logMin = Math.log(MIN_FREQ); const logMax = Math.log(MAX_FREQ); const logFreq = normalizedLog * (logMax - logMin) + logMin; return Math.exp(logFreq); } // Converts a frequency (Hz) to a Y-coordinate on the canvas (log scale) function freqToCanvasYLog(freq, canvasHeight) { if (freq < MIN_FREQ) freq = MIN_FREQ; // Clamp minimum frequency const logMin = Math.log(MIN_FREQ); const logMax = Math.log(MAX_FREQ); const logFreq = Math.log(freq); const normalizedLog = (logFreq - logMin) / (logMax - logMin); return canvasHeight * (1 - normalizedLog); // Y-axis is inverted } // Converts a Y-coordinate on the canvas to a frequency (Hz) (log scale) function canvasYToFreqLog(canvasY, canvasHeight) { const normalizedLog = 1 - (canvasY / canvasHeight); const logMin = Math.log(MIN_FREQ); const logMax = Math.log(MAX_FREQ); const logFreq = normalizedLog * (logMax - logMin) + logMin; return Math.exp(logFreq); } // Converts canvas Y-coordinate to log-scaled bin index function canvasYToBinIndexLog(canvasY, specData) { const freq = canvasYToFreqLog(canvasY, canvas.height); return freqToBinIndex(freq); // Use linear bin index from calculated log freq } // Converts log-scaled bin index to canvas Y-coordinate function binIndexToCanvasYLog(binIndex, specData) { const freq = binIndexToFreq(binIndex); return freqToCanvasYLog(freq, canvas.height); } // Helper to get frequency delta from canvas delta (for ellipse radius in freq) function canvasDeltaYToFreqDeltaLog(canvasDeltaY, canvasHeight) { // This is an approximation as delta in log scale is not linear // For small deltas around a center, it can be approximated const centerCanvasY = canvasHeight / 2; const freqAtCenter = canvasYToFreqLog(centerCanvasY, canvasHeight); const freqAtCenterPlusDelta = canvasYToFreqLog(centerCanvasY - canvasDeltaY, canvasHeight); return Math.abs(freqAtCenterPlusDelta - freqAtCenter); } // Initial setup for canvas size (can be updated on window resize) window.addEventListener('resize', () => { if (originalSpecData) { canvas.width = window.innerWidth * 0.7; canvas.height = 400; // Fixed height redrawCanvas(); } }); // Initial call to set button states updateUndoRedoButtons(); // --- File Handling Functions --- async function handleFileSelect(event) { const file = event.target.files[0]; if (!file) { return; } try { const buffer = await file.arrayBuffer(); const dataView = new DataView(buffer); // Parse SPEC header const header = { magic: String.fromCharCode(...new Uint8Array(buffer.slice(0, 4))), version: dataView.getInt32(4, true), dct_size: dataView.getInt32(8, true), num_frames: dataView.getInt32(12, true) }; if (header.magic !== "SPEC" || header.version !== 1) { console.error("Invalid SPEC file format."); alert("Invalid SPEC file format. Please load a valid .spec file."); return; } if (dctSize != header.dct_size) { alert("Invalid dctSize in SPEC file"); return; } const dataStart = 16; const numBytes = header.num_frames * header.dct_size * Float32Array.BYTES_PER_ELEMENT; const spectralDataFloat = new Float32Array(buffer, dataStart, header.num_frames * header.dct_size); originalSpecData = { header: header, data: new Float32Array(spectralDataFloat) }; // Store pristine copy currentSpecData = { header: header, data: new Float32Array(spectralDataFloat) }; // Editable copy shapes = []; // Clear shapes on new file load undoStack = []; // Clear undo history redoStack = []; // Clear redo history console.log("Loaded SPEC file:", header); redrawCanvas(); // Redraw with new data } catch (error) { console.error("Error loading SPEC file:", error); alert("Failed to load SPEC file. Check console for details."); } } // --- Spectrogram Visualization --- const canvas = document.getElementById('spectrogramCanvas'); const ctx = canvas.getContext('2d'); // Add canvas event listeners canvas.addEventListener('mousedown', handleMouseDown); canvas.addEventListener('mousemove', handleMouseMove); canvas.addEventListener('mouseup', handleMouseUp); canvas.addEventListener('mouseout', handleMouseUp); // Treat mouse out as mouse up // Function to get a color based on intensity (0 to 1) function getColorForIntensity(intensity) { // Example: Blue to white/yellow gradient const log_intensity = Math.log(1. + intensity) / Math.log(2.); const h = (1 - log_intensity) * 240; // Hue from blue (240) to red (0), inverse for intensity const s = 60.; // Saturation const l = log_intensity * 60 + 30; // Lightness from 30 to 90 return `hsl(${h}, ${s}%, ${l}%)`; } function drawSpectrogram(specData) { const width = canvas.width; const height = canvas.height; ctx.clearRect(0, 0, width, height); ctx.fillStyle = '#ffffff'; ctx.fillRect(0, 0, width, height); if (!specData || !specData.data || specData.header.num_frames === 0 || specData.data.length === 0) { console.warn("No spectrogram data or invalid header/data to draw."); return; } const numFrames = specData.header.num_frames; const frameWidth = width / numFrames; // Width of each time frame // Draw each frame's spectral data with log frequency scale for (let frameIndex = 0; frameIndex < numFrames; frameIndex++) { const frameDataStart = frameIndex * dctSize; const xPos = frameIndex * frameWidth; // To draw with log scale, we iterate over canvas y-coordinates // and map them back to frequency bins for (let y = 0; y < height; y++) { const binIndex = canvasYToBinIndexLog(y, specData); if (binIndex < 0 || binIndex >= dctSize) continue; // Out of bounds const value = specData.data[frameDataStart + binIndex]; const intensity = Math.min(1, Math.abs(value) / 1.0); // Assuming values are normalized to [-1, 1] ctx.fillStyle = getColorForIntensity(intensity); ctx.fillRect(xPos, height - y - 1, frameWidth, 1); // Draw a 1-pixel height line for each y } } // Draw active shapes on top (previews for current drawing tool) shapes.forEach(shape => { drawShape(shape); }); } function drawShape(shape) { // This draws the final, persistent shape. Preview is drawn in handleMouseMove. ctx.strokeStyle = shape.color || 'red'; ctx.lineWidth = shape.width || 2; switch (shape.type) { case 'line': ctx.beginPath(); ctx.moveTo(shape.x1, shape.y1); ctx.lineTo(shape.x2, shape.y2); ctx.stroke(); break; case 'ellipse': ctx.beginPath(); ctx.ellipse(shape.cx, shape.cy, shape.rx, shape.ry, 0, 0, 2 * Math.PI); ctx.stroke(); break; case 'noise_rect': // Noise is visualized as a rectangle ctx.fillStyle = 'rgba(0, 0, 255, 0.2)'; ctx.fillRect(shape.x, shape.y, shape.width, shape.height); ctx.strokeStyle = 'blue'; ctx.strokeRect(shape.x, shape.y, shape.width, shape.height); break; } } // --- Mouse Event Handlers --- function getMousePos(event) { const rect = canvas.getBoundingClientRect(); return { x: event.clientX - rect.left, y: event.clientY - rect.top }; } function handleMouseDown(event) { if (!activeTool || !currentSpecData) return; isDrawing = true; const pos = getMousePos(event); startX = pos.x; startY = pos.y; } function handleMouseMove(event) { if (!isDrawing || !activeTool) return; const pos = getMousePos(event); redrawCanvas(); // Clear and redraw persistent state ctx.strokeStyle = 'rgba(0, 0, 0, 0.5)'; // Preview color ctx.lineWidth = 1; ctx.setLineDash([5, 5]); // Dashed line for preview switch (activeTool) { case 'line': ctx.beginPath(); ctx.moveTo(startX, startY); ctx.lineTo(pos.x, pos.y); ctx.stroke(); break; case 'ellipse': // Draw preview ellipse based on start and current pos (bounding box) const rx = Math.abs(pos.x - startX) / 2; const ry = Math.abs(pos.y - startY) / 2; const cx = startX + (pos.x - startX) / 2; const cy = startY + (pos.y - startY) / 2; if (rx > 0 && ry > 0) { ctx.beginPath(); ctx.ellipse(cx, cy, rx, ry, 0, 0, 2 * Math.PI); ctx.stroke(); } break; case 'noise': // Draw preview rectangle for noise area const rectX = Math.min(startX, pos.x); const rectY = Math.min(startY, pos.y); const rectW = Math.abs(pos.x - startX); const rectH = Math.abs(pos.y - startY); ctx.strokeRect(rectX, rectY, rectW, rectH); break; } ctx.setLineDash([]); // Reset line dash // debug the mouse position by draw a white square ctx.fillStyle = '#fff'; ctx.fillRect(pos.x - 10, pos.y - 10, 20, 20); } function handleMouseUp(event) { if (!isDrawing || !activeTool || !currentSpecData) return; isDrawing = false; const endPos = getMousePos(event); let newShape = null; switch (activeTool) { case 'line': { const startCoords = canvasToSpectrogramCoords(startX, startY, currentSpecData); const endCoords = canvasToSpectrogramCoords(endPos.x, endPos.y, currentSpecData); newShape = { type: 'line', // Canvas coordinates for drawing visual representation (unchanged) x1: startX, y1: startY, x2: endPos.x, y2: endPos.y, // World coordinates for SDF calculations (frame and log-scaled frequency) frame1_world: startCoords.frame, freq1_world: binIndexToFreqLog(startCoords.bin), frame2_world: endCoords.frame, freq2_world: binIndexToFreqLog(endCoords.bin), amplitude: 0.5, // Default amplitude width: 2, // Visual width in canvas pixels, not directly used by SDF, but kept for drawing color: 'red', falloff: SDF_FALLOFF_FACTOR, // SDF falloff factor }; break; } case 'ellipse': { const rx = Math.abs(endPos.x - startX) / 2; const ry = Math.abs(endPos.y - startY) / 2; const cx = startX + (pos.x - startX) / 2; const cy = startY + (pos.y - startY) / 2; const centerCoords = canvasToSpectrogramCoords(cx, cy, currentSpecData); const halfWidthFrames = Math.floor((rx / canvas.width) * currentSpecData.header.num_frames); const startFreq = canvasYToFreqLog(startY, canvas.height); const endFreq = canvasYToFreqLog(endPos.y, canvas.height); const centerFreq = (startFreq + endFreq) / 2; const halfHeightFreq = Math.abs(startFreq - endFreq) / 2; newShape = { type: 'ellipse', // Canvas coordinates for drawing visual representation (unchanged) cx: cx, cy: cy, rx: rx, ry: ry, // World coordinates for SDF calculations center_frame_world: centerCoords.frame, center_freq_world: centerFreq, radius_frames_world: halfWidthFrames, radius_freq_world: halfHeightFreq, amplitude: 0.5, color: 'green', falloff: SDF_FALLOFF_FACTOR, }; break; } case 'noise': { const rectX = Math.min(startX, endPos.x); const rectY = Math.min(startY, endPos.y); const rectW = Math.abs(endPos.x - startX); const rectH = Math.abs(endPos.y - startY); const startCoords = canvasToSpectrogramCoords(rectX, rectY, currentSpecData); const endCoords = canvasToSpectrogramCoords(rectX + rectW, rectY + rectH, currentSpecData); const centerFrame = Math.floor((startCoords.frame + endCoords.frame) / 2); const centerFreq = (binIndexToFreqLog(startCoords.bin) + binIndexToFreqLog(endCoords.bin)) / 2; const halfExtentFrames = Math.floor(Math.abs(endCoords.frame - startCoords.frame) / 2); const halfExtentFreq = Math.abs(binIndexToFreqLog(endCoords.bin) - binIndexToFreqLog(startCoords.bin)) / 2; newShape = { type: 'noise_rect', // Canvas coordinates for drawing visual representation (unchanged) x: rectX, y: rectY, width: rectW, height: rectH, // World coordinates for SDF calculations center_frame_world: centerFrame, center_freq_world: centerFreq, half_extent_frames_world: halfExtentFrames, half_extent_freq_world: halfExtentFreq, amplitude: 0.3, // Default noise amplitude density: 0.5, // Default noise density color: 'blue', falloff: 0.0, // No falloff for pure noise inside rect }; break; } } if (newShape) { // Capture the state *before* applying the new shape for undo const previousDataSnapshot = new Float32Array(currentSpecData.data); // Copy of actual data const previousShapesSnapshot = shapes.map(s => ({ ...s })); // Deep copy shapes array applyShapeToSpectrogram(newShape, currentSpecData); // Modify currentSpecData directly shapes.push(newShape); addAction({ type: 'add_shape', shape: newShape, undo: () => { // To undo, restore previous shapes and previous data shapes = previousShapesSnapshot; currentSpecData.data = previousDataSnapshot; }, redo: () => { // To redo, add the shape back and apply it to current data shapes.push(newShape); applyShapeToSpectrogram(newShape, currentSpecData); } }); } redrawCanvas(); // Final redraw after action updateUndoRedoButtons(); } // --- Spectrogram Data Manipulation --- function applyShapeToSpectrogram(shape, targetSpecData) { if (!targetSpecData || !targetSpecData.data || targetSpecData.header.num_frames === 0) return; const numFrames = targetSpecData.header.num_frames; // Determine a bounding box for optimization (iterate only relevant cells) let minFrame = 0, maxFrame = numFrames - 1; let minBin = 0, maxBin = dctSize - 1; // Calculate tighter bounding boxes for each shape type switch (shape.type) { case 'line': minFrame = Math.min(shape.frame1_world, shape.frame2_world) - Math.ceil(shape.width / 2); maxFrame = Math.max(shape.frame1_world, shape.frame2_world) + Math.ceil(shape.width / 2); // For frequency, approximate by visual width or a fixed range if needed minBin = freqToBinIndex(Math.min(shape.freq1_world, shape.freq2_world)) - Math.ceil(shape.width / 2); maxBin = freqToBinIndex(Math.max(shape.freq1_world, shape.freq2_world)) + Math.ceil(shape.width / 2); break; case 'ellipse': minFrame = shape.center_frame_world - shape.radius_frames_world - 1; maxFrame = shape.center_frame_world + shape.radius_frames_world + 1; minBin = freqToBinIndex(shape.center_freq_world - shape.radius_freq_world) - 1; // Approx bin range from world freq maxBin = freqToBinIndex(shape.center_freq_world + shape.radius_freq_world) + 1; // Approx bin range from world freq break; case 'noise_rect': minFrame = shape.center_frame_world - shape.half_extent_frames_world - 1; maxFrame = shape.center_frame_world + shape.half_extent_frames_world + 1; minBin = freqToBinIndex(shape.center_freq_world - shape.half_extent_freq_world) - 1; // Approx bin range from world freq maxBin = freqToBinIndex(shape.center_freq_world + shape.half_extent_freq_world) + 1; // Approx bin range from world freq break; } minFrame = Math.max(0, minFrame); maxFrame = Math.min(targetSpecData.header.num_frames - 1, maxFrame); // Use targetSpecData.header.num_frames minBin = Math.max(0, minBin); maxBin = Math.min(dctSize - 1, maxBin); for (let f = minFrame; f <= maxFrame; f++) { for (let b = minBin; b <= maxBin; b++) { const p_world = vec2(f, binIndexToFreqLog(b)); let distance = Infinity; switch (shape.type) { case 'line': const a_line = vec2(shape.frame1_world, shape.freq1_world); const b_line = vec2(shape.frame2_world, shape.freq2_world); distance = sdSegment(p_world, a_line, b_line); break; case 'ellipse': const center_ellipse = vec2(shape.center_frame_world, shape.center_freq_world); const r_ellipse = vec2(shape.radius_frames_world, shape.radius_freq_world); distance = sdEllipse(sub(p_world, center_ellipse), r_ellipse); break; case 'noise_rect': const center_box = vec2(shape.center_frame_world, shape.center_freq_world); const r_box = vec2(shape.half_extent_frames_world, shape.half_extent_freq_world); distance = sdBox(sub(p_world, center_box), r_box); if (distance <= 0 && Math.random() < shape.density) { // Only add noise inside the box with density targetSpecData.data[f * dctSize + b] += (Math.random() * 2 - 1) * shape.amplitude; } break; } if (shape.type !== 'noise_rect') { // Noise is handled differently for amplitude const attenuation = Math.exp(-distance * distance * shape.falloff); targetSpecData.data[f * dctSize + b] += shape.amplitude * attenuation; } // Clamp final value targetSpecData.data[f * dctSize + b] = Math.max(-1, Math.min(1, targetSpecData.data[f * dctSize + b])); } } } // --- Undo/Redo Logic --- function addAction(action) { undoStack.push(action); if (undoStack.length > MAX_HISTORY_SIZE) { undoStack.shift(); } redoStack = []; updateUndoRedoButtons(); } function handleUndo() { if (undoStack.length === 0) { console.log('Undo stack is empty.'); return; } const actionToUndo = undoStack.pop(); actionToUndo.undo(); redoStack.push(actionToUndo); redrawCanvas(); updateUndoRedoButtons(); } function handleRedo() { if (redoStack.length === 0) { console.log('Redo stack is empty.'); return; } const actionToRedo = redoStack.pop(); actionToRedo.redo(); undoStack.push(actionToRedo); redrawCanvas(); updateUndoRedoButtons(); } function redrawCanvas() { console.log('Redrawing canvas...'); if (!originalSpecData) { ctx.clearRect(0, 0, canvas.width, canvas.height); ctx.fillStyle = '#ffffff'; ctx.fillRect(0, 0, canvas.width, canvas.height); return; } // Start with a fresh copy of the original data currentSpecData.data = new Float32Array(originalSpecData.data); // Replay all shapes from the `shapes` array to `currentSpecData` shapes.forEach(shape => { applyShapeToSpectrogram(shape, currentSpecData); }); drawSpectrogram(currentSpecData); } function updateUndoRedoButtons() { undoButton.disabled = undoStack.length === 0; redoButton.disabled = redoStack.length === 0; } // Initial setup for canvas size (can be updated on window resize) window.addEventListener('resize', () => { if (originalSpecData) { canvas.width = window.innerWidth * 0.7; canvas.height = 400; // Fixed height redrawCanvas(); } }); // Initial call to set button states updateUndoRedoButtons(); // --- Audio Playback Functions --- let currentAudioSource = null; // To stop currently playing audio async function playSpectrogramData(specData) { if (!specData || !specData.data || specData.header.num_frames === 0) { alert("No spectrogram data to play."); return; } if (currentAudioSource) { currentAudioSource.stop(); currentAudioSource.disconnect(); currentAudioSource = null; } const sampleRate = SAMPLE_RATE; // Fixed sample rate const numFrames = specData.header.num_frames; const totalAudioSamples = numFrames * dctSize; // Total samples in time domain const audioBuffer = audioContext.createBuffer(1, totalAudioSamples, sampleRate); const audioData = audioBuffer.getChannelData(0); // Mono channel // Convert spectrogram frames (frequency domain) to audio samples (time domain) for (let frameIndex = 0; frameIndex < numFrames; frameIndex++) { const spectralFrame = specData.data.slice(frameIndex * dctSize, (frameIndex + 1) * dctSize); const timeDomainFrame = javascript_idct_512(spectralFrame); // Apply Hanning window for smooth transitions for (let i = 0; i < dctSize; i++) { audioData[frameIndex * dctSize + i] = timeDomainFrame[i] * hanningWindowArray[i]; } } currentAudioSource = audioContext.createBufferSource(); currentAudioSource.buffer = audioBuffer; currentAudioSource.connect(audioContext.destination); currentAudioSource.start(); console.log(`Playing audio (Sample Rate: ${sampleRate}, Duration: ${audioBuffer.duration.toFixed(2)}s)`); }