| Age | Commit message (Collapse) | Author |
|---|
|
Implements a more robust partial tracking algorithm by using phase
coherence to validate and link spectral peaks across frames. This
significantly improves tracking accuracy, especially for crossing or
closely-spaced partials.
Key changes:
- : The STFT cache now computes and stores the phase for each
frequency bin alongside the magnitude.
- : The peak detection logic now interpolates the
phase for sub-bin accuracy.
- : The core tracking algorithm was replaced with a
phase-aware model. It predicts the expected phase for a partial in
the next frame and uses a cost function combining both frequency and
phase error to find the best match.
This implementation follows the design outlined in the new document
.
handoff(Gemini): Phase prediction implemented. Further tuning of the cost function weights may be beneficial.
|
|
- Fix mini-spectrum: log-scale frequency axis, per-pixel bin averaging,
red peak bars after extraction
- Fix key handlers swallowing digits in input fields
- Clamp hop size to min 64 to prevent hang
- Store maxDB in STFTCache, use it to normalize both mini-spectrum and
main spectrogram (fixes clipping at 0dB for pure tones)
- Add Test WAV console validation for 440/660Hz peaks
- Grayscale colormap for main spectrogram
handoff(Gemini): mq_editor display fixes complete, tests not affected
|
|
handoff(Claude): removed full spectrum storage from STFTCache frames;
getFFT() deleted; viewers use squaredAmplitude + 10*log10 directly.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
|
|
- STFTCache: cache squaredAmplitude (re²+im²) per frame, add getSquaredAmplitude(t)
- getMagnitudeDB uses cached sq amp (10*log10, no sqrt)
- detectPeaks uses squaredAmp from cache instead of recomputing FFT
- extractPartials: use cache frames, return {partials, frames}
- Press 'p' to toggle raw peak overlay in viewer
- threshold input: step=any, change event triggers re-extraction
- runExtraction() shared by button and threshold change
handoff(Claude): mq_partial peaks/cache refactor complete
|
|
Phase 2 - JS Synthesizer:
- Created mq_synth.js with replica oscillator bank
- Bezier curve evaluation (cubic De Casteljau algorithm)
- Replica synthesis: frequency spread, amplitude decay, phase jitter
- PCM buffer generation from extracted MQ partials
- Normalization to prevent clipping
- Key '1' plays synthesized audio, key '2' plays original
- Playback comparison with animated playhead
STFT Cache Optimization:
- Created STFTCache class in fft.js for pre-computed windowed FFT frames
- Clean interface: getFFT(t), getMagnitudeDB(t, freq), setHopSize()
- Pre-computes all frames on WAV load (eliminates redundant FFT calls)
- Dynamic cache update when hop size changes
- Shared across spectrogram, tooltip, and mini-spectrum viewer
- Significant performance improvement
Mini-Spectrum Viewer:
- Bottom-right overlay (200x100) matching spectral_editor style
- Real-time FFT display at playhead or mouse position
- 100-bar visualization with cyan-to-yellow gradient
- Updates during playback or mouse hover
Files:
- tools/mq_editor/mq_synth.js (new)
- tools/mq_editor/fft.js (STFTCache class added)
- tools/mq_editor/index.html (synthesis playback, cache integration)
- tools/mq_editor/viewer.js (cache-based rendering, spectrum viewer)
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
|
|
Implement McAulay-Quatieri sinusoidal analysis tool for audio compression.
New files:
- doc/SPECTRAL_BRUSH_2.md: Complete design doc (MQ algorithm, data format, synthesis, roadmap)
- tools/mq_editor/index.html: Web UI (file loader, params, canvas)
- tools/mq_editor/fft.js: Radix-2 Cooley-Tukey FFT (from spectral_editor)
- tools/mq_editor/mq_extract.js: MQ algorithm (peak detection, tracking, bezier fitting)
- tools/mq_editor/viewer.js: Visualization (spectrogram, partials, zoom, axes)
- tools/mq_editor/README.md: Usage and implementation status
Features:
- Load WAV → extract sinusoidal partials → fit cubic bezier curves
- Time-frequency spectrogram with hot colormap (0-16 kHz)
- Horizontal zoom (mousewheel) around mouse position
- Axis ticks with labels (time: seconds, freq: Hz/kHz)
- Mouse tooltip showing time/frequency coordinates
- Real-time adjustable MQ parameters (FFT size, hop, threshold)
Algorithm:
- STFT with Hann windows (2048 FFT, 512 hop)
- Peak detection with parabolic interpolation
- Birth/death/continuation tracking (50 Hz tolerance)
- Cubic bezier fitting (4 control points per trajectory)
Next: Phase 2 (JS synthesizer for audio preview)
handoff(Claude): MQ editor Phase 1 complete. Ready for synthesis implementation.
|
