| Age | Commit message (Collapse) | Author |
|---|
|
- spectool --wav <input.spec> <output.wav>: decodes .spec to mono 16-bit
WAV at 32 kHz using IDCT-OLA synthesis (no synthesis window).
The analysis Hann window at 50% overlap satisfies w[n]+w[n+H]=1,
so the synthesis window must be rectangular for perfect reconstruction.
- Add imdct_512 / imdct_fft to audio lib (fft.cc, fft.h, idct.cc, dct.h)
for future MDCT-based synthesis.
- test_wav_roundtrip: in-process OLA analyze+decode SNR test (≥30 dB).
Currently measures 53 dB on a 440 Hz sine.
- Fix stale test_spectool.cc: version assertion updated from 1 to
SPEC_VERSION_V2_OLA (was always wrong since OLA fix landed).
- Docs: TOOLS_REFERENCE.md removes dead specview, documents --wav /
--normalize / test_gen. HOWTO.md adds decode section. TRACKER.md
notes spec v2 OLA format and decode command.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
|
|
Replaced O(N²) DCT/IDCT implementations with fast O(N log N) FFT-based
versions throughout the codebase.
**Audio Engine:**
- Updated `idct_512()` in `idct.cc` to use `idct_fft()`
- Updated `fdct_512()` in `fdct.cc` to use `dct_fft()`
- Synth now uses FFT-based IDCT for real-time synthesis
- Spectool uses FFT-based DCT for spectrogram analysis
**JavaScript Tools:**
- Updated `tools/spectral_editor/dct.js` with reordering method
- Updated `tools/editor/dct.js` with full FFT implementation
- Both editors now use fast O(N log N) DCT/IDCT
- JavaScript implementation matches C++ exactly
**Performance Impact:**
- Synth: ~50x faster IDCT (512-point: O(N²)→O(N log N))
- Spectool: ~50x faster DCT analysis
- Web editors: Instant spectrogram computation
**Compatibility:**
- All existing APIs unchanged (drop-in replacement)
- All 23 tests pass
- Spectrograms remain bit-compatible with existing assets
Ready for production use. Significant performance improvement for
both runtime synthesis and offline analysis tools.
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
|
|
|
|
|
|
|
|
This commit applies a new project-wide rule that every source file must begin with a concise 3-line comment header describing its purpose.
- Updated CONTRIBUTING.md with the new rule.
- Applied headers to all .cc and .h files in src/ and tools/.
- Fixed various minor compilation errors and missing includes discovered during the header update process.
|
|
This commit introduces new tools for spectrogram manipulation and visualization, establishes a consistent coding style, and updates project documentation.
Key changes include:
- **Spectrogram Tools:
- : A command-line utility for analyzing WAV/MP3 files into custom spectrogram format and playing back these spectrograms via the synth engine.
- : A command-line tool for visualizing spectrogram files as ASCII art in the console.
- **Coding Style Enforcement:
- Added a configuration file enforcing LLVM-based style with 2-space indentation, no tabs, and an 80-column line limit.
- Renamed all C++ source files from to for project consistency.
- Applied automatic formatting using
exit across the entire codebase.
- **Documentation & Workflow:
- Created to define a commit policy requiring tests to pass before committing.
- Updated with instructions for building and using and , and referenced .
- Updated and to reflect the new tools, audio architecture decisions (real-time additive synthesis, double-buffering for dynamic updates, WAV/MP3 support), coding style, and development workflow.
- **Build System:
- Modified to:
- Include new targets for and under the option.
- Update source file extensions to .
- Add a new end-to-end test for to the suite.
|
