Librosa

====

------
2015-07-08

Bug fixes
- Fixed alignment errors with `offset` and `duration` in `load()`
- Fixed an edge-padding issue with `decompose.hpss()` which resulted in percussive noise leaking into the harmonic component.
- Fixed stability issues with `ifgram()`, added options to suppress negative frequencies.
- Fixed scaling and padding errors in `feature.delta()`
- Fixed some errors in `librosa.note_to_hz()` string parsing
- Added robust range detection for `librosa.display.cmap`
- Fixed tick placement in `librosa.display.specshow`
- Fixed a low-frequency filter alignment error in `librosa.cqt`
- Added aliasing checks for `librosa.cqt` filterbanks
- Fixed corner cases in `peak_pick`
- Fixed bugs in `find_files()` with negative slicing
- Fixed tuning estimation errors
- Fixed octave numbering in to conform to scientific pitch notation

New features
- python 3 compatibility
- Deprecation and moved-function warnings
- added `norm=None` option to `util.normalize()`
- `segment.recurrence_to_lag`, `lag_to_recurrence`
- `core.hybrid_cqt()` and `core.pseudo_cqt()`
- `segment.timelag_filter`
- Efficiency enhancements for `cqt`
- Major rewrite and reformatting of documentation
- Improvements to `display.specshow`:
- added the `lag` axis format
- added the `tonnetz` axis format
- allow any combination of axis formats
- `effects.remix()`
- Added new time and frequency converters:
- `note_to_hz()`, `hz_to_note()`
- `frames_to_samples()`, `samples_to_frames()`
- `time_to_samples()`, `samples_to_time()`
- `core.zero_crossings`
- `util.match_events()`
- `segment.subsegment()` for segmentation refinement
- Functional examples in almost all docstrings
- improved numerical stability in `normalize()`
- audio validation checks
- `to_mono()`
- `librosa.cache` for storing pre-computed features
- Stereo output support in `write_wav`
- Added new feature extraction functions:
- `feature.spectral_contrast`
- `feature.spectral_bandwidth`
- `feature.spectral_centroid`
- `feature.spectral_rolloff`
- `feature.poly_features`
- `feature.rmse`
- `feature.zero_crossing_rate`
- `feature.tonnetz`
- Added `display.waveplot`

Other changes
- Internal refactoring and restructuring of submodules
- Removed the `chord` module
- input validation and better exception reporting for most functions
- Changed the default colormaps in `display`
- Changed default parameters in onset detection, beat tracking
- Changed default parameters in `cqt`
- `filters.constant_q` now returns filter lengths
- Chroma now starts at `C` by default, instead of `A`
- `pad_center` supports multi-dimensional input and `axis` parameter
- switched from `np.fft` to `scipy.fftpack` for FFT operations
- changed all librosa-generated exception to a new class librosa.ParameterError

Deprecated functions
- `util.buf_to_int`
- `output.frames_csv`
- `segment.structure_feature`
- `filters.logfrequency`
- `feature.logfsgram`

------
2015-02-18

Bug fixes
- Fixed bug 117: `librosa.segment.agglomerative` now returns a numpy.ndarray instead of a list
- Fixed bug 115: off-by-one error in `librosa.load` with fixed duration
- Fixed numerical underflow errors in `librosa.decompose.hpss`
- Fixed bug 104: `librosa.decompose.hpss` failed with silent, complex-valued input
- Fixed bug 103: `librosa.feature.estimate_tuning` fails when no bins exceed the threshold

Features
- New function `librosa.get_duration()` computes the duration of an audio signal or spectrogram-like input matrix
- `librosa.util.pad_center` now accepts multi-dimensional input

Other changes
- Adopted the ISC license
- Python 3 compatibility via futurize
- Fixed issue 102: segment.agglomerative no longer depends on the deprecated Ward module of sklearn; it now depends on the newer Agglomerative module.
- Issue 108: set character encoding on all source files
- Added dtype persistence for resample, stft, istft, and effects functions

====

------
2014-06-30

Bug fixes
- Fixed numpy array indices to force integer values
- `librosa.util.frame` now warns if the input data is non-contiguous
- Fixed a formatting error in `librosa.display.time_ticks()`
- Added a warning if `scikits.samplerate` is not detected

Features
- New module `librosa.chord` for training chord recognition models
- Parabolic interpolation piptracking `librosa.feature.piptrack()`
- `librosa.localmax()` now supports multi-dimensional slicing
- New example scripts
- Improved documentation
- Added the `librosa.util.FeatureExtractor` class, which allows librosa functions to act as feature extraction stages in `sklearn`
- New module `librosa.effects` for time-domain audio processing
- Added demo notebooks for the `librosa.effects` and `librosa.util.FeatureExtractor`
- Added a full-track audio example, `librosa.util.example_audio_file()`
- Added peak-frequency sorting of basis elements in `librosa.decompose.decompose()`

Other changes
- Spectrogram frames are now centered, rather than left-aligned. This removes the need for window correction in `librosa.frames_to_time()`
- Accelerated constant-Q transform `librosa.cqt()`
- PEP8 compliance
- Removed normalization from `librosa.feature.logfsgram()`
- Efficiency improvements by ensuring memory contiguity
- `librosa.logamplitude()` now supports functional reference power, in addition to scalar values
- Improved `librosa.feature.delta()`
- Additional padding options to `librosa.feature.stack_memory()`
- `librosa.cqt` and `librosa.feature.logfsgram` now use the same parameter formats `(fmin, n_bins, bins_per_octave)`.
- Updated demo notebook(s) to IPython 2.0
- Moved `perceptual_weighting()` from `librosa.feature` into `librosa`
- Moved `stack_memory()` from `librosa.segment` into `librosa.feature`
- Standardized `librosa.output.annotation` input format to match `mir_eval`
- Standardized variable names (e.g., `onset_envelope`).

------
2014-01-21

Bug fixes
- fixed an off-by-one error in `librosa.onset.onset_strength()`
- fixed a sign-flip error in `librosa.output.write_wav()`
- removed all mutable object default parameters

Features
- added option `centering` to `librosa.onset.onset_strength()` to resolve frame-centering issues with sliding window STFT
- added frame-center correction to `librosa.frames_to_time()` and `librosa.time_to_frames()`
- added `librosa.util.pad_center()`
- added `librosa.output.annotation()`
- added `librosa.output.times_csv()`
- accelerated `librosa.stft()` and `ifgram()`
- added `librosa.util.frame` for in-place signal framing
- `librosa.beat.beat_track` now supports user-supplied tempo
- added `librosa.util.normalize()`
- added `librosa.util.find_files()`
- added `librosa.util.axis_sort()`
- new module: `librosa.util()`
- `librosa.filters.constant_q` now support padding
- added boolean input support for `librosa.display.cmap()`
- speedup in `librosa.cqt()`

Other changes
- optimized default parameters for `librosa.onset.onset_detect`
- set `librosa.filters.mel` parameter `n_mels=128` by default
- `librosa.feature.chromagram()` and `logfsgram()` now use power instead of energy
- `librosa.display.specshow()` with `y_axis='chroma'` now labels as `pitch class`
- set `librosa.cqt` parameter `resolution=2` by default
- set `librosa.feature.chromagram` parameter `octwidth=2` by default