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q268000
__beat_track_dp
test
def __beat_track_dp(localscore, period, tightness): """Core dynamic program for beat tracking""" backlink = np.zeros_like(localscore, dtype=int) cumscore = np.zeros_like(localscore) # Search range for previous beat window = np.arange(-2 * period, -np.round(period / 2) + 1, dtype=int) # Make a score window, which begins biased toward start_bpm and skewed if tightness <= 0: raise ParameterError('tightness must be strictly positive') txwt = -tightness * (np.log(-window / period) ** 2) # Are we on the first beat? first_beat = True for i, score_i in enumerate(localscore): # Are we reaching back before time 0? z_pad = np.maximum(0, min(- window[0], len(window))) # Search over all possible predecessors candidates = txwt.copy() candidates[z_pad:] = candidates[z_pad:] + cumscore[window[z_pad:]] # Find the best preceding beat beat_location = np.argmax(candidates) # Add the local score cumscore[i] = score_i + candidates[beat_location] # Special case the first onset. Stop if the localscore is small if first_beat and score_i < 0.01 * localscore.max(): backlink[i] = -1 else: backlink[i] = window[beat_location] first_beat = False # Update the time range window = window + 1 return backlink, cumscore
python
{ "resource": "" }
q268001
__last_beat
test
def __last_beat(cumscore): """Get the last beat from the cumulative score array""" maxes = util.localmax(cumscore) med_score = np.median(cumscore[np.argwhere(maxes)]) # The last of these is the last beat (since score generally increases) return np.argwhere((cumscore * maxes * 2 > med_score)).max()
python
{ "resource": "" }
q268002
recurrence_to_lag
test
def recurrence_to_lag(rec, pad=True, axis=-1): '''Convert a recurrence matrix into a lag matrix. `lag[i, j] == rec[i+j, j]` Parameters ---------- rec : np.ndarray, or scipy.sparse.spmatrix [shape=(n, n)] A (binary) recurrence matrix, as returned by `recurrence_matrix` pad : bool If False, `lag` matrix is square, which is equivalent to assuming that the signal repeats itself indefinitely. If True, `lag` is padded with `n` zeros, which eliminates the assumption of repetition. axis : int The axis to keep as the `time` axis. The alternate axis will be converted to lag coordinates. Returns ------- lag : np.ndarray The recurrence matrix in (lag, time) (if `axis=1`) or (time, lag) (if `axis=0`) coordinates Raises ------ ParameterError : if `rec` is non-square See Also -------- recurrence_matrix lag_to_recurrence Examples -------- >>> y, sr = librosa.load(librosa.util.example_audio_file()) >>> mfccs = librosa.feature.mfcc(y=y, sr=sr) >>> recurrence = librosa.segment.recurrence_matrix(mfccs) >>> lag_pad = librosa.segment.recurrence_to_lag(recurrence, pad=True) >>> lag_nopad = librosa.segment.recurrence_to_lag(recurrence, pad=False) >>> import matplotlib.pyplot as plt >>> plt.figure(figsize=(8, 4)) >>> plt.subplot(1, 2, 1) >>> librosa.display.specshow(lag_pad, x_axis='time', y_axis='lag') >>> plt.title('Lag (zero-padded)') >>> plt.subplot(1, 2, 2) >>> librosa.display.specshow(lag_nopad, x_axis='time') >>> plt.title('Lag (no padding)') >>> plt.tight_layout() ''' axis = np.abs(axis) if rec.ndim != 2 or rec.shape[0] != rec.shape[1]: raise ParameterError('non-square recurrence matrix shape: ' '{}'.format(rec.shape)) sparse = scipy.sparse.issparse(rec) roll_ax = None if sparse: roll_ax = 1 - axis lag_format = rec.format if axis == 0: rec = rec.tocsc() elif axis in (-1, 1): rec = rec.tocsr() t = rec.shape[axis] if sparse: if pad: kron = np.asarray([[1, 0]]).swapaxes(axis, 0) lag = scipy.sparse.kron(kron.astype(rec.dtype), rec, format='lil') else: lag = scipy.sparse.lil_matrix(rec) else: if pad: padding = [(0, 0), (0, 0)] padding[(1-axis)] = (0, t) lag = np.pad(rec, padding, mode='constant') else: lag = rec.copy() idx_slice = [slice(None)] * lag.ndim for i in range(1, t): idx_slice[axis] = i lag[tuple(idx_slice)] = util.roll_sparse(lag[tuple(idx_slice)], -i, axis=roll_ax) if sparse: return lag.asformat(lag_format) return np.ascontiguousarray(lag.T).T
python
{ "resource": "" }
q268003
lag_to_recurrence
test
def lag_to_recurrence(lag, axis=-1): '''Convert a lag matrix into a recurrence matrix. Parameters ---------- lag : np.ndarray or scipy.sparse.spmatrix A lag matrix, as produced by `recurrence_to_lag` axis : int The axis corresponding to the time dimension. The alternate axis will be interpreted in lag coordinates. Returns ------- rec : np.ndarray or scipy.sparse.spmatrix [shape=(n, n)] A recurrence matrix in (time, time) coordinates For sparse matrices, format will match that of `lag`. Raises ------ ParameterError : if `lag` does not have the correct shape See Also -------- recurrence_to_lag Examples -------- >>> y, sr = librosa.load(librosa.util.example_audio_file()) >>> mfccs = librosa.feature.mfcc(y=y, sr=sr) >>> recurrence = librosa.segment.recurrence_matrix(mfccs) >>> lag_pad = librosa.segment.recurrence_to_lag(recurrence, pad=True) >>> lag_nopad = librosa.segment.recurrence_to_lag(recurrence, pad=False) >>> rec_pad = librosa.segment.lag_to_recurrence(lag_pad) >>> rec_nopad = librosa.segment.lag_to_recurrence(lag_nopad) >>> import matplotlib.pyplot as plt >>> plt.figure(figsize=(8, 4)) >>> plt.subplot(2, 2, 1) >>> librosa.display.specshow(lag_pad, x_axis='time', y_axis='lag') >>> plt.title('Lag (zero-padded)') >>> plt.subplot(2, 2, 2) >>> librosa.display.specshow(lag_nopad, x_axis='time', y_axis='time') >>> plt.title('Lag (no padding)') >>> plt.subplot(2, 2, 3) >>> librosa.display.specshow(rec_pad, x_axis='time', y_axis='time') >>> plt.title('Recurrence (with padding)') >>> plt.subplot(2, 2, 4) >>> librosa.display.specshow(rec_nopad, x_axis='time', y_axis='time') >>> plt.title('Recurrence (without padding)') >>> plt.tight_layout() ''' if axis not in [0, 1, -1]: raise ParameterError('Invalid target axis: {}'.format(axis)) axis = np.abs(axis) if lag.ndim != 2 or (lag.shape[0] != lag.shape[1] and lag.shape[1 - axis] != 2 * lag.shape[axis]): raise ParameterError('Invalid lag matrix shape: {}'.format(lag.shape)) # Since lag must be 2-dimensional, abs(axis) = axis t = lag.shape[axis] sparse = scipy.sparse.issparse(lag) if sparse: rec = scipy.sparse.lil_matrix(lag) roll_ax = 1 - axis else: rec = lag.copy() roll_ax = None idx_slice = [slice(None)] * lag.ndim for i in range(1, t): idx_slice[axis] = i rec[tuple(idx_slice)] = util.roll_sparse(lag[tuple(idx_slice)], i, axis=roll_ax) sub_slice = [slice(None)] * rec.ndim sub_slice[1 - axis] = slice(t) rec = rec[tuple(sub_slice)] if sparse: return rec.asformat(lag.format) return np.ascontiguousarray(rec.T).T
python
{ "resource": "" }
q268004
timelag_filter
test
def timelag_filter(function, pad=True, index=0): '''Filtering in the time-lag domain. This is primarily useful for adapting image filters to operate on `recurrence_to_lag` output. Using `timelag_filter` is equivalent to the following sequence of operations: >>> data_tl = librosa.segment.recurrence_to_lag(data) >>> data_filtered_tl = function(data_tl) >>> data_filtered = librosa.segment.lag_to_recurrence(data_filtered_tl) Parameters ---------- function : callable The filtering function to wrap, e.g., `scipy.ndimage.median_filter` pad : bool Whether to zero-pad the structure feature matrix index : int >= 0 If `function` accepts input data as a positional argument, it should be indexed by `index` Returns ------- wrapped_function : callable A new filter function which applies in time-lag space rather than time-time space. Examples -------- Apply a 5-bin median filter to the diagonal of a recurrence matrix >>> y, sr = librosa.load(librosa.util.example_audio_file()) >>> chroma = librosa.feature.chroma_cqt(y=y, sr=sr) >>> rec = librosa.segment.recurrence_matrix(chroma) >>> from scipy.ndimage import median_filter >>> diagonal_median = librosa.segment.timelag_filter(median_filter) >>> rec_filtered = diagonal_median(rec, size=(1, 3), mode='mirror') Or with affinity weights >>> rec_aff = librosa.segment.recurrence_matrix(chroma, mode='affinity') >>> rec_aff_fil = diagonal_median(rec_aff, size=(1, 3), mode='mirror') >>> import matplotlib.pyplot as plt >>> plt.figure(figsize=(8,8)) >>> plt.subplot(2, 2, 1) >>> librosa.display.specshow(rec, y_axis='time') >>> plt.title('Raw recurrence matrix') >>> plt.subplot(2, 2, 2) >>> librosa.display.specshow(rec_filtered) >>> plt.title('Filtered recurrence matrix') >>> plt.subplot(2, 2, 3) >>> librosa.display.specshow(rec_aff, x_axis='time', y_axis='time', ... cmap='magma_r') >>> plt.title('Raw affinity matrix') >>> plt.subplot(2, 2, 4) >>> librosa.display.specshow(rec_aff_fil, x_axis='time', ... cmap='magma_r') >>> plt.title('Filtered affinity matrix') >>> plt.tight_layout() ''' def __my_filter(wrapped_f, *args, **kwargs): '''Decorator to wrap the filter''' # Map the input data into time-lag space args = list(args) args[index] = recurrence_to_lag(args[index], pad=pad) # Apply the filtering function result = wrapped_f(*args, **kwargs) # Map back into time-time and return return lag_to_recurrence(result) return decorator(__my_filter, function)
python
{ "resource": "" }
q268005
subsegment
test
def subsegment(data, frames, n_segments=4, axis=-1): '''Sub-divide a segmentation by feature clustering. Given a set of frame boundaries (`frames`), and a data matrix (`data`), each successive interval defined by `frames` is partitioned into `n_segments` by constrained agglomerative clustering. .. note:: If an interval spans fewer than `n_segments` frames, then each frame becomes a sub-segment. Parameters ---------- data : np.ndarray Data matrix to use in clustering frames : np.ndarray [shape=(n_boundaries,)], dtype=int, non-negative] Array of beat or segment boundaries, as provided by `librosa.beat.beat_track`, `librosa.onset.onset_detect`, or `agglomerative`. n_segments : int > 0 Maximum number of frames to sub-divide each interval. axis : int Axis along which to apply the segmentation. By default, the last index (-1) is taken. Returns ------- boundaries : np.ndarray [shape=(n_subboundaries,)] List of sub-divided segment boundaries See Also -------- agglomerative : Temporal segmentation librosa.onset.onset_detect : Onset detection librosa.beat.beat_track : Beat tracking Notes ----- This function caches at level 30. Examples -------- Load audio, detect beat frames, and subdivide in twos by CQT >>> y, sr = librosa.load(librosa.util.example_audio_file(), duration=8) >>> tempo, beats = librosa.beat.beat_track(y=y, sr=sr, hop_length=512) >>> beat_times = librosa.frames_to_time(beats, sr=sr, hop_length=512) >>> cqt = np.abs(librosa.cqt(y, sr=sr, hop_length=512)) >>> subseg = librosa.segment.subsegment(cqt, beats, n_segments=2) >>> subseg_t = librosa.frames_to_time(subseg, sr=sr, hop_length=512) >>> subseg array([ 0, 2, 4, 21, 23, 26, 43, 55, 63, 72, 83, 97, 102, 111, 122, 137, 142, 153, 162, 180, 182, 185, 202, 210, 221, 231, 241, 256, 261, 271, 281, 296, 301, 310, 320, 339, 341, 344, 361, 368, 382, 389, 401, 416, 420, 430, 436, 451, 456, 465, 476, 489, 496, 503, 515, 527, 535, 544, 553, 558, 571, 578, 590, 607, 609, 638]) >>> import matplotlib.pyplot as plt >>> plt.figure() >>> librosa.display.specshow(librosa.amplitude_to_db(cqt, ... ref=np.max), ... y_axis='cqt_hz', x_axis='time') >>> lims = plt.gca().get_ylim() >>> plt.vlines(beat_times, lims[0], lims[1], color='lime', alpha=0.9, ... linewidth=2, label='Beats') >>> plt.vlines(subseg_t, lims[0], lims[1], color='linen', linestyle='--', ... linewidth=1.5, alpha=0.5, label='Sub-beats') >>> plt.legend(frameon=True, shadow=True) >>> plt.title('CQT + Beat and sub-beat markers') >>> plt.tight_layout() ''' frames = util.fix_frames(frames, x_min=0, x_max=data.shape[axis], pad=True) if n_segments < 1: raise ParameterError('n_segments must be a positive integer') boundaries = [] idx_slices = [slice(None)] * data.ndim for seg_start, seg_end in zip(frames[:-1], frames[1:]): idx_slices[axis] = slice(seg_start, seg_end) boundaries.extend(seg_start + agglomerative(data[tuple(idx_slices)], min(seg_end - seg_start, n_segments), axis=axis)) return np.ascontiguousarray(boundaries)
python
{ "resource": "" }
q268006
agglomerative
test
def agglomerative(data, k, clusterer=None, axis=-1): """Bottom-up temporal segmentation. Use a temporally-constrained agglomerative clustering routine to partition `data` into `k` contiguous segments. Parameters ---------- data : np.ndarray data to cluster k : int > 0 [scalar] number of segments to produce clusterer : sklearn.cluster.AgglomerativeClustering, optional An optional AgglomerativeClustering object. If `None`, a constrained Ward object is instantiated. axis : int axis along which to cluster. By default, the last axis (-1) is chosen. Returns ------- boundaries : np.ndarray [shape=(k,)] left-boundaries (frame numbers) of detected segments. This will always include `0` as the first left-boundary. See Also -------- sklearn.cluster.AgglomerativeClustering Examples -------- Cluster by chroma similarity, break into 20 segments >>> y, sr = librosa.load(librosa.util.example_audio_file(), duration=15) >>> chroma = librosa.feature.chroma_cqt(y=y, sr=sr) >>> bounds = librosa.segment.agglomerative(chroma, 20) >>> bound_times = librosa.frames_to_time(bounds, sr=sr) >>> bound_times array([ 0. , 1.672, 2.322, 2.624, 3.251, 3.506, 4.18 , 5.387, 6.014, 6.293, 6.943, 7.198, 7.848, 9.033, 9.706, 9.961, 10.635, 10.89 , 11.54 , 12.539]) Plot the segmentation over the chromagram >>> import matplotlib.pyplot as plt >>> plt.figure() >>> librosa.display.specshow(chroma, y_axis='chroma', x_axis='time') >>> plt.vlines(bound_times, 0, chroma.shape[0], color='linen', linestyle='--', ... linewidth=2, alpha=0.9, label='Segment boundaries') >>> plt.axis('tight') >>> plt.legend(frameon=True, shadow=True) >>> plt.title('Power spectrogram') >>> plt.tight_layout() """ # Make sure we have at least two dimensions data = np.atleast_2d(data) # Swap data index to position 0 data = np.swapaxes(data, axis, 0) # Flatten the features n = data.shape[0] data = data.reshape((n, -1)) if clusterer is None: # Connect the temporal connectivity graph grid = sklearn.feature_extraction.image.grid_to_graph(n_x=n, n_y=1, n_z=1) # Instantiate the clustering object clusterer = sklearn.cluster.AgglomerativeClustering(n_clusters=k, connectivity=grid, memory=cache.memory) # Fit the model clusterer.fit(data) # Find the change points from the labels boundaries = [0] boundaries.extend( list(1 + np.nonzero(np.diff(clusterer.labels_))[0].astype(int))) return np.asarray(boundaries)
python
{ "resource": "" }
q268007
path_enhance
test
def path_enhance(R, n, window='hann', max_ratio=2.0, min_ratio=None, n_filters=7, zero_mean=False, clip=True, **kwargs): '''Multi-angle path enhancement for self- and cross-similarity matrices. This function convolves multiple diagonal smoothing filters with a self-similarity (or recurrence) matrix R, and aggregates the result by an element-wise maximum. Technically, the output is a matrix R_smooth such that `R_smooth[i, j] = max_theta (R * filter_theta)[i, j]` where `*` denotes 2-dimensional convolution, and `filter_theta` is a smoothing filter at orientation theta. This is intended to provide coherent temporal smoothing of self-similarity matrices when there are changes in tempo. Smoothing filters are generated at evenly spaced orientations between min_ratio and max_ratio. This function is inspired by the multi-angle path enhancement of [1]_, but differs by modeling tempo differences in the space of similarity matrices rather than re-sampling the underlying features prior to generating the self-similarity matrix. .. [1] Müller, Meinard and Frank Kurth. "Enhancing similarity matrices for music audio analysis." 2006 IEEE International Conference on Acoustics Speech and Signal Processing Proceedings. Vol. 5. IEEE, 2006. .. note:: if using recurrence_matrix to construct the input similarity matrix, be sure to include the main diagonal by setting `self=True`. Otherwise, the diagonal will be suppressed, and this is likely to produce discontinuities which will pollute the smoothing filter response. Parameters ---------- R : np.ndarray The self- or cross-similarity matrix to be smoothed. Note: sparse inputs are not supported. n : int > 0 The length of the smoothing filter window : window specification The type of smoothing filter to use. See `filters.get_window` for more information on window specification formats. max_ratio : float > 0 The maximum tempo ratio to support min_ratio : float > 0 The minimum tempo ratio to support. If not provided, it will default to `1/max_ratio` n_filters : int >= 1 The number of different smoothing filters to use, evenly spaced between `min_ratio` and `max_ratio`. If `min_ratio = 1/max_ratio` (the default), using an odd number of filters will ensure that the main diagonal (ratio=1) is included. zero_mean : bool By default, the smoothing filters are non-negative and sum to one (i.e. are averaging filters). If `zero_mean=True`, then the smoothing filters are made to sum to zero by subtracting a constant value from the non-diagonal coordinates of the filter. This is primarily useful for suppressing blocks while enhancing diagonals. clip : bool If True, the smoothed similarity matrix will be thresholded at 0, and will not contain negative entries. kwargs : additional keyword arguments Additional arguments to pass to `scipy.ndimage.convolve` Returns ------- R_smooth : np.ndarray, shape=R.shape The smoothed self- or cross-similarity matrix See Also -------- filters.diagonal_filter recurrence_matrix Examples -------- Use a 51-frame diagonal smoothing filter to enhance paths in a recurrence matrix >>> y, sr = librosa.load(librosa.util.example_audio_file(), duration=30) >>> chroma = librosa.feature.chroma_cqt(y=y, sr=sr) >>> rec = librosa.segment.recurrence_matrix(chroma, mode='affinity', self=True) >>> rec_smooth = librosa.segment.path_enhance(rec, 51, window='hann', n_filters=7) Plot the recurrence matrix before and after smoothing >>> import matplotlib.pyplot as plt >>> plt.figure(figsize=(8, 4)) >>> plt.subplot(1,2,1) >>> librosa.display.specshow(rec, x_axis='time', y_axis='time') >>> plt.title('Unfiltered recurrence') >>> plt.subplot(1,2,2) >>> librosa.display.specshow(rec_smooth, x_axis='time', y_axis='time') >>> plt.title('Multi-angle enhanced recurrence') >>> plt.tight_layout() ''' if min_ratio is None: min_ratio = 1./max_ratio elif min_ratio > max_ratio: raise ParameterError('min_ratio={} cannot exceed max_ratio={}'.format(min_ratio, max_ratio)) R_smooth = None for ratio in np.logspace(np.log2(min_ratio), np.log2(max_ratio), num=n_filters, base=2): kernel = diagonal_filter(window, n, slope=ratio, zero_mean=zero_mean) if R_smooth is None: R_smooth = scipy.ndimage.convolve(R, kernel, **kwargs) else: # Compute the point-wise maximum in-place np.maximum(R_smooth, scipy.ndimage.convolve(R, kernel, **kwargs), out=R_smooth) if clip: # Clip the output in-place np.clip(R_smooth, 0, None, out=R_smooth) return R_smooth
python
{ "resource": "" }
q268008
onset_detect
test
def onset_detect(input_file, output_csv): '''Onset detection function :parameters: - input_file : str Path to input audio file (wav, mp3, m4a, flac, etc.) - output_file : str Path to save onset timestamps as a CSV file ''' # 1. load the wav file and resample to 22.050 KHz print('Loading ', input_file) y, sr = librosa.load(input_file, sr=22050) # Use a default hop size of 512 frames @ 22KHz ~= 23ms hop_length = 512 # 2. run onset detection print('Detecting onsets...') onsets = librosa.onset.onset_detect(y=y, sr=sr, hop_length=hop_length) print("Found {:d} onsets.".format(onsets.shape[0])) # 3. save output # 'beats' will contain the frame numbers of beat events. onset_times = librosa.frames_to_time(onsets, sr=sr, hop_length=hop_length) print('Saving output to ', output_csv) librosa.output.times_csv(output_csv, onset_times) print('done!')
python
{ "resource": "" }
q268009
frame
test
def frame(y, frame_length=2048, hop_length=512): '''Slice a time series into overlapping frames. This implementation uses low-level stride manipulation to avoid redundant copies of the time series data. Parameters ---------- y : np.ndarray [shape=(n,)] Time series to frame. Must be one-dimensional and contiguous in memory. frame_length : int > 0 [scalar] Length of the frame in samples hop_length : int > 0 [scalar] Number of samples to hop between frames Returns ------- y_frames : np.ndarray [shape=(frame_length, N_FRAMES)] An array of frames sampled from `y`: `y_frames[i, j] == y[j * hop_length + i]` Raises ------ ParameterError If `y` is not contiguous in memory, not an `np.ndarray`, or not one-dimensional. See `np.ascontiguous()` for details. If `hop_length < 1`, frames cannot advance. If `len(y) < frame_length`. Examples -------- Extract 2048-sample frames from `y` with a hop of 64 samples per frame >>> y, sr = librosa.load(librosa.util.example_audio_file()) >>> librosa.util.frame(y, frame_length=2048, hop_length=64) array([[ -9.216e-06, 7.710e-06, ..., -2.117e-06, -4.362e-07], [ 2.518e-06, -6.294e-06, ..., -1.775e-05, -6.365e-06], ..., [ -7.429e-04, 5.173e-03, ..., 1.105e-05, -5.074e-06], [ 2.169e-03, 4.867e-03, ..., 3.666e-06, -5.571e-06]], dtype=float32) ''' if not isinstance(y, np.ndarray): raise ParameterError('Input must be of type numpy.ndarray, ' 'given type(y)={}'.format(type(y))) if y.ndim != 1: raise ParameterError('Input must be one-dimensional, ' 'given y.ndim={}'.format(y.ndim)) if len(y) < frame_length: raise ParameterError('Buffer is too short (n={:d})' ' for frame_length={:d}'.format(len(y), frame_length)) if hop_length < 1: raise ParameterError('Invalid hop_length: {:d}'.format(hop_length)) if not y.flags['C_CONTIGUOUS']: raise ParameterError('Input buffer must be contiguous.') # Compute the number of frames that will fit. The end may get truncated. n_frames = 1 + int((len(y) - frame_length) / hop_length) # Vertical stride is one sample # Horizontal stride is `hop_length` samples y_frames = as_strided(y, shape=(frame_length, n_frames), strides=(y.itemsize, hop_length * y.itemsize)) return y_frames
python
{ "resource": "" }
q268010
valid_audio
test
def valid_audio(y, mono=True): '''Validate whether a variable contains valid, mono audio data. Parameters ---------- y : np.ndarray The input data to validate mono : bool Whether or not to force monophonic audio Returns ------- valid : bool True if all tests pass Raises ------ ParameterError If `y` fails to meet the following criteria: - `type(y)` is `np.ndarray` - `y.dtype` is floating-point - `mono == True` and `y.ndim` is not 1 - `mono == False` and `y.ndim` is not 1 or 2 - `np.isfinite(y).all()` is not True Notes ----- This function caches at level 20. Examples -------- >>> # Only allow monophonic signals >>> y, sr = librosa.load(librosa.util.example_audio_file()) >>> librosa.util.valid_audio(y) True >>> # If we want to allow stereo signals >>> y, sr = librosa.load(librosa.util.example_audio_file(), mono=False) >>> librosa.util.valid_audio(y, mono=False) True ''' if not isinstance(y, np.ndarray): raise ParameterError('data must be of type numpy.ndarray') if not np.issubdtype(y.dtype, np.floating): raise ParameterError('data must be floating-point') if mono and y.ndim != 1: raise ParameterError('Invalid shape for monophonic audio: ' 'ndim={:d}, shape={}'.format(y.ndim, y.shape)) elif y.ndim > 2 or y.ndim == 0: raise ParameterError('Audio must have shape (samples,) or (channels, samples). ' 'Received shape={}'.format(y.shape)) if not np.isfinite(y).all(): raise ParameterError('Audio buffer is not finite everywhere') return True
python
{ "resource": "" }
q268011
valid_int
test
def valid_int(x, cast=None): '''Ensure that an input value is integer-typed. This is primarily useful for ensuring integrable-valued array indices. Parameters ---------- x : number A scalar value to be cast to int cast : function [optional] A function to modify `x` before casting. Default: `np.floor` Returns ------- x_int : int `x_int = int(cast(x))` Raises ------ ParameterError If `cast` is provided and is not callable. ''' if cast is None: cast = np.floor if not six.callable(cast): raise ParameterError('cast parameter must be callable') return int(cast(x))
python
{ "resource": "" }
q268012
fix_length
test
def fix_length(data, size, axis=-1, **kwargs): '''Fix the length an array `data` to exactly `size`. If `data.shape[axis] < n`, pad according to the provided kwargs. By default, `data` is padded with trailing zeros. Examples -------- >>> y = np.arange(7) >>> # Default: pad with zeros >>> librosa.util.fix_length(y, 10) array([0, 1, 2, 3, 4, 5, 6, 0, 0, 0]) >>> # Trim to a desired length >>> librosa.util.fix_length(y, 5) array([0, 1, 2, 3, 4]) >>> # Use edge-padding instead of zeros >>> librosa.util.fix_length(y, 10, mode='edge') array([0, 1, 2, 3, 4, 5, 6, 6, 6, 6]) Parameters ---------- data : np.ndarray array to be length-adjusted size : int >= 0 [scalar] desired length of the array axis : int, <= data.ndim axis along which to fix length kwargs : additional keyword arguments Parameters to `np.pad()` Returns ------- data_fixed : np.ndarray [shape=data.shape] `data` either trimmed or padded to length `size` along the specified axis. See Also -------- numpy.pad ''' kwargs.setdefault('mode', 'constant') n = data.shape[axis] if n > size: slices = [slice(None)] * data.ndim slices[axis] = slice(0, size) return data[tuple(slices)] elif n < size: lengths = [(0, 0)] * data.ndim lengths[axis] = (0, size - n) return np.pad(data, lengths, **kwargs) return data
python
{ "resource": "" }
q268013
axis_sort
test
def axis_sort(S, axis=-1, index=False, value=None): '''Sort an array along its rows or columns. Examples -------- Visualize NMF output for a spectrogram S >>> # Sort the columns of W by peak frequency bin >>> y, sr = librosa.load(librosa.util.example_audio_file()) >>> S = np.abs(librosa.stft(y)) >>> W, H = librosa.decompose.decompose(S, n_components=32) >>> W_sort = librosa.util.axis_sort(W) Or sort by the lowest frequency bin >>> W_sort = librosa.util.axis_sort(W, value=np.argmin) Or sort the rows instead of the columns >>> W_sort_rows = librosa.util.axis_sort(W, axis=0) Get the sorting index also, and use it to permute the rows of H >>> W_sort, idx = librosa.util.axis_sort(W, index=True) >>> H_sort = H[idx, :] >>> import matplotlib.pyplot as plt >>> plt.figure() >>> plt.subplot(2, 2, 1) >>> librosa.display.specshow(librosa.amplitude_to_db(W, ref=np.max), ... y_axis='log') >>> plt.title('W') >>> plt.subplot(2, 2, 2) >>> librosa.display.specshow(H, x_axis='time') >>> plt.title('H') >>> plt.subplot(2, 2, 3) >>> librosa.display.specshow(librosa.amplitude_to_db(W_sort, ... ref=np.max), ... y_axis='log') >>> plt.title('W sorted') >>> plt.subplot(2, 2, 4) >>> librosa.display.specshow(H_sort, x_axis='time') >>> plt.title('H sorted') >>> plt.tight_layout() Parameters ---------- S : np.ndarray [shape=(d, n)] Array to be sorted axis : int [scalar] The axis along which to compute the sorting values - `axis=0` to sort rows by peak column index - `axis=1` to sort columns by peak row index index : boolean [scalar] If true, returns the index array as well as the permuted data. value : function function to return the index corresponding to the sort order. Default: `np.argmax`. Returns ------- S_sort : np.ndarray [shape=(d, n)] `S` with the columns or rows permuted in sorting order idx : np.ndarray (optional) [shape=(d,) or (n,)] If `index == True`, the sorting index used to permute `S`. Length of `idx` corresponds to the selected `axis`. Raises ------ ParameterError If `S` does not have exactly 2 dimensions (`S.ndim != 2`) ''' if value is None: value = np.argmax if S.ndim != 2: raise ParameterError('axis_sort is only defined for 2D arrays') bin_idx = value(S, axis=np.mod(1-axis, S.ndim)) idx = np.argsort(bin_idx) sort_slice = [slice(None)] * S.ndim sort_slice[axis] = idx if index: return S[tuple(sort_slice)], idx else: return S[tuple(sort_slice)]
python
{ "resource": "" }
q268014
normalize
test
def normalize(S, norm=np.inf, axis=0, threshold=None, fill=None): '''Normalize an array along a chosen axis. Given a norm (described below) and a target axis, the input array is scaled so that `norm(S, axis=axis) == 1` For example, `axis=0` normalizes each column of a 2-d array by aggregating over the rows (0-axis). Similarly, `axis=1` normalizes each row of a 2-d array. This function also supports thresholding small-norm slices: any slice (i.e., row or column) with norm below a specified `threshold` can be left un-normalized, set to all-zeros, or filled with uniform non-zero values that normalize to 1. Note: the semantics of this function differ from `scipy.linalg.norm` in two ways: multi-dimensional arrays are supported, but matrix-norms are not. Parameters ---------- S : np.ndarray The matrix to normalize norm : {np.inf, -np.inf, 0, float > 0, None} - `np.inf` : maximum absolute value - `-np.inf` : mininum absolute value - `0` : number of non-zeros (the support) - float : corresponding l_p norm See `scipy.linalg.norm` for details. - None : no normalization is performed axis : int [scalar] Axis along which to compute the norm. threshold : number > 0 [optional] Only the columns (or rows) with norm at least `threshold` are normalized. By default, the threshold is determined from the numerical precision of `S.dtype`. fill : None or bool If None, then columns (or rows) with norm below `threshold` are left as is. If False, then columns (rows) with norm below `threshold` are set to 0. If True, then columns (rows) with norm below `threshold` are filled uniformly such that the corresponding norm is 1. .. note:: `fill=True` is incompatible with `norm=0` because no uniform vector exists with l0 "norm" equal to 1. Returns ------- S_norm : np.ndarray [shape=S.shape] Normalized array Raises ------ ParameterError If `norm` is not among the valid types defined above If `S` is not finite If `fill=True` and `norm=0` See Also -------- scipy.linalg.norm Notes ----- This function caches at level 40. Examples -------- >>> # Construct an example matrix >>> S = np.vander(np.arange(-2.0, 2.0)) >>> S array([[-8., 4., -2., 1.], [-1., 1., -1., 1.], [ 0., 0., 0., 1.], [ 1., 1., 1., 1.]]) >>> # Max (l-infinity)-normalize the columns >>> librosa.util.normalize(S) array([[-1. , 1. , -1. , 1. ], [-0.125, 0.25 , -0.5 , 1. ], [ 0. , 0. , 0. , 1. ], [ 0.125, 0.25 , 0.5 , 1. ]]) >>> # Max (l-infinity)-normalize the rows >>> librosa.util.normalize(S, axis=1) array([[-1. , 0.5 , -0.25 , 0.125], [-1. , 1. , -1. , 1. ], [ 0. , 0. , 0. , 1. ], [ 1. , 1. , 1. , 1. ]]) >>> # l1-normalize the columns >>> librosa.util.normalize(S, norm=1) array([[-0.8 , 0.667, -0.5 , 0.25 ], [-0.1 , 0.167, -0.25 , 0.25 ], [ 0. , 0. , 0. , 0.25 ], [ 0.1 , 0.167, 0.25 , 0.25 ]]) >>> # l2-normalize the columns >>> librosa.util.normalize(S, norm=2) array([[-0.985, 0.943, -0.816, 0.5 ], [-0.123, 0.236, -0.408, 0.5 ], [ 0. , 0. , 0. , 0.5 ], [ 0.123, 0.236, 0.408, 0.5 ]]) >>> # Thresholding and filling >>> S[:, -1] = 1e-308 >>> S array([[ -8.000e+000, 4.000e+000, -2.000e+000, 1.000e-308], [ -1.000e+000, 1.000e+000, -1.000e+000, 1.000e-308], [ 0.000e+000, 0.000e+000, 0.000e+000, 1.000e-308], [ 1.000e+000, 1.000e+000, 1.000e+000, 1.000e-308]]) >>> # By default, small-norm columns are left untouched >>> librosa.util.normalize(S) array([[ -1.000e+000, 1.000e+000, -1.000e+000, 1.000e-308], [ -1.250e-001, 2.500e-001, -5.000e-001, 1.000e-308], [ 0.000e+000, 0.000e+000, 0.000e+000, 1.000e-308], [ 1.250e-001, 2.500e-001, 5.000e-001, 1.000e-308]]) >>> # Small-norm columns can be zeroed out >>> librosa.util.normalize(S, fill=False) array([[-1. , 1. , -1. , 0. ], [-0.125, 0.25 , -0.5 , 0. ], [ 0. , 0. , 0. , 0. ], [ 0.125, 0.25 , 0.5 , 0. ]]) >>> # Or set to constant with unit-norm >>> librosa.util.normalize(S, fill=True) array([[-1. , 1. , -1. , 1. ], [-0.125, 0.25 , -0.5 , 1. ], [ 0. , 0. , 0. , 1. ], [ 0.125, 0.25 , 0.5 , 1. ]]) >>> # With an l1 norm instead of max-norm >>> librosa.util.normalize(S, norm=1, fill=True) array([[-0.8 , 0.667, -0.5 , 0.25 ], [-0.1 , 0.167, -0.25 , 0.25 ], [ 0. , 0. , 0. , 0.25 ], [ 0.1 , 0.167, 0.25 , 0.25 ]]) ''' # Avoid div-by-zero if threshold is None: threshold = tiny(S) elif threshold <= 0: raise ParameterError('threshold={} must be strictly ' 'positive'.format(threshold)) if fill not in [None, False, True]: raise ParameterError('fill={} must be None or boolean'.format(fill)) if not np.all(np.isfinite(S)): raise ParameterError('Input must be finite') # All norms only depend on magnitude, let's do that first mag = np.abs(S).astype(np.float) # For max/min norms, filling with 1 works fill_norm = 1 if norm == np.inf: length = np.max(mag, axis=axis, keepdims=True) elif norm == -np.inf: length = np.min(mag, axis=axis, keepdims=True) elif norm == 0: if fill is True: raise ParameterError('Cannot normalize with norm=0 and fill=True') length = np.sum(mag > 0, axis=axis, keepdims=True, dtype=mag.dtype) elif np.issubdtype(type(norm), np.number) and norm > 0: length = np.sum(mag**norm, axis=axis, keepdims=True)**(1./norm) if axis is None: fill_norm = mag.size**(-1./norm) else: fill_norm = mag.shape[axis]**(-1./norm) elif norm is None: return S else: raise ParameterError('Unsupported norm: {}'.format(repr(norm))) # indices where norm is below the threshold small_idx = length < threshold Snorm = np.empty_like(S) if fill is None: # Leave small indices un-normalized length[small_idx] = 1.0 Snorm[:] = S / length elif fill: # If we have a non-zero fill value, we locate those entries by # doing a nan-divide. # If S was finite, then length is finite (except for small positions) length[small_idx] = np.nan Snorm[:] = S / length Snorm[np.isnan(Snorm)] = fill_norm else: # Set small values to zero by doing an inf-divide. # This is safe (by IEEE-754) as long as S is finite. length[small_idx] = np.inf Snorm[:] = S / length return Snorm
python
{ "resource": "" }
q268015
localmax
test
def localmax(x, axis=0): """Find local maxima in an array `x`. An element `x[i]` is considered a local maximum if the following conditions are met: - `x[i] > x[i-1]` - `x[i] >= x[i+1]` Note that the first condition is strict, and that the first element `x[0]` will never be considered as a local maximum. Examples -------- >>> x = np.array([1, 0, 1, 2, -1, 0, -2, 1]) >>> librosa.util.localmax(x) array([False, False, False, True, False, True, False, True], dtype=bool) >>> # Two-dimensional example >>> x = np.array([[1,0,1], [2, -1, 0], [2, 1, 3]]) >>> librosa.util.localmax(x, axis=0) array([[False, False, False], [ True, False, False], [False, True, True]], dtype=bool) >>> librosa.util.localmax(x, axis=1) array([[False, False, True], [False, False, True], [False, False, True]], dtype=bool) Parameters ---------- x : np.ndarray [shape=(d1,d2,...)] input vector or array axis : int axis along which to compute local maximality Returns ------- m : np.ndarray [shape=x.shape, dtype=bool] indicator array of local maximality along `axis` """ paddings = [(0, 0)] * x.ndim paddings[axis] = (1, 1) x_pad = np.pad(x, paddings, mode='edge') inds1 = [slice(None)] * x.ndim inds1[axis] = slice(0, -2) inds2 = [slice(None)] * x.ndim inds2[axis] = slice(2, x_pad.shape[axis]) return (x > x_pad[tuple(inds1)]) & (x >= x_pad[tuple(inds2)])
python
{ "resource": "" }
q268016
peak_pick
test
def peak_pick(x, pre_max, post_max, pre_avg, post_avg, delta, wait): '''Uses a flexible heuristic to pick peaks in a signal. A sample n is selected as an peak if the corresponding x[n] fulfills the following three conditions: 1. `x[n] == max(x[n - pre_max:n + post_max])` 2. `x[n] >= mean(x[n - pre_avg:n + post_avg]) + delta` 3. `n - previous_n > wait` where `previous_n` is the last sample picked as a peak (greedily). This implementation is based on [1]_ and [2]_. .. [1] Boeck, Sebastian, Florian Krebs, and Markus Schedl. "Evaluating the Online Capabilities of Onset Detection Methods." ISMIR. 2012. .. [2] https://github.com/CPJKU/onset_detection/blob/master/onset_program.py Parameters ---------- x : np.ndarray [shape=(n,)] input signal to peak picks from pre_max : int >= 0 [scalar] number of samples before `n` over which max is computed post_max : int >= 1 [scalar] number of samples after `n` over which max is computed pre_avg : int >= 0 [scalar] number of samples before `n` over which mean is computed post_avg : int >= 1 [scalar] number of samples after `n` over which mean is computed delta : float >= 0 [scalar] threshold offset for mean wait : int >= 0 [scalar] number of samples to wait after picking a peak Returns ------- peaks : np.ndarray [shape=(n_peaks,), dtype=int] indices of peaks in `x` Raises ------ ParameterError If any input lies outside its defined range Examples -------- >>> y, sr = librosa.load(librosa.util.example_audio_file(), duration=15) >>> onset_env = librosa.onset.onset_strength(y=y, sr=sr, ... hop_length=512, ... aggregate=np.median) >>> peaks = librosa.util.peak_pick(onset_env, 3, 3, 3, 5, 0.5, 10) >>> peaks array([ 4, 23, 73, 102, 142, 162, 182, 211, 261, 301, 320, 331, 348, 368, 382, 396, 411, 431, 446, 461, 476, 491, 510, 525, 536, 555, 570, 590, 609, 625, 639]) >>> import matplotlib.pyplot as plt >>> times = librosa.frames_to_time(np.arange(len(onset_env)), ... sr=sr, hop_length=512) >>> plt.figure() >>> ax = plt.subplot(2, 1, 2) >>> D = librosa.stft(y) >>> librosa.display.specshow(librosa.amplitude_to_db(D, ref=np.max), ... y_axis='log', x_axis='time') >>> plt.subplot(2, 1, 1, sharex=ax) >>> plt.plot(times, onset_env, alpha=0.8, label='Onset strength') >>> plt.vlines(times[peaks], 0, ... onset_env.max(), color='r', alpha=0.8, ... label='Selected peaks') >>> plt.legend(frameon=True, framealpha=0.8) >>> plt.axis('tight') >>> plt.tight_layout() ''' if pre_max < 0: raise ParameterError('pre_max must be non-negative') if pre_avg < 0: raise ParameterError('pre_avg must be non-negative') if delta < 0: raise ParameterError('delta must be non-negative') if wait < 0: raise ParameterError('wait must be non-negative') if post_max <= 0: raise ParameterError('post_max must be positive') if post_avg <= 0: raise ParameterError('post_avg must be positive') if x.ndim != 1: raise ParameterError('input array must be one-dimensional') # Ensure valid index types pre_max = valid_int(pre_max, cast=np.ceil) post_max = valid_int(post_max, cast=np.ceil) pre_avg = valid_int(pre_avg, cast=np.ceil) post_avg = valid_int(post_avg, cast=np.ceil) wait = valid_int(wait, cast=np.ceil) # Get the maximum of the signal over a sliding window max_length = pre_max + post_max max_origin = np.ceil(0.5 * (pre_max - post_max)) # Using mode='constant' and cval=x.min() effectively truncates # the sliding window at the boundaries mov_max = scipy.ndimage.filters.maximum_filter1d(x, int(max_length), mode='constant', origin=int(max_origin), cval=x.min()) # Get the mean of the signal over a sliding window avg_length = pre_avg + post_avg avg_origin = np.ceil(0.5 * (pre_avg - post_avg)) # Here, there is no mode which results in the behavior we want, # so we'll correct below. mov_avg = scipy.ndimage.filters.uniform_filter1d(x, int(avg_length), mode='nearest', origin=int(avg_origin)) # Correct sliding average at the beginning n = 0 # Only need to correct in the range where the window needs to be truncated while n - pre_avg < 0 and n < x.shape[0]: # This just explicitly does mean(x[n - pre_avg:n + post_avg]) # with truncation start = n - pre_avg start = start if start > 0 else 0 mov_avg[n] = np.mean(x[start:n + post_avg]) n += 1 # Correct sliding average at the end n = x.shape[0] - post_avg # When post_avg > x.shape[0] (weird case), reset to 0 n = n if n > 0 else 0 while n < x.shape[0]: start = n - pre_avg start = start if start > 0 else 0 mov_avg[n] = np.mean(x[start:n + post_avg]) n += 1 # First mask out all entries not equal to the local max detections = x * (x == mov_max) # Then mask out all entries less than the thresholded average detections = detections * (detections >= (mov_avg + delta)) # Initialize peaks array, to be filled greedily peaks = [] # Remove onsets which are close together in time last_onset = -np.inf for i in np.nonzero(detections)[0]: # Only report an onset if the "wait" samples was reported if i > last_onset + wait: peaks.append(i) # Save last reported onset last_onset = i return np.array(peaks)
python
{ "resource": "" }
q268017
sparsify_rows
test
def sparsify_rows(x, quantile=0.01): ''' Return a row-sparse matrix approximating the input `x`. Parameters ---------- x : np.ndarray [ndim <= 2] The input matrix to sparsify. quantile : float in [0, 1.0) Percentage of magnitude to discard in each row of `x` Returns ------- x_sparse : `scipy.sparse.csr_matrix` [shape=x.shape] Row-sparsified approximation of `x` If `x.ndim == 1`, then `x` is interpreted as a row vector, and `x_sparse.shape == (1, len(x))`. Raises ------ ParameterError If `x.ndim > 2` If `quantile` lies outside `[0, 1.0)` Notes ----- This function caches at level 40. Examples -------- >>> # Construct a Hann window to sparsify >>> x = scipy.signal.hann(32) >>> x array([ 0. , 0.01 , 0.041, 0.09 , 0.156, 0.236, 0.326, 0.424, 0.525, 0.625, 0.72 , 0.806, 0.879, 0.937, 0.977, 0.997, 0.997, 0.977, 0.937, 0.879, 0.806, 0.72 , 0.625, 0.525, 0.424, 0.326, 0.236, 0.156, 0.09 , 0.041, 0.01 , 0. ]) >>> # Discard the bottom percentile >>> x_sparse = librosa.util.sparsify_rows(x, quantile=0.01) >>> x_sparse <1x32 sparse matrix of type '<type 'numpy.float64'>' with 26 stored elements in Compressed Sparse Row format> >>> x_sparse.todense() matrix([[ 0. , 0. , 0. , 0.09 , 0.156, 0.236, 0.326, 0.424, 0.525, 0.625, 0.72 , 0.806, 0.879, 0.937, 0.977, 0.997, 0.997, 0.977, 0.937, 0.879, 0.806, 0.72 , 0.625, 0.525, 0.424, 0.326, 0.236, 0.156, 0.09 , 0. , 0. , 0. ]]) >>> # Discard up to the bottom 10th percentile >>> x_sparse = librosa.util.sparsify_rows(x, quantile=0.1) >>> x_sparse <1x32 sparse matrix of type '<type 'numpy.float64'>' with 20 stored elements in Compressed Sparse Row format> >>> x_sparse.todense() matrix([[ 0. , 0. , 0. , 0. , 0. , 0. , 0.326, 0.424, 0.525, 0.625, 0.72 , 0.806, 0.879, 0.937, 0.977, 0.997, 0.997, 0.977, 0.937, 0.879, 0.806, 0.72 , 0.625, 0.525, 0.424, 0.326, 0. , 0. , 0. , 0. , 0. , 0. ]]) ''' if x.ndim == 1: x = x.reshape((1, -1)) elif x.ndim > 2: raise ParameterError('Input must have 2 or fewer dimensions. ' 'Provided x.shape={}.'.format(x.shape)) if not 0.0 <= quantile < 1: raise ParameterError('Invalid quantile {:.2f}'.format(quantile)) x_sparse = scipy.sparse.lil_matrix(x.shape, dtype=x.dtype) mags = np.abs(x) norms = np.sum(mags, axis=1, keepdims=True) mag_sort = np.sort(mags, axis=1) cumulative_mag = np.cumsum(mag_sort / norms, axis=1) threshold_idx = np.argmin(cumulative_mag < quantile, axis=1) for i, j in enumerate(threshold_idx): idx = np.where(mags[i] >= mag_sort[i, j]) x_sparse[i, idx] = x[i, idx] return x_sparse.tocsr()
python
{ "resource": "" }
q268018
roll_sparse
test
def roll_sparse(x, shift, axis=0): '''Sparse matrix roll This operation is equivalent to ``numpy.roll``, but operates on sparse matrices. Parameters ---------- x : scipy.sparse.spmatrix or np.ndarray The sparse matrix input shift : int The number of positions to roll the specified axis axis : (0, 1, -1) The axis along which to roll. Returns ------- x_rolled : same type as `x` The rolled matrix, with the same format as `x` See Also -------- numpy.roll Examples -------- >>> # Generate a random sparse binary matrix >>> X = scipy.sparse.lil_matrix(np.random.randint(0, 2, size=(5,5))) >>> X_roll = roll_sparse(X, 2, axis=0) # Roll by 2 on the first axis >>> X_dense_r = roll_sparse(X.toarray(), 2, axis=0) # Equivalent dense roll >>> np.allclose(X_roll, X_dense_r.toarray()) True ''' if not scipy.sparse.isspmatrix(x): return np.roll(x, shift, axis=axis) # shift-mod-length lets us have shift > x.shape[axis] if axis not in [0, 1, -1]: raise ParameterError('axis must be one of (0, 1, -1)') shift = np.mod(shift, x.shape[axis]) if shift == 0: return x.copy() fmt = x.format if axis == 0: x = x.tocsc() elif axis in (-1, 1): x = x.tocsr() # lil matrix to start x_r = scipy.sparse.lil_matrix(x.shape, dtype=x.dtype) idx_in = [slice(None)] * x.ndim idx_out = [slice(None)] * x_r.ndim idx_in[axis] = slice(0, -shift) idx_out[axis] = slice(shift, None) x_r[tuple(idx_out)] = x[tuple(idx_in)] idx_out[axis] = slice(0, shift) idx_in[axis] = slice(-shift, None) x_r[tuple(idx_out)] = x[tuple(idx_in)] return x_r.asformat(fmt)
python
{ "resource": "" }
q268019
buf_to_float
test
def buf_to_float(x, n_bytes=2, dtype=np.float32): """Convert an integer buffer to floating point values. This is primarily useful when loading integer-valued wav data into numpy arrays. See Also -------- buf_to_float Parameters ---------- x : np.ndarray [dtype=int] The integer-valued data buffer n_bytes : int [1, 2, 4] The number of bytes per sample in `x` dtype : numeric type The target output type (default: 32-bit float) Returns ------- x_float : np.ndarray [dtype=float] The input data buffer cast to floating point """ # Invert the scale of the data scale = 1./float(1 << ((8 * n_bytes) - 1)) # Construct the format string fmt = '<i{:d}'.format(n_bytes) # Rescale and format the data buffer return scale * np.frombuffer(x, fmt).astype(dtype)
python
{ "resource": "" }
q268020
index_to_slice
test
def index_to_slice(idx, idx_min=None, idx_max=None, step=None, pad=True): '''Generate a slice array from an index array. Parameters ---------- idx : list-like Array of index boundaries idx_min : None or int idx_max : None or int Minimum and maximum allowed indices step : None or int Step size for each slice. If `None`, then the default step of 1 is used. pad : boolean If `True`, pad `idx` to span the range `idx_min:idx_max`. Returns ------- slices : list of slice ``slices[i] = slice(idx[i], idx[i+1], step)`` Additional slice objects may be added at the beginning or end, depending on whether ``pad==True`` and the supplied values for `idx_min` and `idx_max`. See Also -------- fix_frames Examples -------- >>> # Generate slices from spaced indices >>> librosa.util.index_to_slice(np.arange(20, 100, 15)) [slice(20, 35, None), slice(35, 50, None), slice(50, 65, None), slice(65, 80, None), slice(80, 95, None)] >>> # Pad to span the range (0, 100) >>> librosa.util.index_to_slice(np.arange(20, 100, 15), ... idx_min=0, idx_max=100) [slice(0, 20, None), slice(20, 35, None), slice(35, 50, None), slice(50, 65, None), slice(65, 80, None), slice(80, 95, None), slice(95, 100, None)] >>> # Use a step of 5 for each slice >>> librosa.util.index_to_slice(np.arange(20, 100, 15), ... idx_min=0, idx_max=100, step=5) [slice(0, 20, 5), slice(20, 35, 5), slice(35, 50, 5), slice(50, 65, 5), slice(65, 80, 5), slice(80, 95, 5), slice(95, 100, 5)] ''' # First, normalize the index set idx_fixed = fix_frames(idx, idx_min, idx_max, pad=pad) # Now convert the indices to slices return [slice(start, end, step) for (start, end) in zip(idx_fixed, idx_fixed[1:])]
python
{ "resource": "" }
q268021
sync
test
def sync(data, idx, aggregate=None, pad=True, axis=-1): """Synchronous aggregation of a multi-dimensional array between boundaries .. note:: In order to ensure total coverage, boundary points may be added to `idx`. If synchronizing a feature matrix against beat tracker output, ensure that frame index numbers are properly aligned and use the same hop length. Parameters ---------- data : np.ndarray multi-dimensional array of features idx : iterable of ints or slices Either an ordered array of boundary indices, or an iterable collection of slice objects. aggregate : function aggregation function (default: `np.mean`) pad : boolean If `True`, `idx` is padded to span the full range `[0, data.shape[axis]]` axis : int The axis along which to aggregate data Returns ------- data_sync : ndarray `data_sync` will have the same dimension as `data`, except that the `axis` coordinate will be reduced according to `idx`. For example, a 2-dimensional `data` with `axis=-1` should satisfy `data_sync[:, i] = aggregate(data[:, idx[i-1]:idx[i]], axis=-1)` Raises ------ ParameterError If the index set is not of consistent type (all slices or all integers) Notes ----- This function caches at level 40. Examples -------- Beat-synchronous CQT spectra >>> y, sr = librosa.load(librosa.util.example_audio_file()) >>> tempo, beats = librosa.beat.beat_track(y=y, sr=sr, trim=False) >>> C = np.abs(librosa.cqt(y=y, sr=sr)) >>> beats = librosa.util.fix_frames(beats, x_max=C.shape[1]) By default, use mean aggregation >>> C_avg = librosa.util.sync(C, beats) Use median-aggregation instead of mean >>> C_med = librosa.util.sync(C, beats, ... aggregate=np.median) Or sub-beat synchronization >>> sub_beats = librosa.segment.subsegment(C, beats) >>> sub_beats = librosa.util.fix_frames(sub_beats, x_max=C.shape[1]) >>> C_med_sub = librosa.util.sync(C, sub_beats, aggregate=np.median) Plot the results >>> import matplotlib.pyplot as plt >>> beat_t = librosa.frames_to_time(beats, sr=sr) >>> subbeat_t = librosa.frames_to_time(sub_beats, sr=sr) >>> plt.figure() >>> plt.subplot(3, 1, 1) >>> librosa.display.specshow(librosa.amplitude_to_db(C, ... ref=np.max), ... x_axis='time') >>> plt.title('CQT power, shape={}'.format(C.shape)) >>> plt.subplot(3, 1, 2) >>> librosa.display.specshow(librosa.amplitude_to_db(C_med, ... ref=np.max), ... x_coords=beat_t, x_axis='time') >>> plt.title('Beat synchronous CQT power, ' ... 'shape={}'.format(C_med.shape)) >>> plt.subplot(3, 1, 3) >>> librosa.display.specshow(librosa.amplitude_to_db(C_med_sub, ... ref=np.max), ... x_coords=subbeat_t, x_axis='time') >>> plt.title('Sub-beat synchronous CQT power, ' ... 'shape={}'.format(C_med_sub.shape)) >>> plt.tight_layout() """ if aggregate is None: aggregate = np.mean shape = list(data.shape) if np.all([isinstance(_, slice) for _ in idx]): slices = idx elif np.all([np.issubdtype(type(_), np.integer) for _ in idx]): slices = index_to_slice(np.asarray(idx), 0, shape[axis], pad=pad) else: raise ParameterError('Invalid index set: {}'.format(idx)) agg_shape = list(shape) agg_shape[axis] = len(slices) data_agg = np.empty(agg_shape, order='F' if np.isfortran(data) else 'C', dtype=data.dtype) idx_in = [slice(None)] * data.ndim idx_agg = [slice(None)] * data_agg.ndim for (i, segment) in enumerate(slices): idx_in[axis] = segment idx_agg[axis] = i data_agg[tuple(idx_agg)] = aggregate(data[tuple(idx_in)], axis=axis) return data_agg
python
{ "resource": "" }
q268022
softmask
test
def softmask(X, X_ref, power=1, split_zeros=False): '''Robustly compute a softmask operation. `M = X**power / (X**power + X_ref**power)` Parameters ---------- X : np.ndarray The (non-negative) input array corresponding to the positive mask elements X_ref : np.ndarray The (non-negative) array of reference or background elements. Must have the same shape as `X`. power : number > 0 or np.inf If finite, returns the soft mask computed in a numerically stable way If infinite, returns a hard (binary) mask equivalent to `X > X_ref`. Note: for hard masks, ties are always broken in favor of `X_ref` (`mask=0`). split_zeros : bool If `True`, entries where `X` and X`_ref` are both small (close to 0) will receive mask values of 0.5. Otherwise, the mask is set to 0 for these entries. Returns ------- mask : np.ndarray, shape=`X.shape` The output mask array Raises ------ ParameterError If `X` and `X_ref` have different shapes. If `X` or `X_ref` are negative anywhere If `power <= 0` Examples -------- >>> X = 2 * np.ones((3, 3)) >>> X_ref = np.vander(np.arange(3.0)) >>> X array([[ 2., 2., 2.], [ 2., 2., 2.], [ 2., 2., 2.]]) >>> X_ref array([[ 0., 0., 1.], [ 1., 1., 1.], [ 4., 2., 1.]]) >>> librosa.util.softmask(X, X_ref, power=1) array([[ 1. , 1. , 0.667], [ 0.667, 0.667, 0.667], [ 0.333, 0.5 , 0.667]]) >>> librosa.util.softmask(X_ref, X, power=1) array([[ 0. , 0. , 0.333], [ 0.333, 0.333, 0.333], [ 0.667, 0.5 , 0.333]]) >>> librosa.util.softmask(X, X_ref, power=2) array([[ 1. , 1. , 0.8], [ 0.8, 0.8, 0.8], [ 0.2, 0.5, 0.8]]) >>> librosa.util.softmask(X, X_ref, power=4) array([[ 1. , 1. , 0.941], [ 0.941, 0.941, 0.941], [ 0.059, 0.5 , 0.941]]) >>> librosa.util.softmask(X, X_ref, power=100) array([[ 1.000e+00, 1.000e+00, 1.000e+00], [ 1.000e+00, 1.000e+00, 1.000e+00], [ 7.889e-31, 5.000e-01, 1.000e+00]]) >>> librosa.util.softmask(X, X_ref, power=np.inf) array([[ True, True, True], [ True, True, True], [False, False, True]], dtype=bool) ''' if X.shape != X_ref.shape: raise ParameterError('Shape mismatch: {}!={}'.format(X.shape, X_ref.shape)) if np.any(X < 0) or np.any(X_ref < 0): raise ParameterError('X and X_ref must be non-negative') if power <= 0: raise ParameterError('power must be strictly positive') # We're working with ints, cast to float. dtype = X.dtype if not np.issubdtype(dtype, np.floating): dtype = np.float32 # Re-scale the input arrays relative to the larger value Z = np.maximum(X, X_ref).astype(dtype) bad_idx = (Z < np.finfo(dtype).tiny) Z[bad_idx] = 1 # For finite power, compute the softmask if np.isfinite(power): mask = (X / Z)**power ref_mask = (X_ref / Z)**power good_idx = ~bad_idx mask[good_idx] /= mask[good_idx] + ref_mask[good_idx] # Wherever energy is below energy in both inputs, split the mask if split_zeros: mask[bad_idx] = 0.5 else: mask[bad_idx] = 0.0 else: # Otherwise, compute the hard mask mask = X > X_ref return mask
python
{ "resource": "" }
q268023
tiny
test
def tiny(x): '''Compute the tiny-value corresponding to an input's data type. This is the smallest "usable" number representable in `x`'s data type (e.g., float32). This is primarily useful for determining a threshold for numerical underflow in division or multiplication operations. Parameters ---------- x : number or np.ndarray The array to compute the tiny-value for. All that matters here is `x.dtype`. Returns ------- tiny_value : float The smallest positive usable number for the type of `x`. If `x` is integer-typed, then the tiny value for `np.float32` is returned instead. See Also -------- numpy.finfo Examples -------- For a standard double-precision floating point number: >>> librosa.util.tiny(1.0) 2.2250738585072014e-308 Or explicitly as double-precision >>> librosa.util.tiny(np.asarray(1e-5, dtype=np.float64)) 2.2250738585072014e-308 Or complex numbers >>> librosa.util.tiny(1j) 2.2250738585072014e-308 Single-precision floating point: >>> librosa.util.tiny(np.asarray(1e-5, dtype=np.float32)) 1.1754944e-38 Integer >>> librosa.util.tiny(5) 1.1754944e-38 ''' # Make sure we have an array view x = np.asarray(x) # Only floating types generate a tiny if np.issubdtype(x.dtype, np.floating) or np.issubdtype(x.dtype, np.complexfloating): dtype = x.dtype else: dtype = np.float32 return np.finfo(dtype).tiny
python
{ "resource": "" }
q268024
frames2video
test
def frames2video(frame_dir, video_file, fps=30, fourcc='XVID', filename_tmpl='{:06d}.jpg', start=0, end=0, show_progress=True): """Read the frame images from a directory and join them as a video Args: frame_dir (str): The directory containing video frames. video_file (str): Output filename. fps (float): FPS of the output video. fourcc (str): Fourcc of the output video, this should be compatible with the output file type. filename_tmpl (str): Filename template with the index as the variable. start (int): Starting frame index. end (int): Ending frame index. show_progress (bool): Whether to show a progress bar. """ if end == 0: ext = filename_tmpl.split('.')[-1] end = len([name for name in scandir(frame_dir, ext)]) first_file = osp.join(frame_dir, filename_tmpl.format(start)) check_file_exist(first_file, 'The start frame not found: ' + first_file) img = cv2.imread(first_file) height, width = img.shape[:2] resolution = (width, height) vwriter = cv2.VideoWriter(video_file, VideoWriter_fourcc(*fourcc), fps, resolution) def write_frame(file_idx): filename = osp.join(frame_dir, filename_tmpl.format(file_idx)) img = cv2.imread(filename) vwriter.write(img) if show_progress: track_progress(write_frame, range(start, end)) else: for i in range(start, end): filename = osp.join(frame_dir, filename_tmpl.format(i)) img = cv2.imread(filename) vwriter.write(img) vwriter.release()
python
{ "resource": "" }
q268025
VideoReader.read
test
def read(self): """Read the next frame. If the next frame have been decoded before and in the cache, then return it directly, otherwise decode, cache and return it. Returns: ndarray or None: Return the frame if successful, otherwise None. """ # pos = self._position if self._cache: img = self._cache.get(self._position) if img is not None: ret = True else: if self._position != self._get_real_position(): self._set_real_position(self._position) ret, img = self._vcap.read() if ret: self._cache.put(self._position, img) else: ret, img = self._vcap.read() if ret: self._position += 1 return img
python
{ "resource": "" }
q268026
VideoReader.get_frame
test
def get_frame(self, frame_id): """Get frame by index. Args: frame_id (int): Index of the expected frame, 0-based. Returns: ndarray or None: Return the frame if successful, otherwise None. """ if frame_id < 0 or frame_id >= self._frame_cnt: raise IndexError( '"frame_id" must be between 0 and {}'.format(self._frame_cnt - 1)) if frame_id == self._position: return self.read() if self._cache: img = self._cache.get(frame_id) if img is not None: self._position = frame_id + 1 return img self._set_real_position(frame_id) ret, img = self._vcap.read() if ret: if self._cache: self._cache.put(self._position, img) self._position += 1 return img
python
{ "resource": "" }
q268027
VideoReader.cvt2frames
test
def cvt2frames(self, frame_dir, file_start=0, filename_tmpl='{:06d}.jpg', start=0, max_num=0, show_progress=True): """Convert a video to frame images Args: frame_dir (str): Output directory to store all the frame images. file_start (int): Filenames will start from the specified number. filename_tmpl (str): Filename template with the index as the placeholder. start (int): The starting frame index. max_num (int): Maximum number of frames to be written. show_progress (bool): Whether to show a progress bar. """ mkdir_or_exist(frame_dir) if max_num == 0: task_num = self.frame_cnt - start else: task_num = min(self.frame_cnt - start, max_num) if task_num <= 0: raise ValueError('start must be less than total frame number') if start > 0: self._set_real_position(start) def write_frame(file_idx): img = self.read() filename = osp.join(frame_dir, filename_tmpl.format(file_idx)) cv2.imwrite(filename, img) if show_progress: track_progress(write_frame, range(file_start, file_start + task_num)) else: for i in range(task_num): img = self.read() if img is None: break filename = osp.join(frame_dir, filename_tmpl.format(i + file_start)) cv2.imwrite(filename, img)
python
{ "resource": "" }
q268028
track_progress
test
def track_progress(func, tasks, bar_width=50, **kwargs): """Track the progress of tasks execution with a progress bar. Tasks are done with a simple for-loop. Args: func (callable): The function to be applied to each task. tasks (list or tuple[Iterable, int]): A list of tasks or (tasks, total num). bar_width (int): Width of progress bar. Returns: list: The task results. """ if isinstance(tasks, tuple): assert len(tasks) == 2 assert isinstance(tasks[0], collections_abc.Iterable) assert isinstance(tasks[1], int) task_num = tasks[1] tasks = tasks[0] elif isinstance(tasks, collections_abc.Iterable): task_num = len(tasks) else: raise TypeError( '"tasks" must be an iterable object or a (iterator, int) tuple') prog_bar = ProgressBar(task_num, bar_width) results = [] for task in tasks: results.append(func(task, **kwargs)) prog_bar.update() sys.stdout.write('\n') return results
python
{ "resource": "" }
q268029
track_parallel_progress
test
def track_parallel_progress(func, tasks, nproc, initializer=None, initargs=None, bar_width=50, chunksize=1, skip_first=False, keep_order=True): """Track the progress of parallel task execution with a progress bar. The built-in :mod:`multiprocessing` module is used for process pools and tasks are done with :func:`Pool.map` or :func:`Pool.imap_unordered`. Args: func (callable): The function to be applied to each task. tasks (list or tuple[Iterable, int]): A list of tasks or (tasks, total num). nproc (int): Process (worker) number. initializer (None or callable): Refer to :class:`multiprocessing.Pool` for details. initargs (None or tuple): Refer to :class:`multiprocessing.Pool` for details. chunksize (int): Refer to :class:`multiprocessing.Pool` for details. bar_width (int): Width of progress bar. skip_first (bool): Whether to skip the first sample for each worker when estimating fps, since the initialization step may takes longer. keep_order (bool): If True, :func:`Pool.imap` is used, otherwise :func:`Pool.imap_unordered` is used. Returns: list: The task results. """ if isinstance(tasks, tuple): assert len(tasks) == 2 assert isinstance(tasks[0], collections_abc.Iterable) assert isinstance(tasks[1], int) task_num = tasks[1] tasks = tasks[0] elif isinstance(tasks, collections_abc.Iterable): task_num = len(tasks) else: raise TypeError( '"tasks" must be an iterable object or a (iterator, int) tuple') pool = init_pool(nproc, initializer, initargs) start = not skip_first task_num -= nproc * chunksize * int(skip_first) prog_bar = ProgressBar(task_num, bar_width, start) results = [] if keep_order: gen = pool.imap(func, tasks, chunksize) else: gen = pool.imap_unordered(func, tasks, chunksize) for result in gen: results.append(result) if skip_first: if len(results) < nproc * chunksize: continue elif len(results) == nproc * chunksize: prog_bar.start() continue prog_bar.update() sys.stdout.write('\n') pool.close() pool.join() return results
python
{ "resource": "" }
q268030
imflip
test
def imflip(img, direction='horizontal'): """Flip an image horizontally or vertically. Args: img (ndarray): Image to be flipped. direction (str): The flip direction, either "horizontal" or "vertical". Returns: ndarray: The flipped image. """ assert direction in ['horizontal', 'vertical'] if direction == 'horizontal': return np.flip(img, axis=1) else: return np.flip(img, axis=0)
python
{ "resource": "" }
q268031
imrotate
test
def imrotate(img, angle, center=None, scale=1.0, border_value=0, auto_bound=False): """Rotate an image. Args: img (ndarray): Image to be rotated. angle (float): Rotation angle in degrees, positive values mean clockwise rotation. center (tuple): Center of the rotation in the source image, by default it is the center of the image. scale (float): Isotropic scale factor. border_value (int): Border value. auto_bound (bool): Whether to adjust the image size to cover the whole rotated image. Returns: ndarray: The rotated image. """ if center is not None and auto_bound: raise ValueError('`auto_bound` conflicts with `center`') h, w = img.shape[:2] if center is None: center = ((w - 1) * 0.5, (h - 1) * 0.5) assert isinstance(center, tuple) matrix = cv2.getRotationMatrix2D(center, -angle, scale) if auto_bound: cos = np.abs(matrix[0, 0]) sin = np.abs(matrix[0, 1]) new_w = h * sin + w * cos new_h = h * cos + w * sin matrix[0, 2] += (new_w - w) * 0.5 matrix[1, 2] += (new_h - h) * 0.5 w = int(np.round(new_w)) h = int(np.round(new_h)) rotated = cv2.warpAffine(img, matrix, (w, h), borderValue=border_value) return rotated
python
{ "resource": "" }
q268032
bbox_clip
test
def bbox_clip(bboxes, img_shape): """Clip bboxes to fit the image shape. Args: bboxes (ndarray): Shape (..., 4*k) img_shape (tuple): (height, width) of the image. Returns: ndarray: Clipped bboxes. """ assert bboxes.shape[-1] % 4 == 0 clipped_bboxes = np.empty_like(bboxes, dtype=bboxes.dtype) clipped_bboxes[..., 0::2] = np.maximum( np.minimum(bboxes[..., 0::2], img_shape[1] - 1), 0) clipped_bboxes[..., 1::2] = np.maximum( np.minimum(bboxes[..., 1::2], img_shape[0] - 1), 0) return clipped_bboxes
python
{ "resource": "" }
q268033
bbox_scaling
test
def bbox_scaling(bboxes, scale, clip_shape=None): """Scaling bboxes w.r.t the box center. Args: bboxes (ndarray): Shape(..., 4). scale (float): Scaling factor. clip_shape (tuple, optional): If specified, bboxes that exceed the boundary will be clipped according to the given shape (h, w). Returns: ndarray: Scaled bboxes. """ if float(scale) == 1.0: scaled_bboxes = bboxes.copy() else: w = bboxes[..., 2] - bboxes[..., 0] + 1 h = bboxes[..., 3] - bboxes[..., 1] + 1 dw = (w * (scale - 1)) * 0.5 dh = (h * (scale - 1)) * 0.5 scaled_bboxes = bboxes + np.stack((-dw, -dh, dw, dh), axis=-1) if clip_shape is not None: return bbox_clip(scaled_bboxes, clip_shape) else: return scaled_bboxes
python
{ "resource": "" }
q268034
imcrop
test
def imcrop(img, bboxes, scale=1.0, pad_fill=None): """Crop image patches. 3 steps: scale the bboxes -> clip bboxes -> crop and pad. Args: img (ndarray): Image to be cropped. bboxes (ndarray): Shape (k, 4) or (4, ), location of cropped bboxes. scale (float, optional): Scale ratio of bboxes, the default value 1.0 means no padding. pad_fill (number or list): Value to be filled for padding, None for no padding. Returns: list or ndarray: The cropped image patches. """ chn = 1 if img.ndim == 2 else img.shape[2] if pad_fill is not None: if isinstance(pad_fill, (int, float)): pad_fill = [pad_fill for _ in range(chn)] assert len(pad_fill) == chn _bboxes = bboxes[None, ...] if bboxes.ndim == 1 else bboxes scaled_bboxes = bbox_scaling(_bboxes, scale).astype(np.int32) clipped_bbox = bbox_clip(scaled_bboxes, img.shape) patches = [] for i in range(clipped_bbox.shape[0]): x1, y1, x2, y2 = tuple(clipped_bbox[i, :]) if pad_fill is None: patch = img[y1:y2 + 1, x1:x2 + 1, ...] else: _x1, _y1, _x2, _y2 = tuple(scaled_bboxes[i, :]) if chn == 2: patch_shape = (_y2 - _y1 + 1, _x2 - _x1 + 1) else: patch_shape = (_y2 - _y1 + 1, _x2 - _x1 + 1, chn) patch = np.array( pad_fill, dtype=img.dtype) * np.ones( patch_shape, dtype=img.dtype) x_start = 0 if _x1 >= 0 else -_x1 y_start = 0 if _y1 >= 0 else -_y1 w = x2 - x1 + 1 h = y2 - y1 + 1 patch[y_start:y_start + h, x_start:x_start + w, ...] = img[y1:y1 + h, x1:x1 + w, ...] patches.append(patch) if bboxes.ndim == 1: return patches[0] else: return patches
python
{ "resource": "" }
q268035
impad
test
def impad(img, shape, pad_val=0): """Pad an image to a certain shape. Args: img (ndarray): Image to be padded. shape (tuple): Expected padding shape. pad_val (number or sequence): Values to be filled in padding areas. Returns: ndarray: The padded image. """ if not isinstance(pad_val, (int, float)): assert len(pad_val) == img.shape[-1] if len(shape) < len(img.shape): shape = shape + (img.shape[-1], ) assert len(shape) == len(img.shape) for i in range(len(shape) - 1): assert shape[i] >= img.shape[i] pad = np.empty(shape, dtype=img.dtype) pad[...] = pad_val pad[:img.shape[0], :img.shape[1], ...] = img return pad
python
{ "resource": "" }
q268036
impad_to_multiple
test
def impad_to_multiple(img, divisor, pad_val=0): """Pad an image to ensure each edge to be multiple to some number. Args: img (ndarray): Image to be padded. divisor (int): Padded image edges will be multiple to divisor. pad_val (number or sequence): Same as :func:`impad`. Returns: ndarray: The padded image. """ pad_h = int(np.ceil(img.shape[0] / divisor)) * divisor pad_w = int(np.ceil(img.shape[1] / divisor)) * divisor return impad(img, (pad_h, pad_w), pad_val)
python
{ "resource": "" }
q268037
_scale_size
test
def _scale_size(size, scale): """Rescale a size by a ratio. Args: size (tuple): w, h. scale (float): Scaling factor. Returns: tuple[int]: scaled size. """ w, h = size return int(w * float(scale) + 0.5), int(h * float(scale) + 0.5)
python
{ "resource": "" }
q268038
imresize
test
def imresize(img, size, return_scale=False, interpolation='bilinear'): """Resize image to a given size. Args: img (ndarray): The input image. size (tuple): Target (w, h). return_scale (bool): Whether to return `w_scale` and `h_scale`. interpolation (str): Interpolation method, accepted values are "nearest", "bilinear", "bicubic", "area", "lanczos". Returns: tuple or ndarray: (`resized_img`, `w_scale`, `h_scale`) or `resized_img`. """ h, w = img.shape[:2] resized_img = cv2.resize( img, size, interpolation=interp_codes[interpolation]) if not return_scale: return resized_img else: w_scale = size[0] / w h_scale = size[1] / h return resized_img, w_scale, h_scale
python
{ "resource": "" }
q268039
imresize_like
test
def imresize_like(img, dst_img, return_scale=False, interpolation='bilinear'): """Resize image to the same size of a given image. Args: img (ndarray): The input image. dst_img (ndarray): The target image. return_scale (bool): Whether to return `w_scale` and `h_scale`. interpolation (str): Same as :func:`resize`. Returns: tuple or ndarray: (`resized_img`, `w_scale`, `h_scale`) or `resized_img`. """ h, w = dst_img.shape[:2] return imresize(img, (w, h), return_scale, interpolation)
python
{ "resource": "" }
q268040
imrescale
test
def imrescale(img, scale, return_scale=False, interpolation='bilinear'): """Resize image while keeping the aspect ratio. Args: img (ndarray): The input image. scale (float or tuple[int]): The scaling factor or maximum size. If it is a float number, then the image will be rescaled by this factor, else if it is a tuple of 2 integers, then the image will be rescaled as large as possible within the scale. return_scale (bool): Whether to return the scaling factor besides the rescaled image. interpolation (str): Same as :func:`resize`. Returns: ndarray: The rescaled image. """ h, w = img.shape[:2] if isinstance(scale, (float, int)): if scale <= 0: raise ValueError( 'Invalid scale {}, must be positive.'.format(scale)) scale_factor = scale elif isinstance(scale, tuple): max_long_edge = max(scale) max_short_edge = min(scale) scale_factor = min(max_long_edge / max(h, w), max_short_edge / min(h, w)) else: raise TypeError( 'Scale must be a number or tuple of int, but got {}'.format( type(scale))) new_size = _scale_size((w, h), scale_factor) rescaled_img = imresize(img, new_size, interpolation=interpolation) if return_scale: return rescaled_img, scale_factor else: return rescaled_img
python
{ "resource": "" }
q268041
_register_handler
test
def _register_handler(handler, file_formats): """Register a handler for some file extensions. Args: handler (:obj:`BaseFileHandler`): Handler to be registered. file_formats (str or list[str]): File formats to be handled by this handler. """ if not isinstance(handler, BaseFileHandler): raise TypeError( 'handler must be a child of BaseFileHandler, not {}'.format( type(handler))) if isinstance(file_formats, str): file_formats = [file_formats] if not is_list_of(file_formats, str): raise TypeError('file_formats must be a str or a list of str') for ext in file_formats: file_handlers[ext] = handler
python
{ "resource": "" }
q268042
get_priority
test
def get_priority(priority): """Get priority value. Args: priority (int or str or :obj:`Priority`): Priority. Returns: int: The priority value. """ if isinstance(priority, int): if priority < 0 or priority > 100: raise ValueError('priority must be between 0 and 100') return priority elif isinstance(priority, Priority): return priority.value elif isinstance(priority, str): return Priority[priority.upper()].value else: raise TypeError('priority must be an integer or Priority enum value')
python
{ "resource": "" }
q268043
dequantize
test
def dequantize(arr, min_val, max_val, levels, dtype=np.float64): """Dequantize an array. Args: arr (ndarray): Input array. min_val (scalar): Minimum value to be clipped. max_val (scalar): Maximum value to be clipped. levels (int): Quantization levels. dtype (np.type): The type of the dequantized array. Returns: tuple: Dequantized array. """ if not (isinstance(levels, int) and levels > 1): raise ValueError( 'levels must be a positive integer, but got {}'.format(levels)) if min_val >= max_val: raise ValueError( 'min_val ({}) must be smaller than max_val ({})'.format( min_val, max_val)) dequantized_arr = (arr + 0.5).astype(dtype) * ( max_val - min_val) / levels + min_val return dequantized_arr
python
{ "resource": "" }
q268044
imshow
test
def imshow(img, win_name='', wait_time=0): """Show an image. Args: img (str or ndarray): The image to be displayed. win_name (str): The window name. wait_time (int): Value of waitKey param. """ cv2.imshow(win_name, imread(img)) cv2.waitKey(wait_time)
python
{ "resource": "" }
q268045
imshow_bboxes
test
def imshow_bboxes(img, bboxes, colors='green', top_k=-1, thickness=1, show=True, win_name='', wait_time=0, out_file=None): """Draw bboxes on an image. Args: img (str or ndarray): The image to be displayed. bboxes (list or ndarray): A list of ndarray of shape (k, 4). colors (list[str or tuple or Color]): A list of colors. top_k (int): Plot the first k bboxes only if set positive. thickness (int): Thickness of lines. show (bool): Whether to show the image. win_name (str): The window name. wait_time (int): Value of waitKey param. out_file (str, optional): The filename to write the image. """ img = imread(img) if isinstance(bboxes, np.ndarray): bboxes = [bboxes] if not isinstance(colors, list): colors = [colors for _ in range(len(bboxes))] colors = [color_val(c) for c in colors] assert len(bboxes) == len(colors) for i, _bboxes in enumerate(bboxes): _bboxes = _bboxes.astype(np.int32) if top_k <= 0: _top_k = _bboxes.shape[0] else: _top_k = min(top_k, _bboxes.shape[0]) for j in range(_top_k): left_top = (_bboxes[j, 0], _bboxes[j, 1]) right_bottom = (_bboxes[j, 2], _bboxes[j, 3]) cv2.rectangle( img, left_top, right_bottom, colors[i], thickness=thickness) if show: imshow(img, win_name, wait_time) if out_file is not None: imwrite(img, out_file)
python
{ "resource": "" }
q268046
flowread
test
def flowread(flow_or_path, quantize=False, concat_axis=0, *args, **kwargs): """Read an optical flow map. Args: flow_or_path (ndarray or str): A flow map or filepath. quantize (bool): whether to read quantized pair, if set to True, remaining args will be passed to :func:`dequantize_flow`. concat_axis (int): The axis that dx and dy are concatenated, can be either 0 or 1. Ignored if quantize is False. Returns: ndarray: Optical flow represented as a (h, w, 2) numpy array """ if isinstance(flow_or_path, np.ndarray): if (flow_or_path.ndim != 3) or (flow_or_path.shape[-1] != 2): raise ValueError('Invalid flow with shape {}'.format( flow_or_path.shape)) return flow_or_path elif not is_str(flow_or_path): raise TypeError( '"flow_or_path" must be a filename or numpy array, not {}'.format( type(flow_or_path))) if not quantize: with open(flow_or_path, 'rb') as f: try: header = f.read(4).decode('utf-8') except Exception: raise IOError('Invalid flow file: {}'.format(flow_or_path)) else: if header != 'PIEH': raise IOError( 'Invalid flow file: {}, header does not contain PIEH'. format(flow_or_path)) w = np.fromfile(f, np.int32, 1).squeeze() h = np.fromfile(f, np.int32, 1).squeeze() flow = np.fromfile(f, np.float32, w * h * 2).reshape((h, w, 2)) else: assert concat_axis in [0, 1] cat_flow = imread(flow_or_path, flag='unchanged') if cat_flow.ndim != 2: raise IOError( '{} is not a valid quantized flow file, its dimension is {}.'. format(flow_or_path, cat_flow.ndim)) assert cat_flow.shape[concat_axis] % 2 == 0 dx, dy = np.split(cat_flow, 2, axis=concat_axis) flow = dequantize_flow(dx, dy, *args, **kwargs) return flow.astype(np.float32)
python
{ "resource": "" }
q268047
flowwrite
test
def flowwrite(flow, filename, quantize=False, concat_axis=0, *args, **kwargs): """Write optical flow to file. If the flow is not quantized, it will be saved as a .flo file losslessly, otherwise a jpeg image which is lossy but of much smaller size. (dx and dy will be concatenated horizontally into a single image if quantize is True.) Args: flow (ndarray): (h, w, 2) array of optical flow. filename (str): Output filepath. quantize (bool): Whether to quantize the flow and save it to 2 jpeg images. If set to True, remaining args will be passed to :func:`quantize_flow`. concat_axis (int): The axis that dx and dy are concatenated, can be either 0 or 1. Ignored if quantize is False. """ if not quantize: with open(filename, 'wb') as f: f.write('PIEH'.encode('utf-8')) np.array([flow.shape[1], flow.shape[0]], dtype=np.int32).tofile(f) flow = flow.astype(np.float32) flow.tofile(f) f.flush() else: assert concat_axis in [0, 1] dx, dy = quantize_flow(flow, *args, **kwargs) dxdy = np.concatenate((dx, dy), axis=concat_axis) imwrite(dxdy, filename)
python
{ "resource": "" }
q268048
dequantize_flow
test
def dequantize_flow(dx, dy, max_val=0.02, denorm=True): """Recover from quantized flow. Args: dx (ndarray): Quantized dx. dy (ndarray): Quantized dy. max_val (float): Maximum value used when quantizing. denorm (bool): Whether to multiply flow values with width/height. Returns: ndarray: Dequantized flow. """ assert dx.shape == dy.shape assert dx.ndim == 2 or (dx.ndim == 3 and dx.shape[-1] == 1) dx, dy = [dequantize(d, -max_val, max_val, 255) for d in [dx, dy]] if denorm: dx *= dx.shape[1] dy *= dx.shape[0] flow = np.dstack((dx, dy)) return flow
python
{ "resource": "" }
q268049
load_state_dict
test
def load_state_dict(module, state_dict, strict=False, logger=None): """Load state_dict to a module. This method is modified from :meth:`torch.nn.Module.load_state_dict`. Default value for ``strict`` is set to ``False`` and the message for param mismatch will be shown even if strict is False. Args: module (Module): Module that receives the state_dict. state_dict (OrderedDict): Weights. strict (bool): whether to strictly enforce that the keys in :attr:`state_dict` match the keys returned by this module's :meth:`~torch.nn.Module.state_dict` function. Default: ``False``. logger (:obj:`logging.Logger`, optional): Logger to log the error message. If not specified, print function will be used. """ unexpected_keys = [] own_state = module.state_dict() for name, param in state_dict.items(): if name not in own_state: unexpected_keys.append(name) continue if isinstance(param, torch.nn.Parameter): # backwards compatibility for serialized parameters param = param.data try: own_state[name].copy_(param) except Exception: raise RuntimeError('While copying the parameter named {}, ' 'whose dimensions in the model are {} and ' 'whose dimensions in the checkpoint are {}.' .format(name, own_state[name].size(), param.size())) missing_keys = set(own_state.keys()) - set(state_dict.keys()) err_msg = [] if unexpected_keys: err_msg.append('unexpected key in source state_dict: {}\n'.format( ', '.join(unexpected_keys))) if missing_keys: err_msg.append('missing keys in source state_dict: {}\n'.format( ', '.join(missing_keys))) err_msg = '\n'.join(err_msg) if err_msg: if strict: raise RuntimeError(err_msg) elif logger is not None: logger.warn(err_msg) else: print(err_msg)
python
{ "resource": "" }
q268050
load_checkpoint
test
def load_checkpoint(model, filename, map_location=None, strict=False, logger=None): """Load checkpoint from a file or URI. Args: model (Module): Module to load checkpoint. filename (str): Either a filepath or URL or modelzoo://xxxxxxx. map_location (str): Same as :func:`torch.load`. strict (bool): Whether to allow different params for the model and checkpoint. logger (:mod:`logging.Logger` or None): The logger for error message. Returns: dict or OrderedDict: The loaded checkpoint. """ # load checkpoint from modelzoo or file or url if filename.startswith('modelzoo://'): import torchvision model_urls = dict() for _, name, ispkg in pkgutil.walk_packages( torchvision.models.__path__): if not ispkg: _zoo = import_module('torchvision.models.{}'.format(name)) _urls = getattr(_zoo, 'model_urls') model_urls.update(_urls) model_name = filename[11:] checkpoint = model_zoo.load_url(model_urls[model_name]) elif filename.startswith('open-mmlab://'): model_name = filename[13:] checkpoint = model_zoo.load_url(open_mmlab_model_urls[model_name]) elif filename.startswith(('http://', 'https://')): checkpoint = model_zoo.load_url(filename) else: if not osp.isfile(filename): raise IOError('{} is not a checkpoint file'.format(filename)) checkpoint = torch.load(filename, map_location=map_location) # get state_dict from checkpoint if isinstance(checkpoint, OrderedDict): state_dict = checkpoint elif isinstance(checkpoint, dict) and 'state_dict' in checkpoint: state_dict = checkpoint['state_dict'] else: raise RuntimeError( 'No state_dict found in checkpoint file {}'.format(filename)) # strip prefix of state_dict if list(state_dict.keys())[0].startswith('module.'): state_dict = {k[7:]: v for k, v in checkpoint['state_dict'].items()} # load state_dict if hasattr(model, 'module'): load_state_dict(model.module, state_dict, strict, logger) else: load_state_dict(model, state_dict, strict, logger) return checkpoint
python
{ "resource": "" }
q268051
weights_to_cpu
test
def weights_to_cpu(state_dict): """Copy a model state_dict to cpu. Args: state_dict (OrderedDict): Model weights on GPU. Returns: OrderedDict: Model weights on GPU. """ state_dict_cpu = OrderedDict() for key, val in state_dict.items(): state_dict_cpu[key] = val.cpu() return state_dict_cpu
python
{ "resource": "" }
q268052
save_checkpoint
test
def save_checkpoint(model, filename, optimizer=None, meta=None): """Save checkpoint to file. The checkpoint will have 3 fields: ``meta``, ``state_dict`` and ``optimizer``. By default ``meta`` will contain version and time info. Args: model (Module): Module whose params are to be saved. filename (str): Checkpoint filename. optimizer (:obj:`Optimizer`, optional): Optimizer to be saved. meta (dict, optional): Metadata to be saved in checkpoint. """ if meta is None: meta = {} elif not isinstance(meta, dict): raise TypeError('meta must be a dict or None, but got {}'.format( type(meta))) meta.update(mmcv_version=mmcv.__version__, time=time.asctime()) mmcv.mkdir_or_exist(osp.dirname(filename)) if hasattr(model, 'module'): model = model.module checkpoint = { 'meta': meta, 'state_dict': weights_to_cpu(model.state_dict()) } if optimizer is not None: checkpoint['optimizer'] = optimizer.state_dict() torch.save(checkpoint, filename)
python
{ "resource": "" }
q268053
Runner.init_optimizer
test
def init_optimizer(self, optimizer): """Init the optimizer. Args: optimizer (dict or :obj:`~torch.optim.Optimizer`): Either an optimizer object or a dict used for constructing the optimizer. Returns: :obj:`~torch.optim.Optimizer`: An optimizer object. Examples: >>> optimizer = dict(type='SGD', lr=0.01, momentum=0.9) >>> type(runner.init_optimizer(optimizer)) <class 'torch.optim.sgd.SGD'> """ if isinstance(optimizer, dict): optimizer = obj_from_dict( optimizer, torch.optim, dict(params=self.model.parameters())) elif not isinstance(optimizer, torch.optim.Optimizer): raise TypeError( 'optimizer must be either an Optimizer object or a dict, ' 'but got {}'.format(type(optimizer))) return optimizer
python
{ "resource": "" }
q268054
Runner.init_logger
test
def init_logger(self, log_dir=None, level=logging.INFO): """Init the logger. Args: log_dir(str, optional): Log file directory. If not specified, no log file will be used. level (int or str): See the built-in python logging module. Returns: :obj:`~logging.Logger`: Python logger. """ logging.basicConfig( format='%(asctime)s - %(levelname)s - %(message)s', level=level) logger = logging.getLogger(__name__) if log_dir and self.rank == 0: filename = '{}.log'.format(self.timestamp) log_file = osp.join(log_dir, filename) self._add_file_handler(logger, log_file, level=level) return logger
python
{ "resource": "" }
q268055
Runner.current_lr
test
def current_lr(self): """Get current learning rates. Returns: list: Current learning rate of all param groups. """ if self.optimizer is None: raise RuntimeError( 'lr is not applicable because optimizer does not exist.') return [group['lr'] for group in self.optimizer.param_groups]
python
{ "resource": "" }
q268056
Runner.register_hook
test
def register_hook(self, hook, priority='NORMAL'): """Register a hook into the hook list. Args: hook (:obj:`Hook`): The hook to be registered. priority (int or str or :obj:`Priority`): Hook priority. Lower value means higher priority. """ assert isinstance(hook, Hook) if hasattr(hook, 'priority'): raise ValueError('"priority" is a reserved attribute for hooks') priority = get_priority(priority) hook.priority = priority # insert the hook to a sorted list inserted = False for i in range(len(self._hooks) - 1, -1, -1): if priority >= self._hooks[i].priority: self._hooks.insert(i + 1, hook) inserted = True break if not inserted: self._hooks.insert(0, hook)
python
{ "resource": "" }
q268057
Runner.run
test
def run(self, data_loaders, workflow, max_epochs, **kwargs): """Start running. Args: data_loaders (list[:obj:`DataLoader`]): Dataloaders for training and validation. workflow (list[tuple]): A list of (phase, epochs) to specify the running order and epochs. E.g, [('train', 2), ('val', 1)] means running 2 epochs for training and 1 epoch for validation, iteratively. max_epochs (int): Total training epochs. """ assert isinstance(data_loaders, list) assert mmcv.is_list_of(workflow, tuple) assert len(data_loaders) == len(workflow) self._max_epochs = max_epochs work_dir = self.work_dir if self.work_dir is not None else 'NONE' self.logger.info('Start running, host: %s, work_dir: %s', get_host_info(), work_dir) self.logger.info('workflow: %s, max: %d epochs', workflow, max_epochs) self.call_hook('before_run') while self.epoch < max_epochs: for i, flow in enumerate(workflow): mode, epochs = flow if isinstance(mode, str): # self.train() if not hasattr(self, mode): raise ValueError( 'runner has no method named "{}" to run an epoch'. format(mode)) epoch_runner = getattr(self, mode) elif callable(mode): # custom train() epoch_runner = mode else: raise TypeError('mode in workflow must be a str or ' 'callable function, not {}'.format( type(mode))) for _ in range(epochs): if mode == 'train' and self.epoch >= max_epochs: return epoch_runner(data_loaders[i], **kwargs) time.sleep(1) # wait for some hooks like loggers to finish self.call_hook('after_run')
python
{ "resource": "" }
q268058
Runner.register_training_hooks
test
def register_training_hooks(self, lr_config, optimizer_config=None, checkpoint_config=None, log_config=None): """Register default hooks for training. Default hooks include: - LrUpdaterHook - OptimizerStepperHook - CheckpointSaverHook - IterTimerHook - LoggerHook(s) """ if optimizer_config is None: optimizer_config = {} if checkpoint_config is None: checkpoint_config = {} self.register_lr_hooks(lr_config) self.register_hook(self.build_hook(optimizer_config, OptimizerHook)) self.register_hook(self.build_hook(checkpoint_config, CheckpointHook)) self.register_hook(IterTimerHook()) if log_config is not None: self.register_logger_hooks(log_config)
python
{ "resource": "" }
q268059
convert_video
test
def convert_video(in_file, out_file, print_cmd=False, pre_options='', **kwargs): """Convert a video with ffmpeg. This provides a general api to ffmpeg, the executed command is:: `ffmpeg -y <pre_options> -i <in_file> <options> <out_file>` Options(kwargs) are mapped to ffmpeg commands with the following rules: - key=val: "-key val" - key=True: "-key" - key=False: "" Args: in_file (str): Input video filename. out_file (str): Output video filename. pre_options (str): Options appears before "-i <in_file>". print_cmd (bool): Whether to print the final ffmpeg command. """ options = [] for k, v in kwargs.items(): if isinstance(v, bool): if v: options.append('-{}'.format(k)) elif k == 'log_level': assert v in [ 'quiet', 'panic', 'fatal', 'error', 'warning', 'info', 'verbose', 'debug', 'trace' ] options.append('-loglevel {}'.format(v)) else: options.append('-{} {}'.format(k, v)) cmd = 'ffmpeg -y {} -i {} {} {}'.format(pre_options, in_file, ' '.join(options), out_file) if print_cmd: print(cmd) subprocess.call(cmd, shell=True)
python
{ "resource": "" }
q268060
resize_video
test
def resize_video(in_file, out_file, size=None, ratio=None, keep_ar=False, log_level='info', print_cmd=False, **kwargs): """Resize a video. Args: in_file (str): Input video filename. out_file (str): Output video filename. size (tuple): Expected size (w, h), eg, (320, 240) or (320, -1). ratio (tuple or float): Expected resize ratio, (2, 0.5) means (w*2, h*0.5). keep_ar (bool): Whether to keep original aspect ratio. log_level (str): Logging level of ffmpeg. print_cmd (bool): Whether to print the final ffmpeg command. """ if size is None and ratio is None: raise ValueError('expected size or ratio must be specified') elif size is not None and ratio is not None: raise ValueError('size and ratio cannot be specified at the same time') options = {'log_level': log_level} if size: if not keep_ar: options['vf'] = 'scale={}:{}'.format(size[0], size[1]) else: options['vf'] = ('scale=w={}:h={}:force_original_aspect_ratio' '=decrease'.format(size[0], size[1])) else: if not isinstance(ratio, tuple): ratio = (ratio, ratio) options['vf'] = 'scale="trunc(iw*{}):trunc(ih*{})"'.format( ratio[0], ratio[1]) convert_video(in_file, out_file, print_cmd, **options)
python
{ "resource": "" }
q268061
cut_video
test
def cut_video(in_file, out_file, start=None, end=None, vcodec=None, acodec=None, log_level='info', print_cmd=False, **kwargs): """Cut a clip from a video. Args: in_file (str): Input video filename. out_file (str): Output video filename. start (None or float): Start time (in seconds). end (None or float): End time (in seconds). vcodec (None or str): Output video codec, None for unchanged. acodec (None or str): Output audio codec, None for unchanged. log_level (str): Logging level of ffmpeg. print_cmd (bool): Whether to print the final ffmpeg command. """ options = {'log_level': log_level} if vcodec is None: options['vcodec'] = 'copy' if acodec is None: options['acodec'] = 'copy' if start: options['ss'] = start else: start = 0 if end: options['t'] = end - start convert_video(in_file, out_file, print_cmd, **options)
python
{ "resource": "" }
q268062
concat_video
test
def concat_video(video_list, out_file, vcodec=None, acodec=None, log_level='info', print_cmd=False, **kwargs): """Concatenate multiple videos into a single one. Args: video_list (list): A list of video filenames out_file (str): Output video filename vcodec (None or str): Output video codec, None for unchanged acodec (None or str): Output audio codec, None for unchanged log_level (str): Logging level of ffmpeg. print_cmd (bool): Whether to print the final ffmpeg command. """ _, tmp_filename = tempfile.mkstemp(suffix='.txt', text=True) with open(tmp_filename, 'w') as f: for filename in video_list: f.write('file {}\n'.format(osp.abspath(filename))) options = {'log_level': log_level} if vcodec is None: options['vcodec'] = 'copy' if acodec is None: options['acodec'] = 'copy' convert_video( tmp_filename, out_file, print_cmd, pre_options='-f concat -safe 0', **options) os.remove(tmp_filename)
python
{ "resource": "" }
q268063
list_from_file
test
def list_from_file(filename, prefix='', offset=0, max_num=0): """Load a text file and parse the content as a list of strings. Args: filename (str): Filename. prefix (str): The prefix to be inserted to the begining of each item. offset (int): The offset of lines. max_num (int): The maximum number of lines to be read, zeros and negatives mean no limitation. Returns: list[str]: A list of strings. """ cnt = 0 item_list = [] with open(filename, 'r') as f: for _ in range(offset): f.readline() for line in f: if max_num > 0 and cnt >= max_num: break item_list.append(prefix + line.rstrip('\n')) cnt += 1 return item_list
python
{ "resource": "" }
q268064
dict_from_file
test
def dict_from_file(filename, key_type=str): """Load a text file and parse the content as a dict. Each line of the text file will be two or more columns splited by whitespaces or tabs. The first column will be parsed as dict keys, and the following columns will be parsed as dict values. Args: filename(str): Filename. key_type(type): Type of the dict's keys. str is user by default and type conversion will be performed if specified. Returns: dict: The parsed contents. """ mapping = {} with open(filename, 'r') as f: for line in f: items = line.rstrip('\n').split() assert len(items) >= 2 key = key_type(items[0]) val = items[1:] if len(items) > 2 else items[1] mapping[key] = val return mapping
python
{ "resource": "" }
q268065
conv3x3
test
def conv3x3(in_planes, out_planes, dilation=1): "3x3 convolution with padding" return nn.Conv2d( in_planes, out_planes, kernel_size=3, padding=dilation, dilation=dilation)
python
{ "resource": "" }
q268066
obj_from_dict
test
def obj_from_dict(info, parent=None, default_args=None): """Initialize an object from dict. The dict must contain the key "type", which indicates the object type, it can be either a string or type, such as "list" or ``list``. Remaining fields are treated as the arguments for constructing the object. Args: info (dict): Object types and arguments. parent (:class:`module`): Module which may containing expected object classes. default_args (dict, optional): Default arguments for initializing the object. Returns: any type: Object built from the dict. """ assert isinstance(info, dict) and 'type' in info assert isinstance(default_args, dict) or default_args is None args = info.copy() obj_type = args.pop('type') if mmcv.is_str(obj_type): if parent is not None: obj_type = getattr(parent, obj_type) else: obj_type = sys.modules[obj_type] elif not isinstance(obj_type, type): raise TypeError('type must be a str or valid type, but got {}'.format( type(obj_type))) if default_args is not None: for name, value in default_args.items(): args.setdefault(name, value) return obj_type(**args)
python
{ "resource": "" }
q268067
imread
test
def imread(img_or_path, flag='color'): """Read an image. Args: img_or_path (ndarray or str): Either a numpy array or image path. If it is a numpy array (loaded image), then it will be returned as is. flag (str): Flags specifying the color type of a loaded image, candidates are `color`, `grayscale` and `unchanged`. Returns: ndarray: Loaded image array. """ if isinstance(img_or_path, np.ndarray): return img_or_path elif is_str(img_or_path): flag = imread_flags[flag] if is_str(flag) else flag check_file_exist(img_or_path, 'img file does not exist: {}'.format(img_or_path)) return cv2.imread(img_or_path, flag) else: raise TypeError('"img" must be a numpy array or a filename')
python
{ "resource": "" }
q268068
imfrombytes
test
def imfrombytes(content, flag='color'): """Read an image from bytes. Args: content (bytes): Image bytes got from files or other streams. flag (str): Same as :func:`imread`. Returns: ndarray: Loaded image array. """ img_np = np.frombuffer(content, np.uint8) flag = imread_flags[flag] if is_str(flag) else flag img = cv2.imdecode(img_np, flag) return img
python
{ "resource": "" }
q268069
imwrite
test
def imwrite(img, file_path, params=None, auto_mkdir=True): """Write image to file Args: img (ndarray): Image array to be written. file_path (str): Image file path. params (None or list): Same as opencv's :func:`imwrite` interface. auto_mkdir (bool): If the parent folder of `file_path` does not exist, whether to create it automatically. Returns: bool: Successful or not. """ if auto_mkdir: dir_name = osp.abspath(osp.dirname(file_path)) mkdir_or_exist(dir_name) return cv2.imwrite(file_path, img, params)
python
{ "resource": "" }
q268070
bgr2gray
test
def bgr2gray(img, keepdim=False): """Convert a BGR image to grayscale image. Args: img (ndarray): The input image. keepdim (bool): If False (by default), then return the grayscale image with 2 dims, otherwise 3 dims. Returns: ndarray: The converted grayscale image. """ out_img = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY) if keepdim: out_img = out_img[..., None] return out_img
python
{ "resource": "" }
q268071
gray2bgr
test
def gray2bgr(img): """Convert a grayscale image to BGR image. Args: img (ndarray or str): The input image. Returns: ndarray: The converted BGR image. """ img = img[..., None] if img.ndim == 2 else img out_img = cv2.cvtColor(img, cv2.COLOR_GRAY2BGR) return out_img
python
{ "resource": "" }
q268072
iter_cast
test
def iter_cast(inputs, dst_type, return_type=None): """Cast elements of an iterable object into some type. Args: inputs (Iterable): The input object. dst_type (type): Destination type. return_type (type, optional): If specified, the output object will be converted to this type, otherwise an iterator. Returns: iterator or specified type: The converted object. """ if not isinstance(inputs, collections_abc.Iterable): raise TypeError('inputs must be an iterable object') if not isinstance(dst_type, type): raise TypeError('"dst_type" must be a valid type') out_iterable = six.moves.map(dst_type, inputs) if return_type is None: return out_iterable else: return return_type(out_iterable)
python
{ "resource": "" }
q268073
is_seq_of
test
def is_seq_of(seq, expected_type, seq_type=None): """Check whether it is a sequence of some type. Args: seq (Sequence): The sequence to be checked. expected_type (type): Expected type of sequence items. seq_type (type, optional): Expected sequence type. Returns: bool: Whether the sequence is valid. """ if seq_type is None: exp_seq_type = collections_abc.Sequence else: assert isinstance(seq_type, type) exp_seq_type = seq_type if not isinstance(seq, exp_seq_type): return False for item in seq: if not isinstance(item, expected_type): return False return True
python
{ "resource": "" }
q268074
slice_list
test
def slice_list(in_list, lens): """Slice a list into several sub lists by a list of given length. Args: in_list (list): The list to be sliced. lens(int or list): The expected length of each out list. Returns: list: A list of sliced list. """ if not isinstance(lens, list): raise TypeError('"indices" must be a list of integers') elif sum(lens) != len(in_list): raise ValueError( 'sum of lens and list length does not match: {} != {}'.format( sum(lens), len(in_list))) out_list = [] idx = 0 for i in range(len(lens)): out_list.append(in_list[idx:idx + lens[i]]) idx += lens[i] return out_list
python
{ "resource": "" }
q268075
check_prerequisites
test
def check_prerequisites( prerequisites, checker, msg_tmpl='Prerequisites "{}" are required in method "{}" but not ' 'found, please install them first.'): """A decorator factory to check if prerequisites are satisfied. Args: prerequisites (str of list[str]): Prerequisites to be checked. checker (callable): The checker method that returns True if a prerequisite is meet, False otherwise. msg_tmpl (str): The message template with two variables. Returns: decorator: A specific decorator. """ def wrap(func): @functools.wraps(func) def wrapped_func(*args, **kwargs): requirements = [prerequisites] if isinstance( prerequisites, str) else prerequisites missing = [] for item in requirements: if not checker(item): missing.append(item) if missing: print(msg_tmpl.format(', '.join(missing), func.__name__)) raise RuntimeError('Prerequisites not meet.') else: return func(*args, **kwargs) return wrapped_func return wrap
python
{ "resource": "" }
q268076
LogBuffer.average
test
def average(self, n=0): """Average latest n values or all values""" assert n >= 0 for key in self.val_history: values = np.array(self.val_history[key][-n:]) nums = np.array(self.n_history[key][-n:]) avg = np.sum(values * nums) / np.sum(nums) self.output[key] = avg self.ready = True
python
{ "resource": "" }
q268077
scatter
test
def scatter(input, devices, streams=None): """Scatters tensor across multiple GPUs. """ if streams is None: streams = [None] * len(devices) if isinstance(input, list): chunk_size = (len(input) - 1) // len(devices) + 1 outputs = [ scatter(input[i], [devices[i // chunk_size]], [streams[i // chunk_size]]) for i in range(len(input)) ] return outputs elif isinstance(input, torch.Tensor): output = input.contiguous() # TODO: copy to a pinned buffer first (if copying from CPU) stream = streams[0] if output.numel() > 0 else None with torch.cuda.device(devices[0]), torch.cuda.stream(stream): output = output.cuda(devices[0], non_blocking=True) return output else: raise Exception('Unknown type {}.'.format(type(input)))
python
{ "resource": "" }
q268078
color_val
test
def color_val(color): """Convert various input to color tuples. Args: color (:obj:`Color`/str/tuple/int/ndarray): Color inputs Returns: tuple[int]: A tuple of 3 integers indicating BGR channels. """ if is_str(color): return Color[color].value elif isinstance(color, Color): return color.value elif isinstance(color, tuple): assert len(color) == 3 for channel in color: assert channel >= 0 and channel <= 255 return color elif isinstance(color, int): assert color >= 0 and color <= 255 return color, color, color elif isinstance(color, np.ndarray): assert color.ndim == 1 and color.size == 3 assert np.all((color >= 0) & (color <= 255)) color = color.astype(np.uint8) return tuple(color) else: raise TypeError('Invalid type for color: {}'.format(type(color)))
python
{ "resource": "" }
q268079
check_time
test
def check_time(timer_id): """Add check points in a single line. This method is suitable for running a task on a list of items. A timer will be registered when the method is called for the first time. :Example: >>> import time >>> import mmcv >>> for i in range(1, 6): >>> # simulate a code block >>> time.sleep(i) >>> mmcv.check_time('task1') 2.000 3.000 4.000 5.000 Args: timer_id (str): Timer identifier. """ if timer_id not in _g_timers: _g_timers[timer_id] = Timer() return 0 else: return _g_timers[timer_id].since_last_check()
python
{ "resource": "" }
q268080
Timer.start
test
def start(self): """Start the timer.""" if not self._is_running: self._t_start = time() self._is_running = True self._t_last = time()
python
{ "resource": "" }
q268081
Timer.since_start
test
def since_start(self): """Total time since the timer is started. Returns (float): Time in seconds. """ if not self._is_running: raise TimerError('timer is not running') self._t_last = time() return self._t_last - self._t_start
python
{ "resource": "" }
q268082
Timer.since_last_check
test
def since_last_check(self): """Time since the last checking. Either :func:`since_start` or :func:`since_last_check` is a checking operation. Returns (float): Time in seconds. """ if not self._is_running: raise TimerError('timer is not running') dur = time() - self._t_last self._t_last = time() return dur
python
{ "resource": "" }
q268083
flowshow
test
def flowshow(flow, win_name='', wait_time=0): """Show optical flow. Args: flow (ndarray or str): The optical flow to be displayed. win_name (str): The window name. wait_time (int): Value of waitKey param. """ flow = flowread(flow) flow_img = flow2rgb(flow) imshow(rgb2bgr(flow_img), win_name, wait_time)
python
{ "resource": "" }
q268084
flow2rgb
test
def flow2rgb(flow, color_wheel=None, unknown_thr=1e6): """Convert flow map to RGB image. Args: flow (ndarray): Array of optical flow. color_wheel (ndarray or None): Color wheel used to map flow field to RGB colorspace. Default color wheel will be used if not specified. unknown_thr (str): Values above this threshold will be marked as unknown and thus ignored. Returns: ndarray: RGB image that can be visualized. """ assert flow.ndim == 3 and flow.shape[-1] == 2 if color_wheel is None: color_wheel = make_color_wheel() assert color_wheel.ndim == 2 and color_wheel.shape[1] == 3 num_bins = color_wheel.shape[0] dx = flow[:, :, 0].copy() dy = flow[:, :, 1].copy() ignore_inds = (np.isnan(dx) | np.isnan(dy) | (np.abs(dx) > unknown_thr) | (np.abs(dy) > unknown_thr)) dx[ignore_inds] = 0 dy[ignore_inds] = 0 rad = np.sqrt(dx**2 + dy**2) if np.any(rad > np.finfo(float).eps): max_rad = np.max(rad) dx /= max_rad dy /= max_rad [h, w] = dx.shape rad = np.sqrt(dx**2 + dy**2) angle = np.arctan2(-dy, -dx) / np.pi bin_real = (angle + 1) / 2 * (num_bins - 1) bin_left = np.floor(bin_real).astype(int) bin_right = (bin_left + 1) % num_bins w = (bin_real - bin_left.astype(np.float32))[..., None] flow_img = ( 1 - w) * color_wheel[bin_left, :] + w * color_wheel[bin_right, :] small_ind = rad <= 1 flow_img[small_ind] = 1 - rad[small_ind, None] * (1 - flow_img[small_ind]) flow_img[np.logical_not(small_ind)] *= 0.75 flow_img[ignore_inds, :] = 0 return flow_img
python
{ "resource": "" }
q268085
make_color_wheel
test
def make_color_wheel(bins=None): """Build a color wheel. Args: bins(list or tuple, optional): Specify the number of bins for each color range, corresponding to six ranges: red -> yellow, yellow -> green, green -> cyan, cyan -> blue, blue -> magenta, magenta -> red. [15, 6, 4, 11, 13, 6] is used for default (see Middlebury). Returns: ndarray: Color wheel of shape (total_bins, 3). """ if bins is None: bins = [15, 6, 4, 11, 13, 6] assert len(bins) == 6 RY, YG, GC, CB, BM, MR = tuple(bins) ry = [1, np.arange(RY) / RY, 0] yg = [1 - np.arange(YG) / YG, 1, 0] gc = [0, 1, np.arange(GC) / GC] cb = [0, 1 - np.arange(CB) / CB, 1] bm = [np.arange(BM) / BM, 0, 1] mr = [1, 0, 1 - np.arange(MR) / MR] num_bins = RY + YG + GC + CB + BM + MR color_wheel = np.zeros((3, num_bins), dtype=np.float32) col = 0 for i, color in enumerate([ry, yg, gc, cb, bm, mr]): for j in range(3): color_wheel[j, col:col + bins[i]] = color[j] col += bins[i] return color_wheel.T
python
{ "resource": "" }
q268086
accuracy
test
def accuracy(output, target, topk=(1, )): """Computes the precision@k for the specified values of k""" with torch.no_grad(): maxk = max(topk) batch_size = target.size(0) _, pred = output.topk(maxk, 1, True, True) pred = pred.t() correct = pred.eq(target.view(1, -1).expand_as(pred)) res = [] for k in topk: correct_k = correct[:k].view(-1).float().sum(0, keepdim=True) res.append(correct_k.mul_(100.0 / batch_size)) return res
python
{ "resource": "" }
q268087
scatter
test
def scatter(inputs, target_gpus, dim=0): """Scatter inputs to target gpus. The only difference from original :func:`scatter` is to add support for :type:`~mmcv.parallel.DataContainer`. """ def scatter_map(obj): if isinstance(obj, torch.Tensor): return OrigScatter.apply(target_gpus, None, dim, obj) if isinstance(obj, DataContainer): if obj.cpu_only: return obj.data else: return Scatter.forward(target_gpus, obj.data) if isinstance(obj, tuple) and len(obj) > 0: return list(zip(*map(scatter_map, obj))) if isinstance(obj, list) and len(obj) > 0: out = list(map(list, zip(*map(scatter_map, obj)))) return out if isinstance(obj, dict) and len(obj) > 0: out = list(map(type(obj), zip(*map(scatter_map, obj.items())))) return out return [obj for targets in target_gpus] # After scatter_map is called, a scatter_map cell will exist. This cell # has a reference to the actual function scatter_map, which has references # to a closure that has a reference to the scatter_map cell (because the # fn is recursive). To avoid this reference cycle, we set the function to # None, clearing the cell try: return scatter_map(inputs) finally: scatter_map = None
python
{ "resource": "" }
q268088
scatter_kwargs
test
def scatter_kwargs(inputs, kwargs, target_gpus, dim=0): """Scatter with support for kwargs dictionary""" inputs = scatter(inputs, target_gpus, dim) if inputs else [] kwargs = scatter(kwargs, target_gpus, dim) if kwargs else [] if len(inputs) < len(kwargs): inputs.extend([() for _ in range(len(kwargs) - len(inputs))]) elif len(kwargs) < len(inputs): kwargs.extend([{} for _ in range(len(inputs) - len(kwargs))]) inputs = tuple(inputs) kwargs = tuple(kwargs) return inputs, kwargs
python
{ "resource": "" }
q268089
Request.fetch
test
async def fetch(self) -> Response: """Fetch all the information by using aiohttp""" if self.request_config.get('DELAY', 0) > 0: await asyncio.sleep(self.request_config['DELAY']) timeout = self.request_config.get('TIMEOUT', 10) try: async with async_timeout.timeout(timeout): resp = await self._make_request() try: resp_data = await resp.text(encoding=self.encoding) except UnicodeDecodeError: resp_data = await resp.read() response = Response( url=self.url, method=self.method, encoding=resp.get_encoding(), html=resp_data, metadata=self.metadata, cookies=resp.cookies, headers=resp.headers, history=resp.history, status=resp.status, aws_json=resp.json, aws_text=resp.text, aws_read=resp.read) # Retry middleware aws_valid_response = self.request_config.get('VALID') if aws_valid_response and iscoroutinefunction(aws_valid_response): response = await aws_valid_response(response) if response.ok: return response else: return await self._retry(error_msg='request url failed!') except asyncio.TimeoutError: return await self._retry(error_msg='timeout') except Exception as e: return await self._retry(error_msg=e) finally: # Close client session await self._close_request_session()
python
{ "resource": "" }
q268090
Response.json
test
async def json(self, *, encoding: str = None, loads: JSONDecoder = DEFAULT_JSON_DECODER, content_type: Optional[str] = 'application/json') -> Any: """Read and decodes JSON response.""" return await self._aws_json( encoding=encoding, loads=loads, content_type=content_type)
python
{ "resource": "" }
q268091
Response.text
test
async def text(self, *, encoding: Optional[str] = None, errors: str = 'strict') -> str: """Read response payload and decode.""" return await self._aws_text(encoding=encoding, errors=errors)
python
{ "resource": "" }
q268092
Spider.handle_callback
test
async def handle_callback(self, aws_callback: typing.Coroutine, response): """Process coroutine callback function""" callback_result = None try: callback_result = await aws_callback except NothingMatchedError as e: self.logger.error(f'<Item: {str(e).lower()}>') except Exception as e: self.logger.error(f'<Callback[{aws_callback.__name__}]: {e}') return callback_result, response
python
{ "resource": "" }
q268093
Spider.multiple_request
test
async def multiple_request(self, urls, is_gather=False, **kwargs): """For crawling multiple urls""" if is_gather: resp_results = await asyncio.gather( *[ self.handle_request(self.request(url=url, **kwargs)) for url in urls ], return_exceptions=True) for index, task_result in enumerate(resp_results): if not isinstance(task_result, RuntimeError) and task_result: _, response = task_result response.index = index yield response else: for index, url in enumerate(urls): _, response = await self.handle_request( self.request(url=url, **kwargs)) response.index = index yield response
python
{ "resource": "" }
q268094
Spider.request
test
def request(self, url: str, method: str = 'GET', *, callback=None, encoding: typing.Optional[str] = None, headers: dict = None, metadata: dict = None, request_config: dict = None, request_session=None, **kwargs): """Init a Request class for crawling html""" headers = headers or {} metadata = metadata or {} request_config = request_config or {} request_session = request_session or self.request_session headers.update(self.headers.copy()) request_config.update(self.request_config.copy()) kwargs.update(self.kwargs.copy()) return Request( url=url, method=method, callback=callback, encoding=encoding, headers=headers, metadata=metadata, request_config=request_config, request_session=request_session, **kwargs)
python
{ "resource": "" }
q268095
Spider.start_master
test
async def start_master(self): """Actually start crawling.""" for url in self.start_urls: request_ins = self.request( url=url, callback=self.parse, metadata=self.metadata) self.request_queue.put_nowait(self.handle_request(request_ins)) workers = [ asyncio.ensure_future(self.start_worker()) for i in range(self.worker_numbers) ] for worker in workers: self.logger.info(f"Worker started: {id(worker)}") await self.request_queue.join() if not self.is_async_start: await self.stop(SIGINT) else: await self._cancel_tasks()
python
{ "resource": "" }
q268096
normalize_task_v2
test
def normalize_task_v2(task): '''Ensures tasks have an action key and strings are converted to python objects''' result = dict() mod_arg_parser = ModuleArgsParser(task) try: action, arguments, result['delegate_to'] = mod_arg_parser.parse() except AnsibleParserError as e: try: task_info = "%s:%s" % (task[FILENAME_KEY], task[LINE_NUMBER_KEY]) del task[FILENAME_KEY] del task[LINE_NUMBER_KEY] except KeyError: task_info = "Unknown" try: import pprint pp = pprint.PrettyPrinter(indent=2) task_pprint = pp.pformat(task) except ImportError: task_pprint = task raise SystemExit("Couldn't parse task at %s (%s)\n%s" % (task_info, e.message, task_pprint)) # denormalize shell -> command conversion if '_uses_shell' in arguments: action = 'shell' del(arguments['_uses_shell']) for (k, v) in list(task.items()): if k in ('action', 'local_action', 'args', 'delegate_to') or k == action: # we don't want to re-assign these values, which were # determined by the ModuleArgsParser() above continue else: result[k] = v result['action'] = dict(__ansible_module__=action) if '_raw_params' in arguments: result['action']['__ansible_arguments__'] = arguments['_raw_params'].split(' ') del(arguments['_raw_params']) else: result['action']['__ansible_arguments__'] = list() if 'argv' in arguments and not result['action']['__ansible_arguments__']: result['action']['__ansible_arguments__'] = arguments['argv'] del(arguments['argv']) result['action'].update(arguments) return result
python
{ "resource": "" }
q268097
parse_yaml_linenumbers
test
def parse_yaml_linenumbers(data, filename): """Parses yaml as ansible.utils.parse_yaml but with linenumbers. The line numbers are stored in each node's LINE_NUMBER_KEY key. """ def compose_node(parent, index): # the line number where the previous token has ended (plus empty lines) line = loader.line node = Composer.compose_node(loader, parent, index) node.__line__ = line + 1 return node def construct_mapping(node, deep=False): if ANSIBLE_VERSION < 2: mapping = Constructor.construct_mapping(loader, node, deep=deep) else: mapping = AnsibleConstructor.construct_mapping(loader, node, deep=deep) if hasattr(node, '__line__'): mapping[LINE_NUMBER_KEY] = node.__line__ else: mapping[LINE_NUMBER_KEY] = mapping._line_number mapping[FILENAME_KEY] = filename return mapping try: if ANSIBLE_VERSION < 2: loader = yaml.Loader(data) else: import inspect kwargs = {} if 'vault_password' in inspect.getargspec(AnsibleLoader.__init__).args: kwargs['vault_password'] = DEFAULT_VAULT_PASSWORD loader = AnsibleLoader(data, **kwargs) loader.compose_node = compose_node loader.construct_mapping = construct_mapping data = loader.get_single_data() except (yaml.parser.ParserError, yaml.scanner.ScannerError) as e: raise SystemExit("Failed to parse YAML in %s: %s" % (filename, str(e))) return data
python
{ "resource": "" }
q268098
bdist_wheel.wheel_dist_name
test
def wheel_dist_name(self): """Return distribution full name with - replaced with _""" return '-'.join((safer_name(self.distribution.get_name()), safer_version(self.distribution.get_version())))
python
{ "resource": "" }
q268099
bdist_wheel.get_archive_basename
test
def get_archive_basename(self): """Return archive name without extension""" impl_tag, abi_tag, plat_tag = self.get_tag() archive_basename = "%s-%s-%s-%s" % ( self.wheel_dist_name, impl_tag, abi_tag, plat_tag) return archive_basename
python
{ "resource": "" }