librosa.util.fix_frames

librosa.util.fix_frames(frames, x_min=0, x_max=None, pad=True)

Fix a list of frames to lie within [x_min, x_max]

Parameters:

frames : np.ndarray [shape=(n_frames,)]

List of non-negative frame indices

x_min : int >= 0 or None

Minimum allowed frame index

x_max : int >= 0 or None

Maximum allowed frame index

pad : boolean

If True, then frames is expanded to span the full range [x_min, x_max]

Returns:

fixed_frames : np.ndarray [shape=(n_fixed_frames,), dtype=int]

Fixed frame indices, flattened and sorted

Raises:

ParameterError

If frames contains negative values

Examples

>>> # Generate a list of frame indices
>>> frames = np.arange(0, 1000.0, 50)
>>> frames
array([   0.,   50.,  100.,  150.,  200.,  250.,  300.,  350.,
        400.,  450.,  500.,  550.,  600.,  650.,  700.,  750.,
        800.,  850.,  900.,  950.])
>>> # Clip to span at most 250
>>> librosa.util.fix_frames(frames, x_max=250)
array([  0,  50, 100, 150, 200, 250])
>>> # Or pad to span up to 2500
>>> librosa.util.fix_frames(frames, x_max=2500)
array([   0,   50,  100,  150,  200,  250,  300,  350,  400,
        450,  500,  550,  600,  650,  700,  750,  800,  850,
        900,  950, 2500])
>>> librosa.util.fix_frames(frames, x_max=2500, pad=False)
array([  0,  50, 100, 150, 200, 250, 300, 350, 400, 450, 500,
       550, 600, 650, 700, 750, 800, 850, 900, 950])

>>> # Or starting away from zero
>>> frames = np.arange(200, 500, 33)
>>> frames
array([200, 233, 266, 299, 332, 365, 398, 431, 464, 497])
>>> librosa.util.fix_frames(frames)
array([  0, 200, 233, 266, 299, 332, 365, 398, 431, 464, 497])
>>> librosa.util.fix_frames(frames, x_max=500)
array([  0, 200, 233, 266, 299, 332, 365, 398, 431, 464, 497,
       500])