22 lines
632 B
Python
22 lines
632 B
Python
import numpy as np
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from moviepy.decorators import audio_video_fx
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@audio_video_fx
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def audio_fadein(clip, duration):
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""" Return an audio (or video) clip that is first mute, then the
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sound arrives progressively over ``duration`` seconds. """
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def fading(gf,t):
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gft = gf(t)
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if np.isscalar(t):
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factor = min(1.0 * t / duration, 1)
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factor = np.array([factor,factor])
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else:
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factor = np.minimum(1.0 * t / duration, 1)
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factor = np.vstack([factor,factor]).T
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return factor * gft
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return clip.fl(fading, keep_duration = True)
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