| 1 | from moviepy import Clip, ColorClip, CompositeVideoClip, vfx |
| 2 | |
| 3 | |
| 4 | # FadeIn |
| 5 | def fadein_transition(clip: Clip, t: float) -> Clip: |
| 6 | return clip.with_effects([vfx.FadeIn(t)]) |
| 7 | |
| 8 | |
| 9 | # FadeOut |
| 10 | def fadeout_transition(clip: Clip, t: float) -> Clip: |
| 11 | return clip.with_effects([vfx.FadeOut(t)]) |
| 12 | |
| 13 | |
| 14 | # SlideIn |
| 15 | def slidein_transition(clip: Clip, t: float, side: str) -> Clip: |
| 16 | width, height = clip.size |
| 17 | |
| 18 | # MoviePy 内置 SlideIn 在当前这条处理链里对全屏素材不稳定， |
| 19 | # 会出现“逻辑上应用了转场，但画面几乎看不出变化”的情况。 |
| 20 | # 这里改成显式黑底 + 位移动画，保证转场效果可见且行为可控。 |
| 21 | def position(current_time: float): |
| 22 | progress = min(max(current_time / max(t, 0.001), 0), 1) |
| 23 | |
| 24 | if side == "left": |
| 25 | return (-width + width * progress, 0) |
| 26 | if side == "right": |
| 27 | return (width - width * progress, 0) |
| 28 | if side == "top": |
| 29 | return (0, -height + height * progress) |
| 30 | if side == "bottom": |
| 31 | return (0, height - height * progress) |
| 32 | return (0, 0) |
| 33 | |
| 34 | background = ColorClip(size=(width, height), color=(0, 0, 0)).with_duration( |
| 35 | clip.duration |
| 36 | ) |
| 37 | moving_clip = clip.with_position(position) |
| 38 | return CompositeVideoClip([background, moving_clip], size=(width, height)).with_duration( |
| 39 | clip.duration |
| 40 | ) |
| 41 | |
| 42 | |
| 43 | # SlideOut |
| 44 | def slideout_transition(clip: Clip, t: float, side: str) -> Clip: |
| 45 | width, height = clip.size |
| 46 | transition_start = max(clip.duration - t, 0) |
| 47 | |
| 48 | # SlideOut 同样改成显式位移，保证片段末尾能稳定滑出画面。 |
| 49 | def position(current_time: float): |
| 50 | if current_time <= transition_start: |
| 51 | return (0, 0) |
| 52 | |
| 53 | progress = min( |
| 54 | max((current_time - transition_start) / max(t, 0.001), 0), 1 |
| 55 | ) |
| 56 | |
| 57 | if side == "left": |
| 58 | return (-width * progress, 0) |
| 59 | if side == "right": |
| 60 | return (width * progress, 0) |
| 61 | if side == "top": |
| 62 | return (0, -height * progress) |
| 63 | if side == "bottom": |
| 64 | return (0, height * progress) |
| 65 | return (0, 0) |
| 66 | |
| 67 | background = ColorClip(size=(width, height), color=(0, 0, 0)).with_duration( |
| 68 | clip.duration |
| 69 | ) |
| 70 | moving_clip = clip.with_position(position) |
| 71 | return CompositeVideoClip([background, moving_clip], size=(width, height)).with_duration( |
| 72 | clip.duration |
| 73 | ) |
| 74 |