initial commit and version 1.0

moviepy/video/fx/CrossFadeIn.py

@@ -0,0 +1,27 @@
+from dataclasses import dataclass
+
+from moviepy.Clip import Clip
+from moviepy.Effect import Effect
+from moviepy.video.fx.FadeIn import FadeIn
+
+
+@dataclass
+class CrossFadeIn(Effect):
+    """Makes the clip appear progressively, over ``duration`` seconds.
+    Only works when the clip is included in a CompositeVideoClip.
+    """
+
+    duration: float
+
+    def apply(self, clip: Clip) -> Clip:
+        """Apply the effect to the clip."""
+        if clip.duration is None:
+            raise ValueError("Attribute 'duration' not set")
+
+        if clip.mask is None:
+            clip = clip.with_mask()
+
+        clip.mask.duration = clip.duration
+        clip.mask = clip.mask.with_effects([FadeIn(self.duration)])
+
+        return clip