[timecode] Add new Timecode and Framerate types

The existing FrameTimecode type assumes fixed framerate, and relies on it for calculation of durations.

This splits both out, and adds timing information in addition to frame number.

This will need to be integrated in the VideoStream side of things first, before starting to work through SceneManager and the Detector interface.

Author: Breakthrough

scenedetect/timecode.py

@@ -0,0 +1,35 @@
+#
+#            PySceneDetect: Python-Based Video Scene Detector
+#   -------------------------------------------------------------------
+#     [  Site:    https://scenedetect.com                           ]
+#     [  Docs:    https://scenedetect.com/docs/                     ]
+#     [  Github:  https://github.com/Breakthrough/PySceneDetect/    ]
+#
+# Copyright (C) 2014-2025 Brandon Castellano <http://www.bcastell.com>.
+# PySceneDetect is licensed under the BSD 3-Clause License; see the
+# included LICENSE file, or visit one of the above pages for details.
+#
+
+from dataclasses import dataclass
+
+
+@dataclass
+class Framerate:
+    """Describes how time passes between frames in the video."""
+
+    rate: float
+    """Framerate in frames per second."""
+    fixed: bool
+    """True for constant frame rate (CFR), false for variable frame rate (VFR)."""
+
+
+@dataclass
+class Timecode:
+    """Timing information associated with a given frame."""
+
+    time: float
+    """Presentation time in seconds."""
+    duration: float
+    """Presentation duration in seconds."""
+    frame: int
+    """Frame number."""