Function test_api_device_callback

tests/test_api.py:137–158

Demonstrate how to use a webcam/device/pipe and a callback function. Instead of calling `open_video()`, an existing `cv2.VideoCapture` can be used by wrapping it with a `VideoCaptureAdapter.`

(test_video_file: str)

def test_api_device_callback(test_video_file: str):
    """Demonstrate how to use a webcam/device/pipe and a callback function.
    Instead of calling `open_video()`, an existing `cv2.VideoCapture` can be used by
    wrapping it with a `VideoCaptureAdapter.`"""
    import cv2
    import numpy

    from scenedetect import ContentDetector, FrameTimecode, SceneManager, VideoCaptureAdapter

    # Callback to invoke on the first frame of every new scene detection.
    def on_new_scene(frame_img: numpy.ndarray, position: FrameTimecode):
        print(f"New scene found at frame {position.frame_num}.")

    # We open a file just for test purposes, but we can also use a device or pipe here.
    cap = cv2.VideoCapture(test_video_file)
    video = VideoCaptureAdapter(cap)
    # Now `video` can be used as normal with a `SceneManager`. If the input is non-terminating,
    # either set `end_time/duration` when calling `detect_scenes`, or call `scene_manager.stop()`.
    total_frames = 1000
    scene_manager = SceneManager()
    scene_manager.add_detector(ContentDetector())
    scene_manager.detect_scenes(video=video, duration=total_frames, callback=on_new_scene)


# TODO(v0.8): Remove this test when these deprecated modules are removed from the codebase.